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  • richardmitnick 2:58 pm on January 30, 2019 Permalink | Reply
    Tags: , , , BOSS Spectrograph - SDSS-III, , , Resolved spectroscopy (also called integral field spectroscopy), UCSC-UC Santa Cruz   

    From UC Santa Cruz: “MaNGA data release includes detailed maps of thousands of nearby galaxies” 

    UC Santa Cruz

    From UC Santa Cruz

    January 29, 2019
    Tim Stephens
    stephens@ucsc.edu

    Major data release from Sloan Digital Sky Survey includes galaxy maps, new data access and visualization tools, and a huge ‘stellar library’.

    1
    The MaNGA data set will eventually include more than 10,000 nearby galaxies, and the survey is already more than half way toward that goal. (Image credit: SDSS/MaNGA collaboration)

    The latest data release from the Sloan Digital Sky Survey (SDSS) includes observations revealing the internal structure and composition of nearly 5,000 nearby galaxies observed during the first three years of a program called Mapping Nearby Galaxies at Apache Point Observatory (MaNGA).

    SDSS 2.5 meter Telescope at Apache Point Observatory, near Sunspot NM, USA, Altitude 2,788 meters (9,147 ft)

    MaNGA uses a technique called resolved spectroscopy to study galaxies in much greater detail than previous surveys. Spectroscopy is a powerful tool for astronomers, yielding a wealth of information by measuring how much light an object emits at different wavelengths. In the past, astronomers typically acquired just one spectrum for each galaxy, but resolved spectroscopy (also called integral field spectroscopy) obtains hundreds of separate spectra covering every location within the galaxy.

    “Resolved spectroscopy allows us to dissect a galaxy and study its internal composition and the motions of its stars and gas,” explained MaNGA principal investigator Kevin Bundy, an associate researcher at UC Observatories and adjunct professor of astronomy and astrophysics at UC Santa Cruz.

    2
    The Marvin web site offers easy access to a wealth of information about each galaxy in the MaNGA survey, including maps of key features such as star formation, stellar motion, emission lines, and dozens of other properties important to astronomers. View larger image here. (Image credit: SDSS/MaNGA collaboration)

    3
    The MaNGA survey obtains spectra across the entire face of target galaxies using custom-designed fiber bundles. The bottom right illustrates how the array of fibers spatially samples a particular galaxy. The top right compares spectra observed by two fibers at different locations in the galaxy, showing how the spectrum of the central regions differs dramatically from outer regions. (Image Credit: Dana Berry/SkyWorks Digital Inc., David Law, and the SDSS collaboration)

    “People have been doing resolved spectroscopy for individual galaxies, but we’ve never had it for thousands of galaxies, so MaNGA gives us the statistical power to address a lot of important questions,” Bundy said.

    MaNGA’s goal is to understand the “life history” of present-day galaxies, from their initial birth and assembly, through their ongoing growth via star formation and mergers, to their death from “quenching” of star formation at late times. Bundy and his students at UC Santa Cruz, for example, have discovered evidence in the MaNGA data for outflows of hot ionized gas in “dead” galaxies, supporting the idea that powerful winds driven out from a galaxy’s central black hole can shut down star formation. Bundy’s team is also finding clues to how galaxies were assembled over time by studying the motions of their stars and gas and by analyzing the chemical signatures of stars in different parts of galaxies.

    One of three programs in the fourth phase of SDSS, MaNGA will eventually study a representative sample of some 10,000 nearby galaxies. Bundy said the survey is more than half way toward that goal and on track to reach it by 2020. Data from 4,621 galaxies are now publicly available as part of the 15th SDSS data release (the third data release for SDSS-IV).

    “This data release is a major milestone for us,” Bundy said. “MaNGA is already by far the largest survey of its kind, and this release includes both the data and the analytical tools the project has developed.”

    A powerful new interface called Marvin provides access to the MaNGA data and galaxy maps based on analyses of the data. Marvin includes a wide range of tools for searching, accessing, and visualizing the data. The Marvin web site offers easy access to a wealth of information about each galaxy, including maps of key features such as star formation, stellar motion, emission lines, and dozens of other properties important to astronomers. Kyle Westfall, a project scientist at UC Observatories, led the development of the data analysis pipeline that produced the maps and other data products now publicly available for the first time.

    Another important part of this data release is the MaNGA Stellar Library containing spectra of more than 3,000 stars in our Milky Way galaxy. When complete, it will include 5,000 to 6,000 stars. Researchers can use the spectra of these individual stars to try to reconstruct the spectrum of a galaxy and thereby figure out that galaxy’s unique mix of different star types.

    “The MaNGA Stellar Library is the largest library of stars ever compiled, with spectra from the same instruments used for the galaxies, so it’s a very powerful tool for understanding the nature of the stellar populations in these galaxies,” Bundy said.

    MaNGA Survey Scientist Renbin Yan of the University of Kentucky led the development of the Stellar Library.

    The MaNGA survey uses the two BOSS spectrographs at the 2.5-meter Sloan Foundation Telescope at Apache Point Observatory in New Mexico in a novel way.

    BOSS Spectrograph – SDSS-III

    Specially designed “integral field units,” each composed of tightly packed arrays of optical fibers, enable the measurement of spectra at multiple points in the same galaxy. The MaNGA spectra provide continuous coverage from optical to near-infrared wavelengths.

    Funding for the Sloan Digital Sky Survey IV has been provided by the Alfred P. Sloan Foundation, the U.S. Department of Energy Office of Science, and the Participating Institutions.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    UCSC Lick Observatory, Mt Hamilton, in San Jose, California, Altitude 1,283 m (4,209 ft)

    .

    UCO Lick Shane Telescope
    UCO Lick Shane Telescope interior
    Shane Telescope at UCO Lick Observatory, UCSC

    Lick Automated Planet Finder telescope, Mount Hamilton, CA, USA

    Lick Automated Planet Finder telescope, Mount Hamilton, CA, USA

    UC Santa Cruz campus
    The University of California, Santa Cruz, opened in 1965 and grew, one college at a time, to its current (2008-09) enrollment of more than 16,000 students. Undergraduates pursue more than 60 majors supervised by divisional deans of humanities, physical & biological sciences, social sciences, and arts. Graduate students work toward graduate certificates, master’s degrees, or doctoral degrees in more than 30 academic fields under the supervision of the divisional and graduate deans. The dean of the Jack Baskin School of Engineering oversees the campus’s undergraduate and graduate engineering programs.

    UCSC is the home base for the Lick Observatory.

    Lick Observatory's Great Lick 91-centimeter (36-inch) telescope housed in the South (large) Dome of main building
    Lick Observatory’s Great Lick 91-centimeter (36-inch) telescope housed in the South (large) Dome of main building

    Search for extraterrestrial intelligence expands at Lick Observatory
    New instrument scans the sky for pulses of infrared light
    March 23, 2015
    By Hilary Lebow
    1
    The NIROSETI instrument saw first light on the Nickel 1-meter Telescope at Lick Observatory on March 15, 2015. (Photo by Laurie Hatch) UCSC Lick Nickel telescope

    Astronomers are expanding the search for extraterrestrial intelligence into a new realm with detectors tuned to infrared light at UC’s Lick Observatory. A new instrument, called NIROSETI, will soon scour the sky for messages from other worlds.

    “Infrared light would be an excellent means of interstellar communication,” said Shelley Wright, an assistant professor of physics at UC San Diego who led the development of the new instrument while at the University of Toronto’s Dunlap Institute for Astronomy & Astrophysics.

    Wright worked on an earlier SETI project at Lick Observatory as a UC Santa Cruz undergraduate, when she built an optical instrument designed by UC Berkeley researchers. The infrared project takes advantage of new technology not available for that first optical search.

    Infrared light would be a good way for extraterrestrials to get our attention here on Earth, since pulses from a powerful infrared laser could outshine a star, if only for a billionth of a second. Interstellar gas and dust is almost transparent to near infrared, so these signals can be seen from great distances. It also takes less energy to send information using infrared signals than with visible light.

    Frank Drake, professor emeritus of astronomy and astrophysics at UC Santa Cruz and director emeritus of the SETI Institute, said there are several additional advantages to a search in the infrared realm.

    “The signals are so strong that we only need a small telescope to receive them. Smaller telescopes can offer more observational time, and that is good because we need to search many stars for a chance of success,” said Drake.

    The only downside is that extraterrestrials would need to be transmitting their signals in our direction, Drake said, though he sees this as a positive side to that limitation. “If we get a signal from someone who’s aiming for us, it could mean there’s altruism in the universe. I like that idea. If they want to be friendly, that’s who we will find.”

    Scientists have searched the skies for radio signals for more than 50 years and expanded their search into the optical realm more than a decade ago. The idea of searching in the infrared is not a new one, but instruments capable of capturing pulses of infrared light only recently became available.

    “We had to wait,” Wright said. “I spent eight years waiting and watching as new technology emerged.”

    Now that technology has caught up, the search will extend to stars thousands of light years away, rather than just hundreds. NIROSETI, or Near-Infrared Optical Search for Extraterrestrial Intelligence, could also uncover new information about the physical universe.

    “This is the first time Earthlings have looked at the universe at infrared wavelengths with nanosecond time scales,” said Dan Werthimer, UC Berkeley SETI Project Director. “The instrument could discover new astrophysical phenomena, or perhaps answer the question of whether we are alone.”

    NIROSETI will also gather more information than previous optical detectors by recording levels of light over time so that patterns can be analyzed for potential signs of other civilizations.

    “Searching for intelligent life in the universe is both thrilling and somewhat unorthodox,” said Claire Max, director of UC Observatories and professor of astronomy and astrophysics at UC Santa Cruz. “Lick Observatory has already been the site of several previous SETI searches, so this is a very exciting addition to the current research taking place.”

    NIROSETI will be fully operational by early summer and will scan the skies several times a week on the Nickel 1-meter telescope at Lick Observatory, located on Mt. Hamilton east of San Jose.

    The NIROSETI team also includes Geoffrey Marcy and Andrew Siemion from UC Berkeley; Patrick Dorval, a Dunlap undergraduate, and Elliot Meyer, a Dunlap graduate student; and Richard Treffers of Starman Systems. Funding for the project comes from the generous support of Bill and Susan Bloomfield.

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  • richardmitnick 2:53 pm on September 26, 2018 Permalink | Reply
    Tags: Alexie Leauthaud, , , , , First-year Subaru Hyper Suprime-Cam survey results yield cosmological constraints, , The deepest wide-field map of the three-dimensional distribution of matter in the universe, UCSC-UC Santa Cruz,   

    From UC Santa Cruz: Women in STEM- “First-year Subaru Hyper Suprime-Cam survey results yield cosmological constraints” Alexie Leauthaud 

    UC Santa Cruz

    From UC Santa Cruz

    September 25, 2018
    Tim Stephens
    stephens@ucsc.edu

    NAOJ Subaru Hyper Suprime-Cam

    NAOJ/Subaru Telescope at Mauna Kea Hawaii, USA,4,207 m (13,802 ft) above sea level

    Using the powerful Japanese Subaru telescope, the Hyper Suprime-Cam (HSC) survey collaboration team has made and analyzed the deepest wide-field map of the three-dimensional distribution of matter in the universe.

    The results place new constraints on the nature of the mysterious dark energy that is accelerating the expansion of the universe, said Alexie Leauthaud, assistant professor of astronomy and astrophysics at UC Santa Cruz and a member of the international collaboration.

    1
    Alexie Leauthaud (Photo by T. Stephens)

    The HSC survey, led by the astronomical communities of Japan and Taiwan and Princeton University, is an unprecedented effort to measure gravitational lensing, in which the gravity of a galaxy in the foreground of an image bends the light from a more distant galaxy as it passes by. Gravitational lensing can reveal dark matter, which accounts for about 80 percent of the mass in the universe but cannot be observed directly.

    Leauthaud has been involved in the survey from the beginning, joining the project when she was at the Kavli Institute for the Physics and Mathematics of the Universe (IPMU) at the University of Tokyo, before she joined the faculty at UC Santa Cruz. She helped to write the proposal that secured 300 nights for the survey on the Subaru telescope and has provided expertise with weak lensing measurements and performed critical data quality checks.

    2
    Left panel: The 3-dimensional dark matter map of the universe inferred from one of the six HSC observation areas is shown in the background with various shades of blue (brighter areas have more dark matter). The map was inferred from the distortions of shapes of galaxies in the HSC data which are indicated by white sticks. The stick lengths represent the amount of distortion and the angle of the stick corresponds to the direction of the distortion. Right panel: The measurements are enabled by the light from distant galaxies that travels through the Universe and gets deflected by matter at different epochs in the Universe, before reaching the Subaru telescope. (All images credit: C. Hikage et al.)

    Lumpiness

    3
    The cosmological constraints on the fractional contribution of matter to the energy budget of the universe (the rest of it corresponds to dark energy), and the clumpiness of the matter distribution today as inferred from the analysis of the 3d dark matter map. The results of the clumpiness of the matter distribution from HSC observations of the distant universe using weak gravitational lensing are consistent with results from other similar observations (Dark Energy Survey and the Kilo Degree Survey) of more nearby universe. The results from the cosmic microwave background observations during the universe’s infancy obtained by the Planck satellite are shown in blue.

    A team of scientists led by Chiaki Hikage at the Kavli IPMU has now used the gravitational distortion of images of about 10 million galaxies to make a precise measurement of the lumpiness of matter in the universe. By combining this measurement with observations of the cosmic microwave background by the European Space Agency’s Planck satellite and other cosmological experiments, the team has been able to further constrain dark energy.

    “Taken together in the context of other weak lensing data sets, the hints of a deviation from Planck are very intriguing,” Leauthaud said. “It is exciting to see what we have been able to achieve this early on in our survey. With our full data set, we will have the power to say whether or not there is a tension with Planck. That is incredibly exciting to me because we may be on the verge of learning something very interesting about the physics of dark energy.”

    Though quite weak, the gravitational lensing effect results in small but measurable distortions in the images of distant galaxies. Like a pointillist painting, the distorted images of millions of galaxies located further and further away paint a three-dimensional picture of the distribution of matter in the universe. The research team has characterized the precise amount of fluctuations in the matter distribution and their change over billions of years, from the universe’s adolescence to its adulthood.

    Precise measurements

    4
    Cosmological constraints on the dark energy equation of state: blue contours alone from HSC, red contours correspond to constraints after combining with cosmological results from the Planck CMB satellite and other contemporary cosmological measurements.

    The study required precise measurements of galaxy shapes. Since the weak lensing effect is quite small, the HSC team had to control various problems affecting the measurement of shapes, such as distortions due to the atmosphere and the instrument itself. The team overcame these difficulties by using detailed painstaking image simulations of the HSC survey based on Hubble Space Telescope images.

    When carrying out precise measurements of very small effects, it is known that people have a tendency to decide that their analysis is complete if their results confirm earlier results. The HSC team performed a so-called blind analysis of their data in order to avoid such “confirmation bias.” They carried out many tests of their catalogs for more than a year without ever seeing the actual values of cosmological parameters from their analysis or comparing with results from other experiments.

    The HSC weak lensing measurement is used to determine the lumpiness of matter in the universe, quantified by a parameter called S8. Larger S8, for example, would mean more structure such as galaxies in the universe. With the high-precision HSC data, the team determined S8 with a precision of 3.6 percent, which is similar to the precision with which it was measured by the weak lensing analysis from the Dark Energy Survey (DES). The DES surveyed​ ​14 times more area on the sky than HSC, but focused on the more nearby universe. With a deeper survey that images even fainter galaxies, the HSC team was able to map out a sharper dark matter distribution than was previously possible and achieved a similar precision measurement with a smaller area. This showcases the strength and complementarity of HSC among ongoing projects worldwide.

    Consistent picture

    When compared to the fluctuations expected from those seen in the universe’s infancy by the Planck satellite, the HSC measurements offer a consistent picture of the cosmological model. The universe today is dominated by dark matter and dark energy, and that dark energy behaves like Einstein’s cosmological constant—the simplest model.

    However, taken together the results from weak lensing surveys prefer a slightly smaller value of fluctuations than that predicted by the Planck satellite. This could just be a statistical fluctuation due to the limited amount of data, or it might be a signature of the breakdown of the standard model of the universe based on general relativity and the cosmological constant. The new HSC results come from a mere one tenth of the planned survey. When completed, the survey has the potential to deepen scientists’ understanding of the standard cosmological model by shedding light on the behavior of dark energy.

    The research paper has now been submitted to the journal ​Publications of the Astronomical Society of Japan​ and will undergo rigorous peer review by the scientific community.

    The HSC survey began in the spring of 2014 using the National Astronomical Observatory of Japan’s Subaru telescope located at the summit of Mt. Maunakea on the Big Island of Hawaii. The telescope features a large collecting area corresponding to a diameter of 8.2 meters, a wide angle camera that fits an area equal to about 9 moons in a single shot, and superb image quality, making it well suited to conduct a wide yet deep imaging survey of the sky. The survey has covered about 140 square degrees of sky (the area of 3,000 full moons) over 90 nights on the telescope​.

    The research will be uploaded to the preprint server arxiv.org and will be submitted to the Publication of the Astronomical Society of Japan.

    See the full article here.
    See the phsy.org article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    UCSC Lick Observatory, Mt Hamilton, in San Jose, California, Altitude 1,283 m (4,209 ft)

    .

    UCO Lick Shane Telescope
    UCO Lick Shane Telescope interior
    Shane Telescope at UCO Lick Observatory, UCSC

    Lick Automated Planet Finder telescope, Mount Hamilton, CA, USA

    Lick Automated Planet Finder telescope, Mount Hamilton, CA, USA

    UC Santa Cruz campus
    The University of California, Santa Cruz, opened in 1965 and grew, one college at a time, to its current (2008-09) enrollment of more than 16,000 students. Undergraduates pursue more than 60 majors supervised by divisional deans of humanities, physical & biological sciences, social sciences, and arts. Graduate students work toward graduate certificates, master’s degrees, or doctoral degrees in more than 30 academic fields under the supervision of the divisional and graduate deans. The dean of the Jack Baskin School of Engineering oversees the campus’s undergraduate and graduate engineering programs.

    UCSC is the home base for the Lick Observatory.

    Lick Observatory's Great Lick 91-centimeter (36-inch) telescope housed in the South (large) Dome of main building
    Lick Observatory’s Great Lick 91-centimeter (36-inch) telescope housed in the South (large) Dome of main building

    Search for extraterrestrial intelligence expands at Lick Observatory
    New instrument scans the sky for pulses of infrared light
    March 23, 2015
    By Hilary Lebow
    1
    The NIROSETI instrument saw first light on the Nickel 1-meter Telescope at Lick Observatory on March 15, 2015. (Photo by Laurie Hatch) UCSC Lick Nickel telescope

    Astronomers are expanding the search for extraterrestrial intelligence into a new realm with detectors tuned to infrared light at UC’s Lick Observatory. A new instrument, called NIROSETI, will soon scour the sky for messages from other worlds.

    “Infrared light would be an excellent means of interstellar communication,” said Shelley Wright, an assistant professor of physics at UC San Diego who led the development of the new instrument while at the University of Toronto’s Dunlap Institute for Astronomy & Astrophysics.

    Wright worked on an earlier SETI project at Lick Observatory as a UC Santa Cruz undergraduate, when she built an optical instrument designed by UC Berkeley researchers. The infrared project takes advantage of new technology not available for that first optical search.

    Infrared light would be a good way for extraterrestrials to get our attention here on Earth, since pulses from a powerful infrared laser could outshine a star, if only for a billionth of a second. Interstellar gas and dust is almost transparent to near infrared, so these signals can be seen from great distances. It also takes less energy to send information using infrared signals than with visible light.

    Frank Drake, professor emeritus of astronomy and astrophysics at UC Santa Cruz and director emeritus of the SETI Institute, said there are several additional advantages to a search in the infrared realm.

    “The signals are so strong that we only need a small telescope to receive them. Smaller telescopes can offer more observational time, and that is good because we need to search many stars for a chance of success,” said Drake.

    The only downside is that extraterrestrials would need to be transmitting their signals in our direction, Drake said, though he sees this as a positive side to that limitation. “If we get a signal from someone who’s aiming for us, it could mean there’s altruism in the universe. I like that idea. If they want to be friendly, that’s who we will find.”

    Scientists have searched the skies for radio signals for more than 50 years and expanded their search into the optical realm more than a decade ago. The idea of searching in the infrared is not a new one, but instruments capable of capturing pulses of infrared light only recently became available.

    “We had to wait,” Wright said. “I spent eight years waiting and watching as new technology emerged.”

    Now that technology has caught up, the search will extend to stars thousands of light years away, rather than just hundreds. NIROSETI, or Near-Infrared Optical Search for Extraterrestrial Intelligence, could also uncover new information about the physical universe.

    “This is the first time Earthlings have looked at the universe at infrared wavelengths with nanosecond time scales,” said Dan Werthimer, UC Berkeley SETI Project Director. “The instrument could discover new astrophysical phenomena, or perhaps answer the question of whether we are alone.”

    NIROSETI will also gather more information than previous optical detectors by recording levels of light over time so that patterns can be analyzed for potential signs of other civilizations.

    “Searching for intelligent life in the universe is both thrilling and somewhat unorthodox,” said Claire Max, director of UC Observatories and professor of astronomy and astrophysics at UC Santa Cruz. “Lick Observatory has already been the site of several previous SETI searches, so this is a very exciting addition to the current research taking place.”

    NIROSETI will be fully operational by early summer and will scan the skies several times a week on the Nickel 1-meter telescope at Lick Observatory, located on Mt. Hamilton east of San Jose.

    The NIROSETI team also includes Geoffrey Marcy and Andrew Siemion from UC Berkeley; Patrick Dorval, a Dunlap undergraduate, and Elliot Meyer, a Dunlap graduate student; and Richard Treffers of Starman Systems. Funding for the project comes from the generous support of Bill and Susan Bloomfield.

     
  • richardmitnick 3:06 pm on September 14, 2018 Permalink | Reply
    Tags: , , , Quantum information science on the verge of a technological revolution, , UCSC-UC Santa Cruz   

    From UC Santa Cruz: “Quantum information science on the verge of a technological revolution” Revised 

    UC Santa Cruz

    From UC Santa Cruz

    September 13, 2018
    Tim Stephens
    stephens@ucsc.edu

    Theorist Yuan Ping is developing computational methods to guide the design of new materials for quantum computing and other quantum information technologies.

    1
    Materials scientist Yuan Ping (center) with graduate student Tyler Smart (left) and postdoctoral fellow Feng Wu (right) at the UCSC supercomputer center. (Photo by C. Lagattuta)

    See https://sciencesprings.wordpress.com/2018/09/10/from-uc-santa-cruz-nsf-funds-powerful-new-supercomputer-for-uc-santa-cruz-researchers/

    3
    Researchers are racing to develop quantum information technologies, in which information will be stored in quantum bits, or qubits. Qubits can be made from any quantum system that has two states, such as the spin states of electrons. (Image credit: National Science Foundation)

    Quantum computers may one day solve problems that are effectively beyond the capacity of conventional supercomputers. Quantum communications may enable instantaneous, secure transmission of information across vast distances, and quantum sensors may provide previously unheard of sensitivities.

    A global race is on to develop these new quantum information technologies, in which information will be stored in quantum bits, or qubits. In conventional digital technologies, a bit is either 0 or 1, whereas a qubit can represent both states at the same time because of a strange phenomenon of quantum physics called superposition. In theory, this will enable a massive increase in computing speed and capacity for certain types of calculations.

    At UC Santa Cruz, materials scientists are working to develop novel materials that can serve as the foundation for quantum information technology, just as silicon chips paved the way for today’s digital technologies. Several different systems for creating and manipulating qubits have been proposed and implemented, but for now they remain too cumbersome for real-world applications.

    “Our focus as materials scientists is on what material we should use as the fundamental element to carry the information. Other researchers are more concerned with how to wire it up to make a device that can perform calculations, but we’re focused on the material basis of the qubit,” said Yuan Ping, assistant professor of chemistry and biochemistry at UC Santa Cruz.

    2D materials

    In particular, Ping and other UCSC researchers are focusing on defects in extremely thin materials, called two-dimensional (2D) materials. Defects or imperfections in the atomic structure of a material can function as qubits because information can be encoded in the spin states of their electrons. This phenomenon has been well studied in other types of materials, most notably the “nitrogen vacancy” or NV defect in diamond. But according to Ping, 2D materials offer significant advantages.

    “Unlike diamond, 2D materials are relatively cheap and easy to make, they are scalable, and they are easy to integrate into a solid-state device,” she said. “They are also stable at room temperature, which is important because a lot of the qubit systems implemented so far use superconductors that can only operate at very low temperatures.”

    There are a lot of different 2D materials, however, and a lot of ways to put defects into them. The possibilities are almost endless, and it’s not practical to synthesize and test them all experimentally to see which have the best properties for quantum technologies.

    That’s where theorists like Ping come in. She is developing computational methods that can be used to predict the properties of defects in 2D materials reliably and efficiently. In December 2017, her team published a paper in Physical Review Materials establishing the fundamental principles for doing calculations to accurately describe charge defects, electronic states, and spin dynamics in 2D materials. (Her coauthors on the paper include postdoctoral fellow Feng Wu, graduate student Andrew Galatas, and collaborators Dario Rocca at University of Lorraine in France and Ravishankar Sundararaman at Rensselaer Polytechnic Institute.)

    In July, Ping won a $350,000 grant from the National Science Foundation to further develop these computational methods.

    “We’re developing a reliable set of tools to predict the electronic structure, excited-state lifetime, and quantum-state coherence time of defects in 2D materials at a quantum mechanical level,” Ping said. “We do calculations from first principles, meaning we don’t need any input from experiments. Everything is predicted based on quantum mechanics.”

    Quantum weirdness

    The world of quantum mechanics is notoriously counter-intuitive and hard to grasp. Concepts such as superposition and entanglement defy common sense, yet they have been demonstrated conclusively and are fundamental to quantum information technologies. Superposition, when a particle exists in two different states simultaneously, is often compared to a spinning coin, neither heads nor tails until it stops spinning. Entanglement creates a link between the quantum states of two particles or qubits, so it is as if the outcome of one spinning coin determined the outcome of another spinning coin.

    A major challenge in exploiting these phenomena for quantum information technologies is their inherent fragility. Interaction with the environment causes a superposition to fall into one state or the other. Called decoherence, this can be caused by vibrations of the atoms in the material and other subtle effects.

    “You want qubits to be well insulated from the environment to give longer coherence times,” Ping said.

    One 2D material that has shown promise for quantum technologies is ultrathin hexagonal boron nitride. Ping used her computational methods to investigate various defects in this material and identified a promising candidate for scalable quantum applications. This defect (a nitrogen vacancy adjacent to carbon substitution of boron) is predicted to have stable spin states well insulated from the environment and bright optical transitions, making it a good source for single photon emission and a good candidate for qubits.

    “Quantum emitters, which can emit one photon at a time, are important for optically-based quantum information processing, information security, and ultrasensitive sensing,” Ping said.

    She works closely with experimentalists, helping to interpret their results and guide their efforts to create novel materials with desirable properties for quantum technologies. Her group is part of a large collaborative effort, the Quantum Information Science and Engineering Network (QISE-NET), funded by the National Science Foundation. Tyler Smart, a graduate student in Ping’s group, is funded by QISE-NET and is working on a project at Argonne National Laboratory.

    “He will be traveling to Chicago to present his research every few months,” Ping said. “There are about 20 universities as well as national laboratories and industry partners in the network, meeting regularly and sharing ideas, which is important because it’s a fast-moving field.”

    One of the National Science Foundation’s 10 Big Ideas for Future NSF Investments is “The Quantum Leap: Leading the Next Quantum Revolution.”

    The Department of Energy is also investing in this area, as are companies such as Google and Intel, hoping to exploit quantum mechanics to develop next-generation technologies for computing, sensing, and communications.

    “They are all investing in it because it will take a lot of effort to develop this field, and the potential is so great,” Ping said.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    UCO Lick Shane Telescope
    UCO Lick Shane Telescope interior
    Shane Telescope at UCO Lick Observatory, UCSC

    Lick Automated Planet Finder telescope, Mount Hamilton, CA, USA

    Lick Automated Planet Finder telescope, Mount Hamilton, CA, USA

    UC Santa Cruz campus
    The University of California, Santa Cruz, opened in 1965 and grew, one college at a time, to its current (2008-09) enrollment of more than 16,000 students. Undergraduates pursue more than 60 majors supervised by divisional deans of humanities, physical & biological sciences, social sciences, and arts. Graduate students work toward graduate certificates, master’s degrees, or doctoral degrees in more than 30 academic fields under the supervision of the divisional and graduate deans. The dean of the Jack Baskin School of Engineering oversees the campus’s undergraduate and graduate engineering programs.

    UCSC is the home base for the Lick Observatory.

    Lick Observatory's Great Lick 91-centimeter (36-inch) telescope housed in the South (large) Dome of main building
    Lick Observatory’s Great Lick 91-centimeter (36-inch) telescope housed in the South (large) Dome of main building

    Search for extraterrestrial intelligence expands at Lick Observatory
    New instrument scans the sky for pulses of infrared light
    March 23, 2015
    By Hilary Lebow
    1
    The NIROSETI instrument saw first light on the Nickel 1-meter Telescope at Lick Observatory on March 15, 2015. (Photo by Laurie Hatch) UCSC Lick Nickel telescope

    Astronomers are expanding the search for extraterrestrial intelligence into a new realm with detectors tuned to infrared light at UC’s Lick Observatory. A new instrument, called NIROSETI, will soon scour the sky for messages from other worlds.

    “Infrared light would be an excellent means of interstellar communication,” said Shelley Wright, an assistant professor of physics at UC San Diego who led the development of the new instrument while at the University of Toronto’s Dunlap Institute for Astronomy & Astrophysics.

    Wright worked on an earlier SETI project at Lick Observatory as a UC Santa Cruz undergraduate, when she built an optical instrument designed by UC Berkeley researchers. The infrared project takes advantage of new technology not available for that first optical search.

    Infrared light would be a good way for extraterrestrials to get our attention here on Earth, since pulses from a powerful infrared laser could outshine a star, if only for a billionth of a second. Interstellar gas and dust is almost transparent to near infrared, so these signals can be seen from great distances. It also takes less energy to send information using infrared signals than with visible light.

    Frank Drake, professor emeritus of astronomy and astrophysics at UC Santa Cruz and director emeritus of the SETI Institute, said there are several additional advantages to a search in the infrared realm.

    “The signals are so strong that we only need a small telescope to receive them. Smaller telescopes can offer more observational time, and that is good because we need to search many stars for a chance of success,” said Drake.

    The only downside is that extraterrestrials would need to be transmitting their signals in our direction, Drake said, though he sees this as a positive side to that limitation. “If we get a signal from someone who’s aiming for us, it could mean there’s altruism in the universe. I like that idea. If they want to be friendly, that’s who we will find.”

    Scientists have searched the skies for radio signals for more than 50 years and expanded their search into the optical realm more than a decade ago. The idea of searching in the infrared is not a new one, but instruments capable of capturing pulses of infrared light only recently became available.

    “We had to wait,” Wright said. “I spent eight years waiting and watching as new technology emerged.”

    Now that technology has caught up, the search will extend to stars thousands of light years away, rather than just hundreds. NIROSETI, or Near-Infrared Optical Search for Extraterrestrial Intelligence, could also uncover new information about the physical universe.

    “This is the first time Earthlings have looked at the universe at infrared wavelengths with nanosecond time scales,” said Dan Werthimer, UC Berkeley SETI Project Director. “The instrument could discover new astrophysical phenomena, or perhaps answer the question of whether we are alone.”

    NIROSETI will also gather more information than previous optical detectors by recording levels of light over time so that patterns can be analyzed for potential signs of other civilizations.

    “Searching for intelligent life in the universe is both thrilling and somewhat unorthodox,” said Claire Max, director of UC Observatories and professor of astronomy and astrophysics at UC Santa Cruz. “Lick Observatory has already been the site of several previous SETI searches, so this is a very exciting addition to the current research taking place.”

    NIROSETI will be fully operational by early summer and will scan the skies several times a week on the Nickel 1-meter telescope at Lick Observatory, located on Mt. Hamilton east of San Jose.

    The NIROSETI team also includes Geoffrey Marcy and Andrew Siemion from UC Berkeley; Patrick Dorval, a Dunlap undergraduate, and Elliot Meyer, a Dunlap graduate student; and Richard Treffers of Starman Systems. Funding for the project comes from the generous support of Bill and Susan Bloomfield.

     
  • richardmitnick 12:33 pm on July 26, 2018 Permalink | Reply
    Tags: , , , , , Galactic-wind whisperers, OLCF ORNL Cray Titan XK7 Supercomputer, , UCSC-UC Santa Cruz   

    From ASCRDiscovery: “Galactic-wind whisperers” 

    From ASCRDiscovery
    ASCR – Advancing Science Through Computing

    UC Santa Cruz and Princeton University team simulates galactic winds on the DOE’s Titan supercomputer.

    ORNL Cray Titan XK7 Supercomputer

    1
    A high-resolution, 18-billion-cell simulation of galactic winds created by Cholla hydrodynamic code run on DOE’s Titan supercomputer at the Oak Ridge Leadership Computing Facility, an Office of Science user facility. Shown is a calculation of a disk-shaped galaxy (green) where supernova explosions near the center of the galaxy have driven outflowing galactic winds (red, pink, purple). The red to purple transition indicates areas of increasing wind velocity. Image courtesy of Schneider, Robertson and Thompson via arXiv:1803.01005.

    Winds made of gas particles swirl around galaxies at hundreds of kilometers per second. Astronomers suspect the gusts are stirred by nearby exploding stars that exude photons powerful enough to move the gas. Whipped fast enough, this wind can be ejected into intergalactic space.

    Astronomers have known for decades that these colossal gales exist, but they’re still parsing precisely what triggers and drives them. “Galactic winds set the properties of certain components of galaxies like the stars and the gas,” says Brant Robertson, an associate professor of astronomy and astrophysics at the University of California, Santa Cruz (UCSC). “Being able to model galactic winds has implications ranging from understanding how and why galaxies form to measuring things like dark energy and the acceleration of the universe.”

    But getting there has been extraordinarily difficult. Models must simultaneously resolve hydrodynamics, radiative cooling and other physics on the scale of a few parsecs in and around a galactic disk. Because the winds consist of hot and cold components pouring out at high velocities, capturing all the relevant processes with a reasonable spatial resolution requires tens of billions of computational cells that tile the disk’s entire volume.

    Most traditional models would perform the bulk of calculations using a computer’s central processing unit, with bits and pieces farmed out to its graphics processing units (GPUs). Robertson had a hunch, though, that thousands of GPUs operating in parallel could do the heavy lifting – a feat that hadn’t been tried for large-scale astronomy projects. Robertson’s experience running numerical simulations on supercomputers as a Harvard University graduate student helped him overcome challenges associated with getting the GPUs to efficiently communicate with each other.

    Once he’d decided on the GPU-based architecture, Robertson enlisted Evan Schneider, then a graduate student in his University of Arizona lab and now a Hubble Fellow at Princeton University, to work with him on a hydrodynamic code that suited the computational approach. They dubbed it Computational Hydrodynamics on II Architectures, or Cholla – also a cactus indigenous to the Southwest, and the two lowercase Ls represent those in the middle of the word “parallel.”

    “We knew that if we could design an effective GPU-centric code,” Schneider says, “we could really do something completely new and exciting.”

    With Cholla in hand, she and Robertson searched for a computer powerful enough to get the most out of it. They turned to Titan, a Cray XK7 supercomputer housed at the Oak Ridge Leadership Computing Facility (OLCF), a Department of Energy (DOE) Office of Science user facility at DOE’s Oak Ridge National Laboratory.

    Robertson notes that “simulating galactic winds requires exquisite resolution over a large volume to fully understand the system, much better resolution than other cosmological simulations used to model populations of galaxies. You really need a machine like Titan for this kind of project.”

    Cholla had found its match in Titan, a 27-petaflops system containing more than 18,000 GPUs. After testing the code on a smaller GPU cluster at the University of Arizona, Robertson and Schneider benchmarked it on Titan with the support of two small OLCF director’s discretionary awards. “We were definitely hoping that Titan would be the main workhorse for what we were doing,” Schneider says.

    Robertson and Schneider then unleashed Cholla to test a well-known theory for how galactic winds work. They simulated a hot, supernova-driven wind colliding with a cool gas cloud across 300 light years. With Cholla’s remarkable resolution, they zoomed in on various simulated regions to study phases and properties of galactic wind in isolation, letting the team rule out a theory that cold clouds close to the galaxy’s center could be pushed out by hot, fast-moving supernova wind. It turns out the hot wind shreds the cold clouds, turning them into ribbons that would be difficult to push on.

    With time on Titan allocated through DOE’s INCITE program (for Innovative and Novel Computational Impact on Theory and Experiment), Robertson and Schneider recently used Cholla to generate a simulation using nearly a trillion cells to model an entire galaxy spanning more than 30,000 light years – 10 to 20 times bigger than the largest galactic simulation produced so far. Robertson and Schneider expect the calculations will help test another potential explanation for how galactic winds work. They also may reveal additional details about these phenomena and the forces that regulate galaxies that are important for understanding low-mass varieties, dark matter and the universe’s evolution.

    Robertson and Schneider hope that additional DOE machines – including Summit, a 200-petaflops behemoth that ranks as the world’s fastest supercomputer – will soon support Cholla, which is now publicly available on GitHub.

    ORNL IBM AC922 SUMMIT supercomputer. Credit: Carlos Jones, Oak Ridge National Laboratory/U.S. Dept. of Energy

    To support the code’s dissemination, last year Schneider gave a brief how-to session at Los Alamos National Laboratory. More recently, she and Robertson ran a similar session at OLCF. “There are many applications and developments that could be added to Cholla that would be useful for people who are interested in any type of computational fluid dynamics, not just astrophysics,” Robertson says.

    Robertson also is exploring using GPUs for deep-learning approaches to astrophysics. His lab has been working to adapt a deep-learning model that biologists use to identify cancerous cells. Robertson thinks this method can automate galaxy identification, a crucial need for projects like the LSST, or Large Synoptic Survey Telescope.

    LSST


    LSST Camera, built at SLAC



    LSST telescope, currently under construction on the El Peñón peak at Cerro Pachón Chile, a 2,682-meter-high mountain in Coquimbo Region, in northern Chile, alongside the existing Gemini South and Southern Astrophysical Research Telescopes.

    Its DOE-funded camera “will take an image of the whole southern sky every three days. There’s a huge amount of information,” says Robertson, who’s also co-chair of the LSST Galaxies Science Collaboration. “LSST is expected to find on the order of 30 billion galaxies, and it’s impossible to think that humans can look at all those and figure out what they are.”

    Normally, calculations have to be quite intensive to get substantial time on Titan, and Robertson believes the deep-learning project may not pass the bar. “However, because DOE has been supporting GPU-enabled systems, there is the possibility that, in a few years when the LSST data comes in, there may be an appropriate DOE system that could help with the analyses.”

    See the full article here.


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    Please help promote STEM in your local schools.

    Stem Education Coalition

    ASCRDiscovery is a publication of The U.S. Department of Energy

     
  • richardmitnick 5:23 pm on June 14, 2018 Permalink | Reply
    Tags: , , , , One black hole or two? Dust clouds can explain puzzling features of active galactic nuclei, , UCSC-UC Santa Cruz   

    From UCSC via Royal Astronomical Society: “One black hole or two? Dust clouds can explain puzzling features of active galactic nuclei” 

    UC Santa Cruz

    From UC Santa Cruz

    Royal Astronomical Society
    14 June 2018

    Tim Stephens
    University of California, Santa Cruz (UCSC)
    United States
    Tel: +1 (831) 459 4352
    stephens@ucsc.edu

    Dr Robert Massey
    Royal Astronomical Society
    Tel: +44 (0)20 7292 3979
    Mob: +44 (0)7802 877 699
    rmassey@ras.ac.uk

    Dr Morgan Hollis
    Royal Astronomical Society
    Tel: +44 (0)20 7292 3977
    Mob: +44 (0)7802 877 700
    mhollis@ras.ac.uk

    Science contact

    Dr Martin Gaskell
    University of California, Santa Cruz
    mgaskell@ucsc.edu

    Researchers at the University of California, Santa Cruz (UCSC), believe clouds of dust, rather than twin black holes, can explain the features found in active galactic nuclei (AGNs). The team publish their results today (14 June) in a paper in Monthly Notices of the Royal Astronomical Society.

    1
    An artist’s impression of what an active galactic nucleus might look like at close quarters. The accretion disk produces the brilliant light in the centre. The broad-line region is just above the accretion disk and lost in the glare. Dust clouds are being driven upwards by the intense radiation. Credit: Peter Z. Harrington.

    Many large galaxies have an AGN, a small bright central region powered by matter spiralling into a supermassive black hole. When these black holes are vigorously swallowing matter, they are surrounded by hot, rapidly-moving gas known as the “broad-line region” (so-called because the spectral lines from this region are broadened by the rapid motion of the gas).

    The emission from this gas is one of the best sources of information about the mass of the central black hole and how it is growing. The nature of this gas is however poorly understood; in particular there is less emission than expected from gas moving at certain velocities. The breakdown of simple models has led some astrophysicists to think that many AGNs might have not one but two black holes in them.

    The new analysis is led by Martin Gaskell, a research associate in astronomy and astrophysics at UCSC. Rather than invoking two black holes, it explains much of the apparent complexity and variability of the emissions from the broad-line region as the results of small clouds of dust that can partially obscure the innermost regions of AGNs.

    Gaskell comments: “We’ve shown that a lot of mysterious properties of active galactic nuclei can be explained by these small dusty clouds causing changes in what we see.”

    Co-author Peter Harrington, a UCSC graduate student who began work on the project as an undergraduate, explained that gas spiralling towards a galaxy’s central black hole forms a flat “accretion disk”, and the superheated gas in the accretion disk emits intense thermal radiation. Some of that light is “reprocessed” (absorbed and re-emitted) by hydrogen and other gases swirling above the accretion disk in the broad-line region. Above and beyond this is a region of dust.

    “Once the dust crosses a certain threshold it is subjected to the strong radiation from the accretion disk”, said Harrington. The authors believe this radiation is so intense that it blows the dust away from the disk, resulting in a clumpy outflow of dust clouds starting at the outer edge of the broad-line region.

    The effect of the dust clouds on the light emitted is to make the light coming from behind them look fainter and redder, just as the earth’s atmosphere makes the sun look fainter and redder at sunset. Gaskell and Harrington developed a computer code to model the effects of these dust clouds on observations of the broad-line region.

    The two scientists also show that by including dust clouds in their model, it can replicate many features of emission from the broad-line region that have long puzzled astrophysicists. Rather than the gas having a changing, asymmetrical distribution that is hard to explain, the gas is simply in a uniform, symmetric, turbulent disk around the black hole. The apparent asymmetries and changes are due to dust clouds passing in front of the broad-line region and making the regions behind them look fainter and redder.

    “We think it is a much more natural explanation of the asymmetries and changes than other more exotic theories, such as binary black holes, that have been invoked to explain them,” Gaskell said. “Our explanation lets us retain the simplicity of the standard AGN model of matter spiralling onto a single black hole.”

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    UCO Lick Shane Telescope
    UCO Lick Shane Telescope interior
    Shane Telescope at UCO Lick Observatory, UCSC

    Lick Automated Planet Finder telescope, Mount Hamilton, CA, USA

    Lick Automated Planet Finder telescope, Mount Hamilton, CA, USA

    UC Santa Cruz campus
    The University of California, Santa Cruz, opened in 1965 and grew, one college at a time, to its current (2008-09) enrollment of more than 16,000 students. Undergraduates pursue more than 60 majors supervised by divisional deans of humanities, physical & biological sciences, social sciences, and arts. Graduate students work toward graduate certificates, master’s degrees, or doctoral degrees in more than 30 academic fields under the supervision of the divisional and graduate deans. The dean of the Jack Baskin School of Engineering oversees the campus’s undergraduate and graduate engineering programs.

    UCSC is the home base for the Lick Observatory.

    Lick Observatory's Great Lick 91-centimeter (36-inch) telescope housed in the South (large) Dome of main building
    Lick Observatory’s Great Lick 91-centimeter (36-inch) telescope housed in the South (large) Dome of main building

    Search for extraterrestrial intelligence expands at Lick Observatory
    New instrument scans the sky for pulses of infrared light
    March 23, 2015
    By Hilary Lebow
    1
    The NIROSETI instrument saw first light on the Nickel 1-meter Telescope at Lick Observatory on March 15, 2015. (Photo by Laurie Hatch) UCSC Lick Nickel telescope

    Astronomers are expanding the search for extraterrestrial intelligence into a new realm with detectors tuned to infrared light at UC’s Lick Observatory. A new instrument, called NIROSETI, will soon scour the sky for messages from other worlds.

    “Infrared light would be an excellent means of interstellar communication,” said Shelley Wright, an assistant professor of physics at UC San Diego who led the development of the new instrument while at the University of Toronto’s Dunlap Institute for Astronomy & Astrophysics.

    Wright worked on an earlier SETI project at Lick Observatory as a UC Santa Cruz undergraduate, when she built an optical instrument designed by UC Berkeley researchers. The infrared project takes advantage of new technology not available for that first optical search.

    Infrared light would be a good way for extraterrestrials to get our attention here on Earth, since pulses from a powerful infrared laser could outshine a star, if only for a billionth of a second. Interstellar gas and dust is almost transparent to near infrared, so these signals can be seen from great distances. It also takes less energy to send information using infrared signals than with visible light.

    Frank Drake, professor emeritus of astronomy and astrophysics at UC Santa Cruz and director emeritus of the SETI Institute, said there are several additional advantages to a search in the infrared realm.

    “The signals are so strong that we only need a small telescope to receive them. Smaller telescopes can offer more observational time, and that is good because we need to search many stars for a chance of success,” said Drake.

    The only downside is that extraterrestrials would need to be transmitting their signals in our direction, Drake said, though he sees this as a positive side to that limitation. “If we get a signal from someone who’s aiming for us, it could mean there’s altruism in the universe. I like that idea. If they want to be friendly, that’s who we will find.”

    Scientists have searched the skies for radio signals for more than 50 years and expanded their search into the optical realm more than a decade ago. The idea of searching in the infrared is not a new one, but instruments capable of capturing pulses of infrared light only recently became available.

    “We had to wait,” Wright said. “I spent eight years waiting and watching as new technology emerged.”

    Now that technology has caught up, the search will extend to stars thousands of light years away, rather than just hundreds. NIROSETI, or Near-Infrared Optical Search for Extraterrestrial Intelligence, could also uncover new information about the physical universe.

    “This is the first time Earthlings have looked at the universe at infrared wavelengths with nanosecond time scales,” said Dan Werthimer, UC Berkeley SETI Project Director. “The instrument could discover new astrophysical phenomena, or perhaps answer the question of whether we are alone.”

    NIROSETI will also gather more information than previous optical detectors by recording levels of light over time so that patterns can be analyzed for potential signs of other civilizations.

    “Searching for intelligent life in the universe is both thrilling and somewhat unorthodox,” said Claire Max, director of UC Observatories and professor of astronomy and astrophysics at UC Santa Cruz. “Lick Observatory has already been the site of several previous SETI searches, so this is a very exciting addition to the current research taking place.”

    NIROSETI will be fully operational by early summer and will scan the skies several times a week on the Nickel 1-meter telescope at Lick Observatory, located on Mt. Hamilton east of San Jose.

    The NIROSETI team also includes Geoffrey Marcy and Andrew Siemion from UC Berkeley; Patrick Dorval, a Dunlap undergraduate, and Elliot Meyer, a Dunlap graduate student; and Richard Treffers of Starman Systems. Funding for the project comes from the generous support of Bill and Susan Bloomfield.

     
  • richardmitnick 7:38 am on May 23, 2018 Permalink | Reply
    Tags: Downward positron beam from a terrestrial gamma-ray flash, , Hurricane Hunter aircraft NOAA, Lightning in the eyewall of a hurricane beamed antimatter toward the ground, UCSC SCIPP labs ADELE-Airborne Detector for Energetic Lightning Emissions, UCSC-UC Santa Cruz   

    From UC Santa Cruz: “Lightning in the eyewall of a hurricane beamed antimatter toward the ground” 

    UC Santa Cruz

    From UC Santa Cruz

    May 21, 2018
    Tim Stephens
    stephens@ucsc.edu

    First detection of the downward positron beam from a terrestrial gamma-ray flash was captured by an instrument flown through the eyewall of Hurricane Patricia in 2015.

    1
    Hurricane Patricia was the most intense tropical cyclone ever recorded in the Western Hemisphere as it approached the west coast of Mexico in 2015. (NASA image by Jeff Schmaltz, LANCE/EOSDIS Rapid Response)

    Hurricane Patricia, which battered the west coast of Mexico in 2015, was the most intense tropical cyclone ever recorded in the Western Hemisphere. Amid the extreme violence of the storm, scientists observed something new: a downward beam of positrons, the antimatter counterpart of electrons, creating a burst of powerful gamma-rays and x-rays.

    Detected by an instrument aboard NOAA’s Hurricane Hunter aircraft, which flew through the eyewall of the storm at its peak intensity, the positron beam was not a surprise to the UC Santa Cruz scientists who built the instrument. But it was the first time anyone has observed this phenomenon.

    Hurricane Hunter aircraft. Credit NOAA

    According to David Smith, a professor of physics at UC Santa Cruz, the positron beam was the downward component of an upward terrestrial gamma-ray flash that sent a short blast of radiation into space above the storm. Terrestrial gamma-ray flashes (TGFs) were first seen in 1994 by space-based gamma-ray detectors. They occur in conjunction with lightning and have now been observed thousands of times by orbiting satellites. A reverse positron beam was predicted by theoretical models of TGFs, but had never been detected.

    UCSC SCIPP labs ADELE-Airborne Detector for Energetic Lightning Emissions

    “This is the first confirmation of that theoretical prediction, and it shows that TGFs are piercing the atmosphere from top to bottom with high-energy radiation,” Smith said. “This event could have been detected from space, like almost all the other reported TGFs, as an upward beam caused by an avalanche of electrons. We saw it from below because of a beam of antimatter (positrons) sent in the opposite direction.”

    One unexpected implication of the study, published May 17 in the Journal of Geophysical Research: Atmospheres, is that many TGFs could be detected via the reverse positron beam using ground-based instruments at high altitudes. It’s not necessary to fly into the eye of a hurricane.

    “We detected it at an altitude of 2.5 kilometers, and I estimated our detectors could have seen it down to 1.5 kilometers. That’s the altitude of Denver, so there are a lot of places where you could in theory see them if you had an instrument in the right place at the right time during a thunderstorm,” Smith said.

    Unresolved questions

    Despite the confirmation of the reverse positron beam, many questions remain unresolved about the mechanisms that drive TGFs. Strong electric fields in thunderstorms can accelerate electrons to near the speed of light, and these “relativistic” electrons emit gamma-rays when they scatter off of atoms in the atmosphere. The electrons can also knock other electrons off of atoms and accelerate them to high energies, creating an avalanche of relativistic electrons. A TGF, which is an extremely bright flash of gamma-rays, requires a large number of avalanches of relativistic electrons.

    “It’s an extraordinary event, and we still don’t understand how it gets so bright,” Smith said.

    The source of the positrons, however, is a well known phenomenon in physics called pair production, in which a gamma ray interacts with the nucleus of an atom to create an electron and a positron. Since they have opposite charges, they are accelerated in opposite directions by the electric field of the thunderstorm. The downward moving positrons produce x-rays and gamma-rays in their direction of travel when they collide with atomic nuclei, just like the upward moving electrons.

    “What we saw in the aircraft are the gamma-rays produced by the downward positron beam,” Smith said.

    First author Gregory Bowers, now at Los Alamos National Laboratory, and coauthor Nicole Kelley, now at Swift Navigation, were both graduate students at UC Santa Cruz when they worked together on the instrument that made the detection. The Airborne Detector for Energetic Lightning Emissions (ADELE) mark II was designed to observe TGFs up close by measuring x-rays and gamma-rays from aircraft flown into or above thunderstorms.

    Getting too close to a TGF could be hazardous, although the risk drops off rapidly with distance from the source. The gamma-ray dose at a distance of one kilometer would be negligible, Smith said. “It’s hypothetically a risk, but the odds are quite small,” he said. “I don’t ask pilots to fly into thunderstorms, but if they’re going anyway I’ll put an instrument on board.”

    Smith’s group was the first to detect a TGF from an airplane using an earlier instrument, the ADELE mark I. In that case, the upward beam from the TGF was detected above a thunderstorm. For this study, the ADELE mark II flew aboard NOAA’s Hurricane Hunter WP-3D Orion during the Atlantic hurricane season.

    In addition to Bowers, Smith, and Kelley, the coauthors of the paper include Forest Martinez-McKinney at UC Santa Cruz, Joseph Dwyer at the University of New Hampshire, and scientists at Duke University, Earth Networks, University of Washington, NOAA, and Florida Institute of Technology. This work was funded by the National Science Foundation.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.
    stem
    Stem Education Coalition

    UCO Lick Shane Telescope
    UCO Lick Shane Telescope interior
    Shane Telescope at UCO Lick Observatory, UCSC

    Lick Automated Planet Finder telescope, Mount Hamilton, CA, USA

    Lick Automated Planet Finder telescope, Mount Hamilton, CA, USA

    UC Santa Cruz campus
    The University of California, Santa Cruz, opened in 1965 and grew, one college at a time, to its current (2008-09) enrollment of more than 16,000 students. Undergraduates pursue more than 60 majors supervised by divisional deans of humanities, physical & biological sciences, social sciences, and arts. Graduate students work toward graduate certificates, master’s degrees, or doctoral degrees in more than 30 academic fields under the supervision of the divisional and graduate deans. The dean of the Jack Baskin School of Engineering oversees the campus’s undergraduate and graduate engineering programs.

    UCSC is the home base for the Lick Observatory.

    Lick Observatory's Great Lick 91-centimeter (36-inch) telescope housed in the South (large) Dome of main building
    Lick Observatory’s Great Lick 91-centimeter (36-inch) telescope housed in the South (large) Dome of main building

    Search for extraterrestrial intelligence expands at Lick Observatory
    New instrument scans the sky for pulses of infrared light
    March 23, 2015
    By Hilary Lebow
    1
    The NIROSETI instrument saw first light on the Nickel 1-meter Telescope at Lick Observatory on March 15, 2015. (Photo by Laurie Hatch) UCSC Lick Nickel telescope

    Astronomers are expanding the search for extraterrestrial intelligence into a new realm with detectors tuned to infrared light at UC’s Lick Observatory. A new instrument, called NIROSETI, will soon scour the sky for messages from other worlds.

    “Infrared light would be an excellent means of interstellar communication,” said Shelley Wright, an assistant professor of physics at UC San Diego who led the development of the new instrument while at the University of Toronto’s Dunlap Institute for Astronomy & Astrophysics.

    Wright worked on an earlier SETI project at Lick Observatory as a UC Santa Cruz undergraduate, when she built an optical instrument designed by UC Berkeley researchers. The infrared project takes advantage of new technology not available for that first optical search.

    Infrared light would be a good way for extraterrestrials to get our attention here on Earth, since pulses from a powerful infrared laser could outshine a star, if only for a billionth of a second. Interstellar gas and dust is almost transparent to near infrared, so these signals can be seen from great distances. It also takes less energy to send information using infrared signals than with visible light.

    5
    UCSC alumna Shelley Wright, now an assistant professor of physics at UC San Diego, discusses the dichroic filter of the NIROSETI instrument. (Photo by Laurie Hatch)

    Frank Drake, professor emeritus of astronomy and astrophysics at UC Santa Cruz and director emeritus of the SETI Institute, said there are several additional advantages to a search in the infrared realm.

    “The signals are so strong that we only need a small telescope to receive them. Smaller telescopes can offer more observational time, and that is good because we need to search many stars for a chance of success,” said Drake.

    The only downside is that extraterrestrials would need to be transmitting their signals in our direction, Drake said, though he sees this as a positive side to that limitation. “If we get a signal from someone who’s aiming for us, it could mean there’s altruism in the universe. I like that idea. If they want to be friendly, that’s who we will find.”

    Scientists have searched the skies for radio signals for more than 50 years and expanded their search into the optical realm more than a decade ago. The idea of searching in the infrared is not a new one, but instruments capable of capturing pulses of infrared light only recently became available.

    “We had to wait,” Wright said. “I spent eight years waiting and watching as new technology emerged.”

    Now that technology has caught up, the search will extend to stars thousands of light years away, rather than just hundreds. NIROSETI, or Near-Infrared Optical Search for Extraterrestrial Intelligence, could also uncover new information about the physical universe.

    “This is the first time Earthlings have looked at the universe at infrared wavelengths with nanosecond time scales,” said Dan Werthimer, UC Berkeley SETI Project Director. “The instrument could discover new astrophysical phenomena, or perhaps answer the question of whether we are alone.”

    NIROSETI will also gather more information than previous optical detectors by recording levels of light over time so that patterns can be analyzed for potential signs of other civilizations.

    “Searching for intelligent life in the universe is both thrilling and somewhat unorthodox,” said Claire Max, director of UC Observatories and professor of astronomy and astrophysics at UC Santa Cruz. “Lick Observatory has already been the site of several previous SETI searches, so this is a very exciting addition to the current research taking place.”

    NIROSETI will be fully operational by early summer and will scan the skies several times a week on the Nickel 1-meter telescope at Lick Observatory, located on Mt. Hamilton east of San Jose.

    The NIROSETI team also includes Geoffrey Marcy and Andrew Siemion from UC Berkeley; Patrick Dorval, a Dunlap undergraduate, and Elliot Meyer, a Dunlap graduate student; and Richard Treffers of Starman Systems. Funding for the project comes from the generous support of Bill and Susan Bloomfield.

     
  • richardmitnick 2:55 pm on May 9, 2018 Permalink | Reply
    Tags: Astronomers find an exoplanet atmosphere free of clouds, , , , , UCSC-UC Santa Cruz, WASP-96b   

    From UC Santa Cruz: “Astronomers find an exoplanet atmosphere free of clouds” 

    UC Santa Cruz

    From UC Santa Cruz

    May 07, 2018
    Tim Stephens
    stephens@ucsc.edu

    1
    Transiting exoplanet. Exoplanets in orbits close to the line of sight for us on Earth periodically pass in front of (transit) and behind (secondary eclipse) their host stars. Transits and eclipses are a powerful indirect way to study the composition of exoplanet atmospheres. (Image credit: N. Nikolov)

    An international team of astronomers has detected an exoplanet atmosphere that is free of clouds, marking a pivotal breakthrough in the quest to better understand what lies at the outer reaches of our galaxy.

    Using Europe’s 8.2-meter Very Large Telescope in Chile, the team studied the atmosphere of the planet WASP-96b when it passed in front of its host star.

    ESO VLT Platform at Cerro Paranal elevation 2,635 m (8,645 ft)

    This enabled the researchers to measure the decrease of starlight caused by the planet and its atmosphere and thereby determine the planet’s atmospheric composition. The researchers published their findings May 7 in Nature.

    Clouds and hazes are known to exist in the atmospheres of some of the hottest and coldest solar system planets and exoplanets. The presence or absence of clouds and their ability to block light plays an important role in the overall energy budget of planetary atmospheres.

    “It is difficult to predict which of these hot atmospheres will have thick clouds. By seeing the full range of possible atmospheres, from very cloudy to nearly cloud-free like WASP-96b, we’ll gain a better understanding of what these clouds are made of,” explained coauthor Jonathan Fortney, professor of astronomy and astrophysics at UC Santa Cruz.

    2
    Sodium fingerprint in an exoplanet spectrum. Shown is the absorption due to sodium at each wavelength. More absorption means that we are looking higher up in the atmosphere, and the vertical axis is therefore a measure of altitude in the atmosphere of the planet. An atmosphere free of clouds produces an intact sodium fingerprint (left panel). A cloud deck blocks part of the sodium in the atmosphere, partially removing its spectral signature (right panel). (Image credit: N. Nikolov/E. de Mooij)

    Just like an individual’s fingerprints are unique, atoms and molecules have a unique spectral characteristic that can be used to detect their presence in celestial objects. The spectrum of WASP-96b shows the complete fingerprint of sodium, which can only be observed for an atmosphere free of clouds.

    “We’ve been looking at over twenty exoplanet transit spectra. WASP-96b is the only exoplanet that appears to be entirely cloud-free and shows such a clear sodium signature, making the planet a benchmark for characterization,” said lead investigator Nikolay Nikolov from the University of Exeter in the United Kingdom.

    WASP-96b is a typical hot gas-giant exoplanet, similar to Saturn in mass but with a much larger radius, exceeding the size of Jupiter by 20 percent. The planet periodically transits a sun-like star 980 light years away in the southern constellation Phoenix, halfway between the southern jewels Fomalhaut (α Piscis Austrini) and Achernar (α Eridani).

    It has long been predicted that sodium exists in the atmospheres of hot gas-giant exoplanets, and in a cloud-free atmosphere it would produce spectra that are similar in shape to the profile of a camping tent.

    “Until now, sodium was revealed either as a very narrow peak or found to be completely missing,” Nikolov said. “This is because the characteristic ‘tent-shaped’ profile can only be produced deep in the atmosphere of the planet, and for most planets, clouds appear to get in the way.”

    The sodium signature seen in WASP-96b suggests an atmosphere free of clouds. The observation allowed the team to measure how abundant sodium is in the atmosphere of the planet, finding levels similar to those found in our own solar system.

    “WASP-96b will also provide us with a unique opportunity to determine the abundances of other molecules, such as water, carbon monoxide, and carbon dioxide, with future observations,” said coauthor Ernst de Mooij of Dublin City University.

    The team aims to look at the signatures of these other molecules in the atmosphere of WASP-96b with the Hubble and James Webb Space Telescopes as well as with ground-based telescopes.

    NASA/ESA Hubble Telescope

    NASA/ESA/CSA Webb Telescope annotated

    See the full article here .

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    UCO Lick Shane Telescope
    UCO Lick Shane Telescope interior
    Shane Telescope at UCO Lick Observatory, UCSC

    Lick Automated Planet Finder telescope, Mount Hamilton, CA, USA

    Lick Automated Planet Finder telescope, Mount Hamilton, CA, USA

    UC Santa Cruz campus
    The University of California, Santa Cruz, opened in 1965 and grew, one college at a time, to its current (2008-09) enrollment of more than 16,000 students. Undergraduates pursue more than 60 majors supervised by divisional deans of humanities, physical & biological sciences, social sciences, and arts. Graduate students work toward graduate certificates, master’s degrees, or doctoral degrees in more than 30 academic fields under the supervision of the divisional and graduate deans. The dean of the Jack Baskin School of Engineering oversees the campus’s undergraduate and graduate engineering programs.

    UCSC is the home base for the Lick Observatory.

    Lick Observatory's Great Lick 91-centimeter (36-inch) telescope housed in the South (large) Dome of main building
    Lick Observatory’s Great Lick 91-centimeter (36-inch) telescope housed in the South (large) Dome of main building

    Search for extraterrestrial intelligence expands at Lick Observatory
    New instrument scans the sky for pulses of infrared light
    March 23, 2015
    By Hilary Lebow
    1
    The NIROSETI instrument saw first light on the Nickel 1-meter Telescope at Lick Observatory on March 15, 2015. (Photo by Laurie Hatch) UCSC Lick Nickel telescope

    Astronomers are expanding the search for extraterrestrial intelligence into a new realm with detectors tuned to infrared light at UC’s Lick Observatory. A new instrument, called NIROSETI, will soon scour the sky for messages from other worlds.

    “Infrared light would be an excellent means of interstellar communication,” said Shelley Wright, an assistant professor of physics at UC San Diego who led the development of the new instrument while at the University of Toronto’s Dunlap Institute for Astronomy & Astrophysics.

    Wright worked on an earlier SETI project at Lick Observatory as a UC Santa Cruz undergraduate, when she built an optical instrument designed by UC Berkeley researchers. The infrared project takes advantage of new technology not available for that first optical search.

    Infrared light would be a good way for extraterrestrials to get our attention here on Earth, since pulses from a powerful infrared laser could outshine a star, if only for a billionth of a second. Interstellar gas and dust is almost transparent to near infrared, so these signals can be seen from great distances. It also takes less energy to send information using infrared signals than with visible light.

    5
    UCSC alumna Shelley Wright, now an assistant professor of physics at UC San Diego, discusses the dichroic filter of the NIROSETI instrument. (Photo by Laurie Hatch)

    Frank Drake, professor emeritus of astronomy and astrophysics at UC Santa Cruz and director emeritus of the SETI Institute, said there are several additional advantages to a search in the infrared realm.

    “The signals are so strong that we only need a small telescope to receive them. Smaller telescopes can offer more observational time, and that is good because we need to search many stars for a chance of success,” said Drake.

    The only downside is that extraterrestrials would need to be transmitting their signals in our direction, Drake said, though he sees this as a positive side to that limitation. “If we get a signal from someone who’s aiming for us, it could mean there’s altruism in the universe. I like that idea. If they want to be friendly, that’s who we will find.”

    Scientists have searched the skies for radio signals for more than 50 years and expanded their search into the optical realm more than a decade ago. The idea of searching in the infrared is not a new one, but instruments capable of capturing pulses of infrared light only recently became available.

    “We had to wait,” Wright said. “I spent eight years waiting and watching as new technology emerged.”

    Now that technology has caught up, the search will extend to stars thousands of light years away, rather than just hundreds. NIROSETI, or Near-Infrared Optical Search for Extraterrestrial Intelligence, could also uncover new information about the physical universe.

    “This is the first time Earthlings have looked at the universe at infrared wavelengths with nanosecond time scales,” said Dan Werthimer, UC Berkeley SETI Project Director. “The instrument could discover new astrophysical phenomena, or perhaps answer the question of whether we are alone.”

    NIROSETI will also gather more information than previous optical detectors by recording levels of light over time so that patterns can be analyzed for potential signs of other civilizations.

    “Searching for intelligent life in the universe is both thrilling and somewhat unorthodox,” said Claire Max, director of UC Observatories and professor of astronomy and astrophysics at UC Santa Cruz. “Lick Observatory has already been the site of several previous SETI searches, so this is a very exciting addition to the current research taking place.”

    NIROSETI will be fully operational by early summer and will scan the skies several times a week on the Nickel 1-meter telescope at Lick Observatory, located on Mt. Hamilton east of San Jose.

    The NIROSETI team also includes Geoffrey Marcy and Andrew Siemion from UC Berkeley; Patrick Dorval, a Dunlap undergraduate, and Elliot Meyer, a Dunlap graduate student; and Richard Treffers of Starman Systems. Funding for the project comes from the generous support of Bill and Susan Bloomfield.

     
  • richardmitnick 3:27 pm on April 6, 2018 Permalink | Reply
    Tags: , , , , , UCSC-UC Santa Cruz, Virginia Trimble, ,   

    From UCSC and UC Irvine via WIRED: Women in STEM – “The Woman Who Knows Everything About the Universe” Virginia Trimble 

    UC Santa Cruz

    UC Santa Cruz

    UC Irvine bloc

    UC Irvine

    WIRED

    1
    For 16 years, Virginia Trimble read every astronomy paper in 23 journals. Now, her review papers are part of the canon. Universitat de València.

    In 1965, physicist Richard Feynman was busy.

    Richard Feynman © Open University

    He was busy winning the Nobel Prize, and he was busy learning to draw. One day during that productive time in his life, he saw astrophysics student Virginia Trimble striding across Caltech’s campus and thought, There’s a good model.

    Soon, she was posing for him a couple Tuesdays a month, in exchange for $5.50 each session and a lot of physics talk. She was studying a nebula, and he was, sometimes, sharing anecdotes that would later appear in one of his books, which featured everything from his bongo playing to his work on the Manhattan Project. Treatment of women in professional and academic situations has changed—and significantly so—since those sixties-California-campus days. Trimble was a student at a university that enrolled few women, in a field that enlisted few women. But her experience at Caltech wasn’t limited to sidelining model gigs. Those early days of learning and research were the beginning of a five-decade career that has turned Trimble into a powerhouse of astronomy.

    I first encountered Trimble’s work when I was an undergraduate astrophysics major. On the first day of seminar, my professor handed out a 101-page stack of paper. Flipping through its 13 sections, he explained that Trimble trawled the scientific journals and collated the year’s cosmic progress into a tome like this one. It wasn’t just a review paper laying out the state of atmospheric studies of Jupiter, or asteroid hunting, or massive star formation. It was all of everything important that had happened the previous year in astronomy—broad, comprehensive, and utterly unusual. Most unusual of all was that it contained jokes.

    Today, new technologies promise to synthesize masses of publication data for scientists. But before artificial intelligence even tried, astronomers had Trimble, who wrote these comprehensive articles every year. For 16 years, she devoted her mind to this task of curation, contextualization, and commentary. And throughout her career, she has largely eschewed long-term research with fancy telescopes, competitive funding, and approving nods from university administrators. Refusing narrow focus, she has gone solo on most of her 850 publications, focusing as much on the nature of doing astronomy as studying the universe itself.

    “I just asked questions,” she says, “and sometimes found a way to answer them.” That’s business as usual for Trimble, who has spent much of her career branching off from the already thin bough of bushwhacking female astronomers.

    When Trimble enrolled at UCLA in the 1960s, she wanted to major in archaeology. But the school only offered that field of study to graduate students. Right there in the A section of the catalog, though, was “astronomy,” a topic that her father informed her she’d always been interested in.

    So she enrolled as an astronomy student, living at home while attending the university’s gifted program. Which she was—gifted. In a 1962 LIFE package about California’s educational system, a journalist profiled Trimble for a piece called Behind a Lovely Face, a 180 I.Q. The title acted surprised that a pretty lady might also have a productive brain—but Trimble quickly made it clear that people should cease to be surprised at her smarts.

    Trimble’s father was right, and she felt drawn to the mysteries of the universe. After she finished her undergraduate degree, Trimble was accepted to a PhD program at Caltech. “It was only later that I looked in their catalog and saw that women were only admitted under exceptional circumstances,” she says, “exceptional” usually meaning “married to a male Caltech admittee.” There, Trimble studied the Crab Nebula, the dust, gas, and plasma sent speeding into space during a supernova explosion whose light reached Earth in 1054.

    Supernova remnant Crab nebula. NASA/ESA Hubble

    To work on this project, she applied for time at Palomar Observatory, an iconic be-domed telescope east of San Diego.


    Caltech Palomar Observatory, located in San Diego County, California, US, at 1,712 m (5,617 ft)

    She was only the third woman to use the telescope, and only the second to actually be granted her own time on it (Vera Rubin, a dark-matter pioneer, was the first).

    Vera Rubin measuring spectra (Emilio Segre Visual Archives AIP SPL)

    Astronomer Vera Rubin at the Lowell Observatory in 1965. (The Carnegie Institution for Science)

    The nebula’s contents are still, these centuries later, lit. They beam out bright radiation across a spectrum of wavelengths. Today, scientists know that a pulsar—the corpse of a massive star, as dense as an atomic nucleus and the size of a city, spinning 30 times a second—lurks at the center and energizes it. But back when Trimble was doing her dissertation, pulsars were just being discovered, and no one knew the Crab hosted one. “It was quite a mystery what kept the thing as bright as it is now,” she says.

    For her doctoral work, she measured the motions of the nebula’s filaments, and found, among other things, that the gas had sped up its flight from the center of the explosion since that explosion had happened (weird!) and that it was around 6,500 light-years away. Discovery was all right, but its details—so many photographic plates, so many similar, tedious observations—wasn’t the most fun. She sang, danced, on the side, to liven life up. But did she enjoy the telescope part? I ask. Going to a mountaintop, commanding a large instrument, gathering her own data about the universe with her own hands?

    “Noooooo,” she says. “It was cold, and I hate being cold.”

    Trimble soon realized she didn’t want to look at the Crab Nebula—or at supernova remnants more generally, or at anything, really—for the rest of her life. She preferred independence to teams. She didn’t want to hand a bunch of her grant money over to UC Irvine, where she became a tenured astronomer. So, instead of all that, she started publishing papers that took an aerial view of the field of astronomy.

    Like any scientist, she liked to wonder. And, when people began asking her to give big talks at conferences, she started wondering more about how science gets made, and why, and by whom. “I always figured this was my opportunity to say something that might not otherwise not get said,” she says. So instead of, say, summarizing the conference’s topic, she analyzed big-picture questions: How did this sub-field become interesting? Why are we worrying about this particular research subject now? Whose work did we leave out at this meeting?

    She wondered whether it paid to go to a good graduate school, in terms of career advancement (it did). She wondered which telescopes birthed the most papers, and found that a huge number of papers came from non-celebrity instruments. She wondered about the narrative arc that led to scientific consensus, and wrote a paper that tracked the progress of different scientific debates—over things like the nature of Jupiter’s Great Red Spot and the existence of dark matter.

    And then there was that time she trolled her colleagues, publishing this paper suggesting that the blue star next to a suspected black hole—the first real black hole candidate—was smaller than people thought. If that was true, it would also mean the black hole was smaller. Too small, in fact, to be a black hole at all. Two different groups instantly set out to prove her incorrect.

    “I knew it was wrong when I suggested doing it,” she says. “It was a way to get people to go out and do observations.”

    Much of her work seems to demand that astronomers think differently, perhaps situate themselves a little more, rather than imagining that their research is standalone, decoupled from larger culture. She’s recently been working, for instance, on a series about how World War I influenced the development of general relativity, and on a chapter for a book about people who maybe should have won the Nobel Prize and didn’t.

    “Is it fun?” I ask.

    “It’s certainly fun,” she says, “or I wouldn’t do it.”

    If Trimble was asking questions other astronomers didn’t think of, or at least didn’t investigate, it may have been because she knew so much more than them. Each year starting in 1991, she read every article—every one—in 23 journals. “I quickly decided whether this was anything I would ever want to know about again,” she says. If it was, it got a line in her notebook (two lines if it was super interesting). When it came time to write, she’d go back to her notebook, cull a bit, organize the entries into topics, and then write what was essentially a historical record of that annum, with the year’s accumulated cosmic knowledge.

    Here’s what she liked best about it: “I got to tell these nasty jokes,” she says. Like this one, from the 2005 paper that I read in college: “If every galaxy has [a black hole], why do people talk about them so much? Well, the same could probably be said about human private parts, which also have in common with black holes a central location and, as a rule, concealing material around.”

    But around 2007, editorial interest in the review declined, around the same time that printing and reading journal articles on paper went out of fashion. “I can’t read 6,000 papers online,” she says. Staring at a screen that long is intense. “I start seeing jagged lightning patterns,” she says.

    Now, no single person knows what all the world’s astronomers do all day. And it would be hard for a younger scientist to take Trimble’s task on again: Academic science doesn’t value broad-mindedness, in practice. It’s a publish or perish world full of big collaborations, in which most people nest in their niche of the knowledge-creation establishment.

    But despite that, the larger astronomical community seems to agree that Trimble’s contributions were valuable. Trimble has been a vice president within the International Astronomical Union and the vice president of the American Astronomical Society, which also gave her the George Van Biesbroeck prize, “for long-term extraordinary or unselfish service to astronomy.” The American Association of Physics Teachers gave her its Klopsteg Memorial Lecture Award, which “recognizes outstanding communication of the excitement of contemporary physics to the general public.”

    But, perhaps most fittingly, the International Astronomical Union recently named an asteroid after her. Now called 9271Trimble, the space rock travels solo, within a belt of others like itself.

    When I called to interview Trimble for this article, she asked if I received the 40 or so scanned pages she sent—the beginning of her memoir. In it, she recounts those posing sessions at Caltech. Feynman “didn’t like silence,” Trimble wrote, so he talked, and sometimes listened. “Heard many of the anecdotes that appear in Surely You’re Joking,” she continued, referring to Feynman’s most-famous book, “and some that don’t.”

    The memoir is obviously unfinished, she says—dozens of pages and not even past her early years. “I got bored,” she explains. “I just got bored.” It was never, after all, Trimble’s style to stick to one topic.

    See the full article here .

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    UC Irvine Campus

    Since 1965, the University of California, Irvine has combined the strengths of a major research university with the bounty of an incomparable Southern California location. UCI’s unyielding commitment to rigorous academics, cutting-edge research, and leadership and character development makes the campus a driving force for innovation and discovery that serves our local, national and global communities in many ways.

    With more than 29,000 undergraduate and graduate students, 1,100 faculty and 9,400 staff, UCI is among the most dynamic campuses in the University of California system. Increasingly a first-choice campus for students, UCI ranks among the top 10 U.S. universities in the number of undergraduate applications and continues to admit freshmen with highly competitive academic profiles.

    UCI fosters the rigorous expansion and creation of knowledge through quality education. Graduates are equipped with the tools of analysis, expression and cultural understanding necessary for leadership in today’s world.

    Consistently ranked among the nation’s best universities – public and private – UCI excels in a broad range of fields, garnering national recognition for many schools, departments and programs. Times Higher Education ranked UCI No. 1 among universities in the U.S. under 50 years old. Three UCI researchers have won Nobel Prizes – two in chemistry and one in physics.

    The university is noted for its top-rated research and graduate programs, extensive commitment to undergraduate education, and growing number of professional schools and programs of academic and social significance. Recent additions include highly successful programs in public health, pharmaceutical sciences and nursing science; an expanding education school; and a law school already ranked among the nation’s top 10 for its scholarly impact.

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    UC Santa Cruz

    UC Santa Cruz

    See the full article here .

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    UCO Lick Shane Telescope
    UCO Lick Shane Telescope interior
    Shane Telescope at UCO Lick Observatory, UCSC

    Lick Automated Planet Finder telescope, Mount Hamilton, CA, USA

    Lick Automated Planet Finder telescope, Mount Hamilton, CA, USA

    UC Santa Cruz campus
    The University of California, Santa Cruz, opened in 1965 and grew, one college at a time, to its current (2008-09) enrollment of more than 16,000 students. Undergraduates pursue more than 60 majors supervised by divisional deans of humanities, physical & biological sciences, social sciences, and arts. Graduate students work toward graduate certificates, master’s degrees, or doctoral degrees in more than 30 academic fields under the supervision of the divisional and graduate deans. The dean of the Jack Baskin School of Engineering oversees the campus’s undergraduate and graduate engineering programs.

    UCSC is the home base for the Lick Observatory.

    Lick Observatory's Great Lick 91-centimeter (36-inch) telescope housed in the South (large) Dome of main building
    Lick Observatory’s Great Lick 91-centimeter (36-inch) telescope housed in the South (large) Dome of main building

    Search for extraterrestrial intelligence expands at Lick Observatory
    New instrument scans the sky for pulses of infrared light
    March 23, 2015
    By Hilary Lebow
    1
    The NIROSETI instrument saw first light on the Nickel 1-meter Telescope at Lick Observatory on March 15, 2015. (Photo by Laurie Hatch) UCSC Lick Nickel telescope

    Astronomers are expanding the search for extraterrestrial intelligence into a new realm with detectors tuned to infrared light at UC’s Lick Observatory. A new instrument, called NIROSETI, will soon scour the sky for messages from other worlds.

    “Infrared light would be an excellent means of interstellar communication,” said Shelley Wright, an assistant professor of physics at UC San Diego who led the development of the new instrument while at the University of Toronto’s Dunlap Institute for Astronomy & Astrophysics.

    Wright worked on an earlier SETI project at Lick Observatory as a UC Santa Cruz undergraduate, when she built an optical instrument designed by UC Berkeley researchers. The infrared project takes advantage of new technology not available for that first optical search.

    Infrared light would be a good way for extraterrestrials to get our attention here on Earth, since pulses from a powerful infrared laser could outshine a star, if only for a billionth of a second. Interstellar gas and dust is almost transparent to near infrared, so these signals can be seen from great distances. It also takes less energy to send information using infrared signals than with visible light.

    5
    UCSC alumna Shelley Wright, now an assistant professor of physics at UC San Diego, discusses the dichroic filter of the NIROSETI instrument. (Photo by Laurie Hatch)

    Frank Drake, professor emeritus of astronomy and astrophysics at UC Santa Cruz and director emeritus of the SETI Institute, said there are several additional advantages to a search in the infrared realm.

    “The signals are so strong that we only need a small telescope to receive them. Smaller telescopes can offer more observational time, and that is good because we need to search many stars for a chance of success,” said Drake.

    The only downside is that extraterrestrials would need to be transmitting their signals in our direction, Drake said, though he sees this as a positive side to that limitation. “If we get a signal from someone who’s aiming for us, it could mean there’s altruism in the universe. I like that idea. If they want to be friendly, that’s who we will find.”

    Scientists have searched the skies for radio signals for more than 50 years and expanded their search into the optical realm more than a decade ago. The idea of searching in the infrared is not a new one, but instruments capable of capturing pulses of infrared light only recently became available.

    “We had to wait,” Wright said. “I spent eight years waiting and watching as new technology emerged.”

    Now that technology has caught up, the search will extend to stars thousands of light years away, rather than just hundreds. NIROSETI, or Near-Infrared Optical Search for Extraterrestrial Intelligence, could also uncover new information about the physical universe.

    “This is the first time Earthlings have looked at the universe at infrared wavelengths with nanosecond time scales,” said Dan Werthimer, UC Berkeley SETI Project Director. “The instrument could discover new astrophysical phenomena, or perhaps answer the question of whether we are alone.”

    NIROSETI will also gather more information than previous optical detectors by recording levels of light over time so that patterns can be analyzed for potential signs of other civilizations.

    “Searching for intelligent life in the universe is both thrilling and somewhat unorthodox,” said Claire Max, director of UC Observatories and professor of astronomy and astrophysics at UC Santa Cruz. “Lick Observatory has already been the site of several previous SETI searches, so this is a very exciting addition to the current research taking place.”

    NIROSETI will be fully operational by early summer and will scan the skies several times a week on the Nickel 1-meter telescope at Lick Observatory, located on Mt. Hamilton east of San Jose.

    The NIROSETI team also includes Geoffrey Marcy and Andrew Siemion from UC Berkeley; Patrick Dorval, a Dunlap undergraduate, and Elliot Meyer, a Dunlap graduate student; and Richard Treffers of Starman Systems. Funding for the project comes from the generous support of Bill and Susan Bloomfield.

     
  • richardmitnick 2:57 pm on January 25, 2018 Permalink | Reply
    Tags: Swinburne deepens University of California Santa Cruz relationship, , UCSC-UC Santa Cruz   

    From Swinburne University: “Swinburne deepens University of California Santa Cruz relationship” 

    Swinburne U bloc

    Swinburne University

    25 January 2018

    Nick Adams
    +61 3 9214 4524
    nadams@swin.edu.au

    Swinburne continues to focus on global research with impact, as it strengthened its research partnership with one of North America’s top ranked universities, the University of California Santa Cruz (UCSC).

    During a recent visit to UCSC, senior members from Swinburne and UCSC discussed the approach and agreed on key principles for an ongoing research collaboration and partnered PhD program, primarily in the field of astronomy, with plans to expand it to data science and machine learning in the near future.

    Swinburne Deputy-Vice Chancellor (Research and Development) Professor Aleksandar Subic says the research collaboration will drive world-leading research outcomes.

    “This is the first time Swinburne has agreed to develop a partnered PhD program with a university in the United States and we are thrilled that we could do it with one of the global leaders in astronomy research – the University of California Santa Cruz,” he says.

    “By building on existing relationships between researchers from Swinburne’s Centre for Astrophysics and Supercomputing and UCSC we will be able to build on our shared areas of research expertise including galaxy evolution, cosmology, properties of nearby galaxies, astrophysics and star formation.”

    Deepening research engagement in North America

    The close relationship with UCSC is the latest in a series of strategic partnerships and collaborations for Swinburne with universities and organisations in Silicon Valley and the greater California.

    Earlier in 2018, Swinburne announced that it was the first university to have a presence in CSIRO’s Silicon Valley headquarters, paving the way for Australia-US innovation partnerships.

    “Swinburne has made a conscious effort to collaborate and partner with regions of the world that are leading the way in research, innovation and commercialisation,” says Professor Subic.

    “We are serious about expanding our global research networks and partnerships with the most advanced innovation ecosystems around the world, like we have with Tel Aviv and now Silicon Valley.

    “Our relationship with UCSC is the beginning of what we expect to be a long-standing, impactful partnership in this region.”

    See the full article here .

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    Swinburne U Campus

    Swinburne is a large and culturally diverse organisation. A desire to innovate and bring about positive change motivates our students and staff. The result is in an institution that grows and evolves each year.

     
  • richardmitnick 2:17 pm on January 1, 2018 Permalink | Reply
    Tags: , , , , , Supermassive black holes control star formation in large galaxies, UCSC-UC Santa Cruz   

    From UCSC: “Supermassive black holes control star formation in large galaxies” 

    UC Santa Cruz

    UC Santa Cruz

    January 01, 2018
    Tim Stephens
    stephens@ucsc.edu

    1
    This artist’s concept depicts a supermassive black hole at the center of a galaxy. The blue color here represents radiation pouring out from material very close to the black hole. The grayish structure surrounding the black hole, called a torus, is made up of gas and dust. Credit: NASA/JPL-Caltech.

    2
    The power of a supermassive black hole is seen in this image of Centaurus A, one of the active galactic nuclei closest to Earth. The image combines data from several telescopes at different wavelengths, showing jets and lobes powered by the supermassive black hole at the center of the galaxy. Image credit: ESO/WFI (Optical); MPIfR/ESO/APEX/A.Weiss et al. (Submillimetre); NASA/CXC/CfA/R.Kraft et al. (X-ray)

    ESO WFI LaSilla 2.2-m MPG/ESO telescope at La Silla, 600 km north of Santiago de Chile at an altitude of 2400 metres

    MPG/ESO 2.2 meter telescope at Cerro La Silla, Chile, 600 km north of Santiago de Chile at an altitude of 2400 metres

    ESO/APEX high on the Chajnantor plateau in Chile’s Atacama region, at an altitude of over 4,800 m (15,700 ft)

    NASA/Chandra Telescope

    Young galaxies blaze with bright new stars forming at a rapid rate, but star formation eventually shuts down as a galaxy evolves. A new study, published January 1, 2018, in Nature, shows that the mass of the black hole in the center of the galaxy determines how soon this “quenching” of star formation occurs.

    Every massive galaxy has a central supermassive black hole, more than a million times more massive than the sun, revealing its presence through its gravitational effects on the galaxy’s stars and sometimes powering the energetic radiation from an active galactic nucleus (AGN). The energy pouring into a galaxy from an active galactic nucleus is thought to turn off star formation by heating and dispelling the gas that would otherwise condense into stars as it cooled.

    This idea has been around for decades, and astrophysicists have found that simulations of galaxy evolution must incorporate feedback from the black hole in order to reproduce the observed properties of galaxies. But observational evidence of a connection between supermassive black holes and star formation has been lacking, until now.

    “We’ve been dialing in the feedback to make the simulations work out, without really knowing how it happens,” said Jean Brodie, professor of astronomy and astrophysics at UC Santa Cruz and a coauthor of the paper. “This is the first direct observational evidence where we can see the effect of the black hole on the star formation history of the galaxy.”

    The new results reveal a continuous interplay between black hole activity and star formation throughout a galaxy’s life, affecting every generation of stars formed as the galaxy evolves.

    Led by first author Ignacio Martín-Navarro, a postdoctoral researcher at UC Santa Cruz, the study focused on massive galaxies for which the mass of the central black hole had been measured in previous studies by analyzing the motions of stars near the center of the galaxy. To determine the star formation histories of the galaxies, Martín-Navarro analyzed detailed spectra of their light obtained by the Hobby-Eberly Telescope Massive Galaxy Survey.

    U Texas Austin McDonald Observatory Hobby-Eberly Telescope, Altitude 2,026 m (6,647 ft)

    Spectroscopy enables astronomers to separate and measure the different wavelengths of light from an object. Martín-Navarro used computational techniques to analyze the spectrum of each galaxy and recover its star formation history by finding the best combination of stellar populations to fit the spectroscopic data. “It tells you how much light is coming from stellar populations of different ages,” he said.

    When he compared the star formation histories of galaxies with black holes of different masses, he found striking differences. These differences only correlated with black hole mass and not with galactic morphology, size, or other properties.

    “For galaxies with the same mass of stars but different black hole mass in the center, those galaxies with bigger black holes were quenched earlier and faster than those with smaller black holes. So star formation lasted longer in those galaxies with smaller central black holes,” Martín-Navarro said.

    Other researchers have looked for correlations between star formation and the luminosity of active galactic nuclei, without success. Martín-Navarro said that may be because the time scales are so different, with star formation occurring over hundreds of millions of years, while outbursts from active galactic nuclei occur over shorter periods of time.

    A supermassive black hole is only luminous when it is actively gobbling up matter from its host galaxy’s inner regions. Active galactic nuclei are highly variable and their properties depend on the size of the black hole, the rate of accretion of new material falling onto the black hole, and other factors.

    “We used black hole mass as a proxy for the energy put into the galaxy by the AGN, because accretion onto more massive black holes leads to more energetic feedback from active galactic nuclei, which would quench star formation faster,” Martín-Navarro explained.

    The precise nature of the feedback from the black hole that quenches star formation remains uncertain, according to coauthor Aaron Romanowsky, an astronomer at San Jose State University and UC Observatories.

    “There are different ways a black hole can put energy out into the galaxy, and theorists have all kinds of ideas about how quenching happens, but there’s more work to be done to fit these new observations into the models,” Romanowsky said.

    In addition to Martín-Navarro, Brodie, and Romanowsky, the coauthors of the paper include Tomás Ruiz Lara at the Institute of Astrophysics of the Canary Islands in Tenerife, Spain, and Glenn van de Ven at UC Observatories and the European Southern Observatory. This research was funded by the U.S. National Science Foundation, the Spanish Ministry of Economy and Competitiveness, and the European Union Horizon 2020 research and innovation program.

    See the full article here .

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    UCO Lick Shane Telescope
    UCO Lick Shane Telescope interior
    Shane Telescope at UCO Lick Observatory, UCSC

    Lick Automated Planet Finder telescope, Mount Hamilton, CA, USA

    Lick Automated Planet Finder telescope, Mount Hamilton, CA, USA

    UC Santa Cruz campus
    The University of California, Santa Cruz, opened in 1965 and grew, one college at a time, to its current (2008-09) enrollment of more than 16,000 students. Undergraduates pursue more than 60 majors supervised by divisional deans of humanities, physical & biological sciences, social sciences, and arts. Graduate students work toward graduate certificates, master’s degrees, or doctoral degrees in more than 30 academic fields under the supervision of the divisional and graduate deans. The dean of the Jack Baskin School of Engineering oversees the campus’s undergraduate and graduate engineering programs.

    UCSC is the home base for the Lick Observatory.

    Lick Observatory's Great Lick 91-centimeter (36-inch) telescope housed in the South (large) Dome of main building
    Lick Observatory’s Great Lick 91-centimeter (36-inch) telescope housed in the South (large) Dome of main building

    Search for extraterrestrial intelligence expands at Lick Observatory
    New instrument scans the sky for pulses of infrared light
    March 23, 2015
    By Hilary Lebow
    1
    The NIROSETI instrument saw first light on the Nickel 1-meter Telescope at Lick Observatory on March 15, 2015. (Photo by Laurie Hatch) UCSC Lick Nickel telescope

    Astronomers are expanding the search for extraterrestrial intelligence into a new realm with detectors tuned to infrared light at UC’s Lick Observatory. A new instrument, called NIROSETI, will soon scour the sky for messages from other worlds.

    “Infrared light would be an excellent means of interstellar communication,” said Shelley Wright, an assistant professor of physics at UC San Diego who led the development of the new instrument while at the University of Toronto’s Dunlap Institute for Astronomy & Astrophysics.

    Wright worked on an earlier SETI project at Lick Observatory as a UC Santa Cruz undergraduate, when she built an optical instrument designed by UC Berkeley researchers. The infrared project takes advantage of new technology not available for that first optical search.

    Infrared light would be a good way for extraterrestrials to get our attention here on Earth, since pulses from a powerful infrared laser could outshine a star, if only for a billionth of a second. Interstellar gas and dust is almost transparent to near infrared, so these signals can be seen from great distances. It also takes less energy to send information using infrared signals than with visible light.

    5
    UCSC alumna Shelley Wright, now an assistant professor of physics at UC San Diego, discusses the dichroic filter of the NIROSETI instrument. (Photo by Laurie Hatch)

    Frank Drake, professor emeritus of astronomy and astrophysics at UC Santa Cruz and director emeritus of the SETI Institute, said there are several additional advantages to a search in the infrared realm.

    “The signals are so strong that we only need a small telescope to receive them. Smaller telescopes can offer more observational time, and that is good because we need to search many stars for a chance of success,” said Drake.

    The only downside is that extraterrestrials would need to be transmitting their signals in our direction, Drake said, though he sees this as a positive side to that limitation. “If we get a signal from someone who’s aiming for us, it could mean there’s altruism in the universe. I like that idea. If they want to be friendly, that’s who we will find.”

    Scientists have searched the skies for radio signals for more than 50 years and expanded their search into the optical realm more than a decade ago. The idea of searching in the infrared is not a new one, but instruments capable of capturing pulses of infrared light only recently became available.

    “We had to wait,” Wright said. “I spent eight years waiting and watching as new technology emerged.”

    Now that technology has caught up, the search will extend to stars thousands of light years away, rather than just hundreds. NIROSETI, or Near-Infrared Optical Search for Extraterrestrial Intelligence, could also uncover new information about the physical universe.

    “This is the first time Earthlings have looked at the universe at infrared wavelengths with nanosecond time scales,” said Dan Werthimer, UC Berkeley SETI Project Director. “The instrument could discover new astrophysical phenomena, or perhaps answer the question of whether we are alone.”

    NIROSETI will also gather more information than previous optical detectors by recording levels of light over time so that patterns can be analyzed for potential signs of other civilizations.

    “Searching for intelligent life in the universe is both thrilling and somewhat unorthodox,” said Claire Max, director of UC Observatories and professor of astronomy and astrophysics at UC Santa Cruz. “Lick Observatory has already been the site of several previous SETI searches, so this is a very exciting addition to the current research taking place.”

    NIROSETI will be fully operational by early summer and will scan the skies several times a week on the Nickel 1-meter telescope at Lick Observatory, located on Mt. Hamilton east of San Jose.

    The NIROSETI team also includes Geoffrey Marcy and Andrew Siemion from UC Berkeley; Patrick Dorval, a Dunlap undergraduate, and Elliot Meyer, a Dunlap graduate student; and Richard Treffers of Starman Systems. Funding for the project comes from the generous support of Bill and Susan Bloomfield.

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    UCSC is the home base for the Lick Observatory.

     
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