From The California Institute of Technology (US): “Colossal Black Holes Locked in Dance at Heart of Galaxy”

From The California Institute of Technology (US)

February 23, 2022
Whitney Clavin
(626) 395‑1944
wclavin@caltech.edu

Astronomers find evidence for the tightest-knit supermassive black hole duo observed to date.

Locked in an epic cosmic waltz 9 billion light years away, two supermassive black holes appear to be orbiting around each other every two years. The two giant bodies each have masses that are hundreds of millions of times larger than that of our sun, and the objects are separated by a distance roughly 50 times that which separates our sun and Pluto. When the pair merge in roughly 10,000 years, the titanic collision is expected to shake space and time itself, sending gravitational waves across the universe.

A Caltech-led team of astronomers has discovered evidence for this scenario taking place within a fiercely energetic object known as a quasar. Quasars are active cores of galaxies in which a supermassive black hole is siphoning material from a disk encircling it. In some quasars, the supermassive black hole creates a jet that shoots out at near the speed of light. The quasar observed in the new study PKS 2131-021, belongs to a subclass of quasars called blazars in which the jet is pointing toward the Earth. Astronomers already knew quasars could possess two orbiting supermassive black holes, but finding direct evidence for this has proved difficult.

Reporting in The Astrophysical Journal Letters, the researchers argue that PKS 2131-021 is now the second known candidate for a pair of supermassive black holes caught in the act of merging. The first candidate pair, within a quasar called OJ 287, orbit each other at greater distances, circling every nine years versus the two years it takes for the PKS 2131-021 pair to complete an orbit.

The telltale evidence came from radio observations of PKS 2131-021 that span 45 years. According to the study, a powerful jet emanating from one of the two black holes within PKS 2131-021 is shifting back and forth due to the pair’s orbital motion. This causes periodic changes in the quasar’s radio-light brightness. Five different observatories registered these oscillations, including Caltech’s Owens Valley Radio Observatory (OVRO), the University of Michigan Radio Astronomy Observatory (UMRAO) [no image available], MIT’s Haystack Observatory, the National Radio Astronomy Observatory (NRAO), Metsähovi Radio Observatory in Finland, and NASA’s Wide-field Infrared Survey Explorer (WISE) space satellite.

California Institute of Technology(US) Owens Valley Radio Observatory, Owens Valley, California, Altitude 1,222 m (4,009 ft).

Massachusettes Institute of Technology-Haystack Observatory(US) Westford, Massachusetts, USA, Altitude 131 m (430 ft).

National Radio Astronomy Observatory(US) Very Long Baseline Array.

Metsähovi Radio Observatory in Finland.

National Aeronautics and Space Administration(US) Wise/NEOWISE Telescope.

The combination of the radio data yields a nearly perfect sinusoidal light curve unlike anything observed from quasars before.

“When we realized that the peaks and troughs of the light curve detected from recent times matched the peaks and troughs observed between 1975 and 1983, we knew something very special was going on,” says Sandra O’Neill, lead author of the new study and an undergraduate student at Caltech who is mentored by Tony Readhead, Robinson Professor of Astronomy, Emeritus.

Tightest-Knit Supermassive Black Hole Duo Found in Heart of Distant Galaxy.

Ripples in Space and Time

Most, if not all, galaxies possess monstrous black holes at their cores, including our own Milky Way galaxy. When galaxies merge, their black holes “sink” to the middle of the newly formed galaxy and eventually join together to form an even more massive black hole.

Artist’s by now iconic conception of two merging black holes similar to those detected by LIGO. Credit: Aurore Simonnet /Caltech MIT Advanced aLIGO(US)/Sonoma State University (US).

As the black holes spiral toward each other, they increasingly disturb the fabric of space and time, sending out gravitational waves, which were first predicted by Albert Einstein more than 100 years ago.

The National Science Foundation’s LIGO (Laser Interferometer Gravitational-Wave Observatory), which is managed jointly by Caltech and MIT, detects gravitational waves from pairs of black holes up to dozens of times the mass of our sun. However, the supermassive black holes at the centers of galaxies have millions to billions of times as much mass as our sun, and give off lower frequencies of gravitational waves than those detected by LIGO.

Caltech /MIT Advanced aLigo

In the future, pulsar timing arrays—which consist of an array of pulsing dead stars precisely monitored by radio telescopes—should be able to detect the gravitational waves from supermassive black holes of this heft.

Gravity is talking. Lisa will listen. Dialogos of Eide.

The European Space Agency [La Agencia Espacial Europea] [Agence spatiale européenne][Europäische Weltraumorganisation](EU)National Aeronautics and Space Administration (US) eLISA space based, the future of gravitational wave research., due to launch in 2037.

(The upcoming Laser Interferometer Space Antenna, or LISA, mission would detect merging black holes whose masses are 1,000 to 10 million times greater than the mass of our sun.) So far, no gravitational waves have been registered from any of these heavier sources, but PKS 2131-021 provides the most promising target yet.

In the meantime, light waves are the best option to detect coalescing supermassive black holes.

The first such candidate, OJ 287, also exhibits periodic radio-light variations. These fluctuations are more irregular, and not sinusoidal, but they suggest the black holes orbit each other every nine years. The black holes within the new quasar, PKS 2131-021, orbit each other every two years and are 2,000 astronomical units apart, about 50 times the distance between our sun and Pluto, or 10 to 100 times closer than the pair in OJ 287. (An astronomical unit is the distance between Earth and the sun.)
===
Revealing the 45-Year Light Curve

Readhead says the discoveries unfolded like a “good detective novel,” beginning in 2008 when he and colleagues began using the 40-meter telescope at OVRO to study how black holes convert material they “feed” on into relativistic jets, or jets traveling at speeds up to 99.98 percent that of light. They had been monitoring the brightness of more than 1,000 blazars for this purpose when, in 2020, they noticed a unique case.

“PKS 2131 was varying not just periodically, but sinusoidally,” Readhead says. “That means that there is a pattern we can trace continuously over time.” The question, he says, then became how long has this sine wave pattern been going on?

The research team then went through archival radio data to look for past peaks in the light curves that matched predictions based on the more recent OVRO observations. First, data from NRAO’s Very Long Baseline Array and UMRAO revealed a peak from 2005 that matched predictions. The UMRAO data further showed there was no sinusoidal signal at all for 20 years before that time—until as far back as 1981 when another predicted peak was observed.

“The story would have stopped there, as we didn’t realize there were data on this object before 1980,” Readhead says. “But then Sandra picked up this project in June of 2021. If it weren’t for her, this beautiful finding would be sitting on the shelf.”

O’Neill began working with Readhead and the study’s second author Sebastian Kiehlmann, a postdoc at the University of Crete and former staff scientist at Caltech, as part of Caltech’s Summer Undergraduate Research Fellowship (SURF) program. O’Neill began college as a chemistry major but picked up the astronomy project because she wanted to stay active during the pandemic. “I came to realize I was much more excited about this than anything else I had worked on,” she says.

With the project back on the table, Readhead searched through the literature and found that the Haystack Observatory had made radio observations of PKS 2131-021 between 1975 and 1983. These data revealed another peak matching their predictions, this time occurring in 1976.

“This work shows the value of doing accurate monitoring of these sources over many years for performing discovery science,” says co-author Roger Blandford, Moore Distinguished Scholar in Theoretical Astrophysics at Caltech who is currently on sabbatical from Stanford University.

Like Clockwork

Readhead compares the system of the jet moving back and forth to a ticking clock, where each cycle, or period, of the sine wave corresponds to the two-year orbit of the black holes (though the observed cycle is actually five years due to light being stretched by the expansion of the universe). This ticking was first seen in 1976 and it continued for eight years before disappearing for 20 years, likely due to changes in the fueling of the black hole. The ticking has now been back for 17 years.

“The clock kept ticking,” he says, “The stability of the period over this 20-year gap strongly suggests that this blazar harbors not one supermassive black hole, but two supermassive black holes orbiting each other.”

The physics underlying the sinusoidal variations were at first a mystery, but Blandford came up with a simple and elegant model to explain the sinusoidal shape of the variations.

“We knew this beautiful sine wave had to be telling us something important about the system,” Readhead says. “Roger’s model shows us that it is simply the orbital motion that does this. Before Roger worked it out, nobody had figured out that a binary with a relativistic jet would have a light curve that looked like this.”

Says Kiehlmann: “Our study provides a blueprint for how to search for such blazar binaries in the future.”

See the full article here .

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

Please help promote STEM in your local schools.

Stem Education Coalition

Caltech campus

The The California Institute of Technology (US) is a private research university in Pasadena, California. The university is known for its strength in science and engineering, and is one among a small group of institutes of technology in the United States which is primarily devoted to the instruction of pure and applied sciences.

The California Institute of Technology was founded as a preparatory and vocational school by Amos G. Throop in 1891 and began attracting influential scientists such as George Ellery Hale, Arthur Amos Noyes, and Robert Andrews Millikan in the early 20th century. The vocational and preparatory schools were disbanded and spun off in 1910 and the college assumed its present name in 1920. In 1934, The California Institute of Technology was elected to the Association of American Universities, and the antecedents of National Aeronautics and Space Administration (US)’s Jet Propulsion Laboratory, which The California Institute of Technology continues to manage and operate, were established between 1936 and 1943 under Theodore von Kármán.

The California Institute of Technology has six academic divisions with strong emphasis on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. First-year students are required to live on campus, and 95% of undergraduates remain in the on-campus House System at The California Institute of Technology. Although The California Institute of Technology has a strong tradition of practical jokes and pranks, student life is governed by an honor code which allows faculty to assign take-home examinations. The The California Institute of Technology Beavers compete in 13 intercollegiate sports in the NCAA Division III’s Southern California Intercollegiate Athletic Conference (SCIAC).

As of October 2020, there are 76 Nobel laureates who have been affiliated with The California Institute of Technology, including 40 alumni and faculty members (41 prizes, with chemist Linus Pauling being the only individual in history to win two unshared prizes). In addition, 4 Fields Medalists and 6 Turing Award winners have been affiliated with The California Institute of Technology. There are 8 Crafoord Laureates and 56 non-emeritus faculty members (as well as many emeritus faculty members) who have been elected to one of the United States National Academies. Four Chief Scientists of the U.S. Air Force and 71 have won the United States National Medal of Science or Technology. Numerous faculty members are associated with the Howard Hughes Medical Institute(US) as well as National Aeronautics and Space Administration(US). According to a 2015 Pomona College(US) study, The California Institute of Technology ranked number one in the U.S. for the percentage of its graduates who go on to earn a PhD.

Research

The California Institute of Technology is classified among “R1: Doctoral Universities – Very High Research Activity”. Caltech was elected to The Association of American Universities in 1934 and remains a research university with “very high” research activity, primarily in STEM fields. The largest federal agencies contributing to research are National Aeronautics and Space Administration(US); National Science Foundation(US); Department of Health and Human Services(US); Department of Defense(US), and Department of Energy(US).

In 2005, The California Institute of Technology had 739,000 square feet (68,700 m^2) dedicated to research: 330,000 square feet (30,700 m^2) to physical sciences, 163,000 square feet (15,100 m^2) to engineering, and 160,000 square feet (14,900 m^2) to biological sciences.

In addition to managing NASA-JPL/Caltech (US), The California Institute of Technology also operates the Caltech Palomar Observatory(US); the Owens Valley Radio Observatory(US);the Caltech Submillimeter Observatory(US); the W. M. Keck Observatory at the Mauna Kea Observatory(US); the Laser Interferometer Gravitational-Wave Observatory at Livingston, Louisiana and Richland, Washington; and Kerckhoff Marine Laboratory(US) in Corona del Mar, California. The Institute launched the Kavli Nanoscience Institute at The California Institute of Technology in 2006; the Keck Institute for Space Studies in 2008; and is also the current home for the Einstein Papers Project. The Spitzer Science Center(US), part of the Infrared Processing and Analysis Center(US) located on The California Institute of Technology campus, is the data analysis and community support center for NASA’s Spitzer Infrared Space Telescope [no longer in service].

The California Institute of Technology partnered with University of California at Los Angeles(US) to establish a Joint Center for Translational Medicine (UCLA-Caltech JCTM), which conducts experimental research into clinical applications, including the diagnosis and treatment of diseases such as cancer.

The California Institute of Technology operates several Total Carbon Column Observing Network(US) stations as part of an international collaborative effort of measuring greenhouse gases globally. One station is on campus.

From The California Institute of Technology (US): “Chaining Atoms Together Yields Quantum Storage”

From The California Institute of Technology (US)

February 16, 2022
Robert Perkins

New technique could make quantum networking possible.

Engineers at Caltech have developed an approach for quantum storage could help pave the way for the development of large-scale optical quantum networks.

Artist’s illustration depicts the quantum spin of an ytterbium ion with the surrounding yttrium orthovanadate crystal. The spin states of the atoms can be used as a processing unit (like transistors on a computer chip). By using the ytterbium to control four vanadium atoms simultaneously, the engineers were able to realize a 2-qubit processor, an important building block in the development of quantum computers and quantum networks. Credit: MAAYAN VISUALS.

The new system relies on nuclear spins—the angular momentum of an atom’s nucleus—oscillating collectively as a spin wave. This collective oscillation effectively chains up several atoms to store information.

The work, which is described in a paper published on February 16 in the journal Nature, utilizes a quantum bit (or qubit) made from an ion of ytterbium (Yb), a rare earth element also used in lasers. The team, led by Andrei Faraon (BS ’04), professor of applied physics and electrical engineering, embedded the ion in a transparent crystal of yttrium orthovanadate (YVO4) and manipulated its quantum states via a combination of optical and microwave fields. The team then used the Yb qubit to control the nuclear spin states of multiple surrounding vanadium atoms in the crystal.

“Based on our previous work, single ytterbium ions were known to be excellent candidates for optical quantum networks, but we needed to link them with additional atoms. We demonstrate that in this work,” says Faraon, the co-corresponding author of the Nature paper.

The device was fabricated at the Kavli Nanoscience Institute at Caltech, and then tested at very low temperatures in Faraon’s lab.

A new technique to utilize entangled nuclear spins as a quantum memory was inspired by methods used in nuclear magnetic resonance (NMR).

“To store quantum information in nuclear spins, we developed new techniques similar to those employed in NMR machines used in hospitals,” says Joonhee Choi, a postdoctoral fellow at Caltech and co-corresponding author of the paper. “The main challenge was to adapt existing techniques to work in the absence of a magnetic field.”

A unique feature of this system is the pre-determined placement of vanadium atoms around the ytterbium qubit as prescribed by the crystal lattice. Every qubit the team measured had an identical memory register, meaning it would store the same information.

“The ability to build a technology reproducibly and reliably is key to its success,” says graduate student Andrei Ruskuc, first author of the paper. “In the scientific context, this let us gain unprecedented insight into microscopic interactions between ytterbium qubits and the vanadium atoms in their environment.”

This research is part of a broader effort by Faraon’s lab to lay the foundation for future quantum networks.

Quantum networks would connect quantum computers through a system that operates at a quantum, rather than classical, level. In theory, quantum computers w one day be able to perform certain functions faster than classical computers by taking advantage of the special properties of quantum mechanics, including superposition, which allows quantum bits to store information as a 1 and a 0 simultaneously.

As they can with classical computers, engineers would like to be able to connect multiple quantum computers to share data and work together—creating a “quantum internet.” This would open the door to several applications, including the ability to solve computations that are too large to be handled by a single quantum computer, as well as the establishment of unbreakably secure communications using quantum cryptography.

This research was funded by the Institute of Quantum Information and Matter (IQIM), a National Science Foundation Physics Frontiers Center, with support from the Gordon and Betty Moore Foundation, the Office of Naval Research, the Air Force Office of Scientific Research, Northrop Grumman, General Atomics, and the Weston Havens Foundation.

See the full article here .

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

Please help promote STEM in your local schools.

Stem Education Coalition

Caltech campus

The The California Institute of Technology (US) is a private research university in Pasadena, California. The university is known for its strength in science and engineering, and is one among a small group of institutes of technology in the United States which is primarily devoted to the instruction of pure and applied sciences.

The California Institute of Technology was founded as a preparatory and vocational school by Amos G. Throop in 1891 and began attracting influential scientists such as George Ellery Hale, Arthur Amos Noyes, and Robert Andrews Millikan in the early 20th century. The vocational and preparatory schools were disbanded and spun off in 1910 and the college assumed its present name in 1920. In 1934, The California Institute of Technology was elected to the Association of American Universities, and the antecedents of National Aeronautics and Space Administration (US)’s Jet Propulsion Laboratory, which The California Institute of Technology continues to manage and operate, were established between 1936 and 1943 under Theodore von Kármán.

The California Institute of Technology has six academic divisions with strong emphasis on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. First-year students are required to live on campus, and 95% of undergraduates remain in the on-campus House System at The California Institute of Technology. Although The California Institute of Technology has a strong tradition of practical jokes and pranks, student life is governed by an honor code which allows faculty to assign take-home examinations. The The California Institute of Technology Beavers compete in 13 intercollegiate sports in the NCAA Division III’s Southern California Intercollegiate Athletic Conference (SCIAC).

As of October 2020, there are 76 Nobel laureates who have been affiliated with The California Institute of Technology, including 40 alumni and faculty members (41 prizes, with chemist Linus Pauling being the only individual in history to win two unshared prizes). In addition, 4 Fields Medalists and 6 Turing Award winners have been affiliated with The California Institute of Technology. There are 8 Crafoord Laureates and 56 non-emeritus faculty members (as well as many emeritus faculty members) who have been elected to one of the United States National Academies. Four Chief Scientists of the U.S. Air Force and 71 have won the United States National Medal of Science or Technology. Numerous faculty members are associated with the Howard Hughes Medical Institute(US) as well as National Aeronautics and Space Administration(US). According to a 2015 Pomona College(US) study, The California Institute of Technology ranked number one in the U.S. for the percentage of its graduates who go on to earn a PhD.

Research

The California Institute of Technology is classified among “R1: Doctoral Universities – Very High Research Activity”. Caltech was elected to The Association of American Universities in 1934 and remains a research university with “very high” research activity, primarily in STEM fields. The largest federal agencies contributing to research are National Aeronautics and Space Administration(US); National Science Foundation(US); Department of Health and Human Services(US); Department of Defense(US), and Department of Energy(US).

In 2005, The California Institute of Technology had 739,000 square feet (68,700 m^2) dedicated to research: 330,000 square feet (30,700 m^2) to physical sciences, 163,000 square feet (15,100 m^2) to engineering, and 160,000 square feet (14,900 m^2) to biological sciences.

In addition to managing NASA-JPL/Caltech (US), The California Institute of Technology also operates the Caltech Palomar Observatory(US); the Owens Valley Radio Observatory(US);the Caltech Submillimeter Observatory(US); the W. M. Keck Observatory at the Mauna Kea Observatory(US); the Laser Interferometer Gravitational-Wave Observatory at Livingston, Louisiana and Richland, Washington; and Kerckhoff Marine Laboratory(US) in Corona del Mar, California. The Institute launched the Kavli Nanoscience Institute at The California Institute of Technology in 2006; the Keck Institute for Space Studies in 2008; and is also the current home for the Einstein Papers Project. The Spitzer Science Center(US), part of the Infrared Processing and Analysis Center(US) located on The California Institute of Technology campus, is the data analysis and community support center for NASA’s Spitzer Infrared Space Telescope [no longer in service].

The California Institute of Technology partnered with University of California at Los Angeles(US) to establish a Joint Center for Translational Medicine (UCLA-Caltech JCTM), which conducts experimental research into clinical applications, including the diagnosis and treatment of diseases such as cancer.

The California Institute of Technology operates several Total Carbon Column Observing Network(US) stations as part of an international collaborative effort of measuring greenhouse gases globally. One station is on campus.

From The California Institute of Technology (US): “Palomar Survey Instrument Analyzes Impact of Starlink Satellites”

From The California Institute of Technology (US)

January 17, 2022
Whitney Clavin
(626) 395‑1944
wclavin@caltech.edu

A study of archival images from Zwicky Transient Facility shows an increase in satellite streaks.

The streak from a Starlink satellite appears in this image of the Andromeda galaxy, taken by The Zwicky Transient Facility, or ZTF, during twilight on May 19, 2021. The image shows only one-sixteenth of ZTF’s full field of view. Credit: Caltech Optical Observatories/The Caltech NASA Infrared Processing and Analysis Center(US).

Since 2019, SpaceX has been launching an increasing number of internet satellites into orbit around Earth. The satellite constellation, called Starlink, now includes nearly 1,800 members orbiting at altitudes of about 550 kilometers. Astronomers have expressed concerns that that these objects, which can appear as streaks in telescope images, could hamper their scientific observations.

To quantify these effects, a team of researchers studied archival images captured by the National Science Foundation (NSF)-funded Zwicky Transient Facility (ZTF), an instrument that operates from Caltech’s Palomar Observatory near San Diego.

Zwicky Transient Facility (ZTF) instrument installed on the 1.2m diameter Samuel Oschin Telescope at Palomar Observatory in California. Credit: Caltech Optical Observatories.

Caltech Palomar Samuel Oschin 48 inch Telescope, located in San Diego County, California, U.S.A., altitude 1,712 m (5,617 ft). Credit: Caltech.

ZTF scans the entire night sky every two days, cataloguing cosmic objects that explode, blink, or otherwise change over time. This includes everything from supernovae to near-Earth asteroids. The Zwicky team members say they decided to specifically study the effects of Starlink satellites because they currently represent the largest low-Earth orbit, or LEO, constellation, and they have well-characterized orbits.

The findings, reported in the January 17 issue of The Astrophysical Journal Letters, shows 5301 satellite streaks appear in archival images taken between November 2019 and September 2021. The streaks are most apparent in so-called twilight observations-those taken at dawn or dusk-which are important for finding near-Earth asteroids that appear close to the sun in the sky. ZTF has discovered several asteroids of this nature, including 2020 AV2, the first asteroid spotted with an orbit that fits entirely within the orbit of Venus.

“In 2019 0.5 percent of twilight images were affected, and now almost 20 percent are affected,” says Przemek Mróz, study lead author and a former Caltech postdoctoral scholar who is now at The University of Warsaw [Uniwersytet Warszawski](PL).

In the future, the scientists expect that nearly all of the ZTF images taken during twilight will contain at least one streak, especially after the Starlink constellation reaches 10,000 satellites, a goal SpaceX hopes to reach by 2027.

“We don’t expect Starlink satellites to affect non-twilight images, but if the satellite constellation of other companies goes into higher orbits, this could cause problems for non-twilight observations,” Mróz says.

Yet despite the increase in image streaks, the new report notes that ZTF science operations have not been strongly affected. Study co-author Tom Prince, the Ira S. Bowen Professor of Physics, Emeritus, at Caltech, says the paper shows a single streak affects less than one-tenth of a percent of the pixels in a ZTF image.

“There is a small chance that we would miss an asteroid or another event hidden behind a satellite streak, but compared to the impact of weather, such as a cloudy sky, these are rather small effects for ZTF.”

Prince says that software can be developed to help mitigate potential problems; for example, software could predict the locations of the Starlink satellites and thus help astronomers avoid scheduling an observation when one might be in the field of view. Software can also assess whether a passing satellite may have affected an astronomical observation, which would allow astronomers to mask or otherwise reduce the negative effects of the streaks.

The new study also looked at the effectiveness of visors on the Starlink satellites, which SpaceX added beginning in 2020 to block sunlight from reaching the spacecraft. According to the ZTF observations, the visors reduce the satellite brightness by a factor of about five. That dims the satellites down to an apparent brightness level of 6.8 magnitude (the brightest stars are first magnitude, and the faintest stars we can see with our eyes are about sixth magnitude).

This is still not dim enough to meet standards outlined by the Satellite Constellations 1 (SATCON1) workshop in 2020, a gathering sponsored by The NSF NOIRLab [National Optical-Infrared Astronomy Research Laboratory](US) and The American Astronomical Society (US) to bring together astronomers, policymakers, and other experts to discuss the impact of large satellite constellations on astronomy and society. The group called for all LEO satellites to be at seventh magnitude or fainter.

The study authors also note their study is specific to ZTF. Like ZTF, the upcoming Vera C. Rubin Observatory, under construction in Chile, will also survey the sky nightly, but due to its more sensitive imager, astronomers predict that it may be more negatively affected by satellite streaks than ZTF.

Other authors of the study include Richard Dekany (BS ’89), Matthew Graham, Steven Groom, and Frank Masci of Caltech; Dmitry Duev, a former Caltech postdoc now at Weights & Biases Inc.; Angel Otarola of The European Southern Observatory [Observatoire européen austral][Europaiche Sûdsternwarte] (EU)(CL); and Michael S. Medford of The University of California-Berkeley (US) and DOE’s Lawrence Berkeley National Laboratory (US).

ZTF is funded by The National Science Foundation(US) and an international collaboration of partners. Additional support comes from The Heising-Simons Foundation (US) and Caltech. ZTF data are processed and archived by Caltech NASA Infrared Science Archive IPAC. NASA supports ZTF’s search for near-Earth objects through the Near-Earth Object Observations program.

See the full article here .

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

Please help promote STEM in your local schools.

Stem Education Coalition

Caltech campus

The The California Institute of Technology (US) is a private research university in Pasadena, California. The university is known for its strength in science and engineering, and is one among a small group of institutes of technology in the United States which is primarily devoted to the instruction of pure and applied sciences.

The California Institute of Technology was founded as a preparatory and vocational school by Amos G. Throop in 1891 and began attracting influential scientists such as George Ellery Hale, Arthur Amos Noyes, and Robert Andrews Millikan in the early 20th century. The vocational and preparatory schools were disbanded and spun off in 1910 and the college assumed its present name in 1920. In 1934, The California Institute of Technology was elected to the Association of American Universities, and the antecedents of National Aeronautics and Space Administration (US)’s Jet Propulsion Laboratory, which The California Institute of Technology continues to manage and operate, were established between 1936 and 1943 under Theodore von Kármán.

The California Institute of Technology has six academic divisions with strong emphasis on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. First-year students are required to live on campus, and 95% of undergraduates remain in the on-campus House System at The California Institute of Technology. Although The California Institute of Technology has a strong tradition of practical jokes and pranks, student life is governed by an honor code which allows faculty to assign take-home examinations. The The California Institute of Technology Beavers compete in 13 intercollegiate sports in the NCAA Division III’s Southern California Intercollegiate Athletic Conference (SCIAC).

As of October 2020, there are 76 Nobel laureates who have been affiliated with The California Institute of Technology, including 40 alumni and faculty members (41 prizes, with chemist Linus Pauling being the only individual in history to win two unshared prizes). In addition, 4 Fields Medalists and 6 Turing Award winners have been affiliated with The California Institute of Technology. There are 8 Crafoord Laureates and 56 non-emeritus faculty members (as well as many emeritus faculty members) who have been elected to one of the United States National Academies. Four Chief Scientists of the U.S. Air Force and 71 have won the United States National Medal of Science or Technology. Numerous faculty members are associated with the Howard Hughes Medical Institute(US) as well as National Aeronautics and Space Administration(US). According to a 2015 Pomona College(US) study, The California Institute of Technology ranked number one in the U.S. for the percentage of its graduates who go on to earn a PhD.

Research

The California Institute of Technology is classified among “R1: Doctoral Universities – Very High Research Activity”. Caltech was elected to The Association of American Universities in 1934 and remains a research university with “very high” research activity, primarily in STEM fields. The largest federal agencies contributing to research are National Aeronautics and Space Administration(US); National Science Foundation(US); Department of Health and Human Services(US); Department of Defense(US), and Department of Energy(US).

In 2005, The California Institute of Technology had 739,000 square feet (68,700 m^2) dedicated to research: 330,000 square feet (30,700 m^2) to physical sciences, 163,000 square feet (15,100 m^2) to engineering, and 160,000 square feet (14,900 m^2) to biological sciences.

In addition to managing NASA-JPL/Caltech (US), The California Institute of Technology also operates the Caltech Palomar Observatory(US); the Owens Valley Radio Observatory(US);the Caltech Submillimeter Observatory(US); the W. M. Keck Observatory at the Mauna Kea Observatory(US); the Laser Interferometer Gravitational-Wave Observatory at Livingston, Louisiana and Richland, Washington; and Kerckhoff Marine Laboratory(US) in Corona del Mar, California. The Institute launched the Kavli Nanoscience Institute at The California Institute of Technology in 2006; the Keck Institute for Space Studies in 2008; and is also the current home for the Einstein Papers Project. The Spitzer Science Center(US), part of the Infrared Processing and Analysis Center(US) located on The California Institute of Technology campus, is the data analysis and community support center for NASA’s Spitzer Infrared Space Telescope [no longer in service].

The California Institute of Technology partnered with University of California at Los Angeles(US) to establish a Joint Center for Translational Medicine (UCLA-Caltech JCTM), which conducts experimental research into clinical applications, including the diagnosis and treatment of diseases such as cancer.

The California Institute of Technology operates several Total Carbon Column Observing Network(US) stations as part of an international collaborative effort of measuring greenhouse gases globally. One station is on campus.

From The California Institute of Technology (US) via phys.org : “Persistent radio source QRS121102 investigated in detail”

From The California Institute of Technology (US)

via

phys.org

January 11, 2022
Tomasz Nowakowski

VLA images (in J2000 coordinates) of QRS121102 in seven epochs, with band indicated in parentheses. Credit: Ge Chen et al., 2022.

National Radio Astronomy Observatory(US)Karl G Jansky Very Large Array located in central New Mexico on the Plains of San Agustin, between the towns of Magdalena and Datil, ~50 miles (80 km) west of Socorro. The VLA comprises twenty-eight 25-meter radio telescopes.

Astronomers from the California Institute of Technology (Caltech) have investigated a persistent radio source known as QRS121102 that is associated with the fast radio burst FRB 121102. Results of the study, published January 4 in The Astrophysical Journal, shed more light on the origin of this source and could help us better understand the nature of fast radio bursts.

Fast radio bursts (FRBs) are intense bursts of radio emission lasting milliseconds and showcasing characteristic dispersion sweep of radio pulsars. The physical nature of these bursts is yet unknown, and astronomers consider a variety of explanations ranging from synchrotron maser emission from young magnetars in supernova remnants to cosmic string cusps.

FRB 121102 is the first repeating fast radio burst detected and one of the most extensively studied FRB sources. It exhibits complex burst morphology, sub-burst downward frequency drifts, and also complex pulse phenomenology. FRB 121102 is also one of only two FRBs reported to be spatially associated with persistent radio emission of unknown origin.

A team of astronomers led by Caltech’s Ge Chen took a closer look at this persistent radio source. For this purpose, they observed QRS121102 with the G. Jansky Very Large Array (VLA)[above] and the Low-Resolution Imaging Spectrometer (LRIS) at the Keck Observatory.

UCO Keck LRIS on Keck 1.

W.M. Keck Observatory two ten meter telescopes operated by California Institute of Technology(US) and The University of California(US), at Mauna Kea Observatory, Hawaii USA, altitude 4,207 m (13,802 ft). Credit: Caltech.

“In this work, we investigated the origin of the persistent radio source, QRS121102, associated with FRB 121102. We present new VLA monitoring data (12 to 26 GHz) and new spectra from Keck/LRIS,” the researchers wrote in the paper.

The observations allowed the team to estimate the physical size of QRS121102. It was found that the emission radius is most likely between 0.1 and 1 light year. Such a relatively small size suggests a few compact radio source candidates, for instance, active galactic nuclei (AGN), pulsar wind nebulae (PWNe), very young supernova remnants (SNRs) and gamma-ray burst (GRB) afterglows.

Given that QRS121102 may be an AGN, the astronomers constrained the mass of the potential black hole. They found that this mass would be lower than 100,000 solar masses, which does not support the AGN scenario as this source is too faint in the X-ray for its calculated low black hole mass and bright radio emission.

The radio luminosity of QRS121102, from 400 MHz to 10 GHz, was measured to be approximately 20 billion TW/Hz. Therefore, according to the researchers, this source is too luminous to be an SNR. It was added that QRS121102 is also too bright to be a long-duration GRB (LGRB) radio afterglow.

Summing up the results, the researchers noted that it is too early to draw final conclusions regarding the true origin of QRS121102 and further observations are required in order to get more insights into the nature of this source.

“We urge continued broadband radio monitoring of QRS121102 to search for long-term evolution, and the detailed evaluation of potential analogs that may provide greater insight into the nature of this remarkable, mysterious class of object,” the authors of the paper concluded.

See the full article here .

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

Please help promote STEM in your local schools.

Stem Education Coalition

Caltech campus

The The California Institute of Technology (US) is a private research university in Pasadena, California. The university is known for its strength in science and engineering, and is one among a small group of institutes of technology in the United States which is primarily devoted to the instruction of pure and applied sciences.

The California Institute of Technology was founded as a preparatory and vocational school by Amos G. Throop in 1891 and began attracting influential scientists such as George Ellery Hale, Arthur Amos Noyes, and Robert Andrews Millikan in the early 20th century. The vocational and preparatory schools were disbanded and spun off in 1910 and the college assumed its present name in 1920. In 1934, The California Institute of Technology was elected to the Association of American Universities, and the antecedents of National Aeronautics and Space Administration (US)’s Jet Propulsion Laboratory, which The California Institute of Technology continues to manage and operate, were established between 1936 and 1943 under Theodore von Kármán.

The California Institute of Technology has six academic divisions with strong emphasis on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. First-year students are required to live on campus, and 95% of undergraduates remain in the on-campus House System at The California Institute of Technology. Although The California Institute of Technology has a strong tradition of practical jokes and pranks, student life is governed by an honor code which allows faculty to assign take-home examinations. The The California Institute of Technology Beavers compete in 13 intercollegiate sports in the NCAA Division III’s Southern California Intercollegiate Athletic Conference (SCIAC).

As of October 2020, there are 76 Nobel laureates who have been affiliated with The California Institute of Technology, including 40 alumni and faculty members (41 prizes, with chemist Linus Pauling being the only individual in history to win two unshared prizes). In addition, 4 Fields Medalists and 6 Turing Award winners have been affiliated with The California Institute of Technology. There are 8 Crafoord Laureates and 56 non-emeritus faculty members (as well as many emeritus faculty members) who have been elected to one of the United States National Academies. Four Chief Scientists of the U.S. Air Force and 71 have won the United States National Medal of Science or Technology. Numerous faculty members are associated with the Howard Hughes Medical Institute(US) as well as National Aeronautics and Space Administration(US). According to a 2015 Pomona College(US) study, The California Institute of Technology ranked number one in the U.S. for the percentage of its graduates who go on to earn a PhD.

Research

The California Institute of Technology is classified among “R1: Doctoral Universities – Very High Research Activity”. Caltech was elected to The Association of American Universities in 1934 and remains a research university with “very high” research activity, primarily in STEM fields. The largest federal agencies contributing to research are National Aeronautics and Space Administration(US); National Science Foundation(US); Department of Health and Human Services(US); Department of Defense(US), and Department of Energy(US).

In 2005, The California Institute of Technology had 739,000 square feet (68,700 m^2) dedicated to research: 330,000 square feet (30,700 m^2) to physical sciences, 163,000 square feet (15,100 m^2) to engineering, and 160,000 square feet (14,900 m^2) to biological sciences.

In addition to managing NASA-JPL/Caltech (US), The California Institute of Technology also operates the Caltech Palomar Observatory(US); the Owens Valley Radio Observatory(US);the Caltech Submillimeter Observatory(US); the W. M. Keck Observatory at the Mauna Kea Observatory(US); the Laser Interferometer Gravitational-Wave Observatory at Livingston, Louisiana and Richland, Washington; and Kerckhoff Marine Laboratory(US) in Corona del Mar, California. The Institute launched the Kavli Nanoscience Institute at The California Institute of Technology in 2006; the Keck Institute for Space Studies in 2008; and is also the current home for the Einstein Papers Project. The Spitzer Science Center(US), part of the Infrared Processing and Analysis Center(US) located on The California Institute of Technology campus, is the data analysis and community support center for NASA’s Spitzer Infrared Space Telescope [no longer in service].

The California Institute of Technology partnered with University of California at Los Angeles(US) to establish a Joint Center for Translational Medicine (UCLA-Caltech JCTM), which conducts experimental research into clinical applications, including the diagnosis and treatment of diseases such as cancer.

The California Institute of Technology operates several Total Carbon Column Observing Network(US) stations as part of an international collaborative effort of measuring greenhouse gases globally. One station is on campus.

From The California Institute of Technology (US) : “Black Hole Devours a Star Decades Ago – Goes Unnoticed Until Now”

From The California Institute of Technology (US)

January 10, 2022

Whitney Clavin
(626) 395‑1944
wclavin@caltech.edu

Artist’s conception of a tidal disruption event (TDE), a star being shredded by the powerful gravity of a supermassive black hole. Material from the star spirals into a disk rotating around the black hole, and a jet of particles is ejected. Credit: Sophia Dagnello, The National Radio Astronomy Observatory(US)/The Associated Universities Inc (US)/The National Science Foundation (US).

Every galaxy, including our own Milky Way, has at its center a massive black hole whose gravity influences the stars around it.

SGR A* Credit: Pennsylvania State University(US) and National Aeronautics Space Agency(US) Chandra X-ray Observatory (US).

The National Aeronautics and Space Administration Chandra X-ray telescope(US).

Sgr A* from ESO [Observatoire européen austral][Europäische Südsternwarte] (EU) (CL) VLT.

European Southern Observatory(EU) , Very Large Telescope at Cerro Paranal in the Atacama Desert •ANTU (UT1; The Sun ) •KUEYEN (UT2; The Moon ) •MELIPAL (UT3; The Southern Cross ), and •YEPUN (UT4; Venus – as evening star). Elevation 2,635 m (8,645 ft) from above Credit J.L. Dauvergne & G. Hüdepohl atacama photo.

Generally, the stars orbit around the black hole without incident, but sometimes a star will wander a little too close, and the black hole will “make a meal” of the star in a process astrophysicists have termed spaghettification.

“Gravity around the black hole will shred these unlucky stars, causing them to be squeezed into thin streams and fall into the black hole,” says Vikram Ravi, assistant professor of astronomy at Caltech. “This is a really messy process. The stars don’t go quietly!”

As the stars are devoured, their remains swirl around the black hole and glow with light of different frequencies, which telescopes can detect. In some cases, the stellar remains are expelled in powerful jets that shine with radio-frequency light waves.

Ravi and his team, including two graduate students at Caltech, have now discovered what appears to be one of these black-hole-eating-a-star events—also known as tidal disruption events, or TDEs—using archival observations made by radio telescopes. Of the roughly 100 TDEs that have been discovered to date, this is only the second candidate to be found using radio waves. The first was discovered in 2020 by Marin Anderson (MS ’14, PhD ’19), a postdoctoral scholar at NASA-JPL/Caltech (US), which is managed by Caltech for NASA.

“TDEs are primarily discovered in optical and X-ray light, but these methods may be missing some TDEs, such as those buried in dust,” says Ravi, who is lead author of a new report on the findings accepted for publication in The Astrophysical Journal. “This study demonstrates the power of radio surveys to discover TDEs.” Other Caltech authors include graduate student Dillon Dong (MS ’18), Professor of Astronomy Gregg Hallinan, and staff scientist Casey Law. Bryan Gaensler of University of Toronto is also an author.

The same newfound TDE was also uncovered by astronomers at The University of Toronto (CA), so the scientists teamed up to jointly publish their findings.

“An unprecedented amount of radio observations are now becoming available, positioning us to discover many more sources like this one,” says co-author Hannah Dykaar of the University of Toronto. “Interestingly, neither of the radio-discovered candidates were found in the type of galaxy most popular for TDEs. Finding more of these radio TDEs could help us to illuminate ongoing mysteries about what types of galaxies they occur in and just how many there are in the universe.”

The new TDE event, called J1533+2727, was first noticed by Ravi’s team after two high school interns from Cambridge, Massachusetts—Ginevra Zaccagnini and Jackson Codd— scanned through decades of radio data captured by the National Radio Astronomy Observatory’s (NRAO’s) Karl G. Jansky Very Large Array (VLA) in New Mexico.

National Radio Astronomy Observatory(US)Karl G Jansky Very Large Array located in central New Mexico on the Plains of San Agustin, between the towns of Magdalena and Datil, ~50 miles (80 km) west of Socorro. The VLA comprises twenty-eight 25-meter radio telescopes.

The students worked with Ravi from 2018 to 2019 while he was a postdoctoral fellow at Harvard University (US). By comparing radio observations taken years apart, they found that one object, J1533+2727, was fairly bright in the mid-1990s but had dramatically faded by 2017.

Like detectives uncovering new clues in a historical case, they then searched the archives of the NRAO’s Green Bank 300-foot telescope and learned that the same object was even brighter in 1986 and 1987 (the Green Bank telescope collapsed in 1988). Since its peak of brightness in the mid-1980s, J1533+2727 has faded by a factor of 500.

Adding up all the evidence, including brand-new VLA observations, the scientists think that the new TDE occurred when a supermassive black hole at the heart of a galaxy 500 million light-years away crushed a star and then expelled a radio jet traveling at near the speed of light. Three other TDEs have been associated with these so-called relativistic jets so far, but those were found in galaxies over 10 times farther away.

“This is the first discovery of a relativistic TDE candidate in the relatively nearby universe, showing that these radio-bright TDEs may be more common than we thought before,” says Ravi.

TDEs have become a valuable tool for studying massive black holes. They were first theorized in the 1980s and then finally detected for the first time in the 1990s. Now that more than 100 have been found, the events have become a new means to study the hidden happenings of black holes.

Caltech graduate student Jean Somalwar, a new member in Ravi’s group who is not an author on the current study, is hoping to capture more radio-bright TDEs with the VLA. She and her team have recently published one such candidate, which is either a TDE or a mysterious flare from an active supermassive black hole. Additionally, she is using data from the Zwicky Transient Facility, or ZTF, at Caltech’s Palomar Observatory to uncover more optically bright TDEs (ZTF, which scans the night sky every two nights in visible light, has already discovered more than 15 of these events).

Zwicky Transient Facility (ZTF) instrument installed on the 1.2m diameter Samuel Oschin Telescope at Palomar Observatory in California. Credit: Caltech Optical Observatories.

Caltech Palomar Samuel Oschin 48 inch Telescope, located in San Diego County, California, U.S.A., altitude 1,712 m (5,617 ft). Credit: Caltech.

“TDEs basically turn flashlights onto these extreme regions at the centers of galaxies that we would not otherwise be able to see,” says Somalwar. “They have become very powerful tools in recent years.”

Somalwar and Ravi presented these results virtually on January 10, 2022, at the 239th meeting of The American Astronomical Society(US).

“TDEs basically turn flashlights onto these extreme regions at the centers of galaxies that we would not otherwise be able to see,” says Somalwar. “They have become very powerful tools in recent years.”

Somalwar and Ravi presented these results virtually on January 10, 2022, at the 239th meeting of the American Astronomical Society.

See the full article here .

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

Please help promote STEM in your local schools.

Stem Education Coalition

Caltech campus

The The California Institute of Technology (US) is a private research university in Pasadena, California. The university is known for its strength in science and engineering, and is one among a small group of institutes of technology in the United States which is primarily devoted to the instruction of pure and applied sciences.

The California Institute of Technology was founded as a preparatory and vocational school by Amos G. Throop in 1891 and began attracting influential scientists such as George Ellery Hale, Arthur Amos Noyes, and Robert Andrews Millikan in the early 20th century. The vocational and preparatory schools were disbanded and spun off in 1910 and the college assumed its present name in 1920. In 1934, The California Institute of Technology was elected to the Association of American Universities, and the antecedents of National Aeronautics and Space Administration (US)’s Jet Propulsion Laboratory, which The California Institute of Technology continues to manage and operate, were established between 1936 and 1943 under Theodore von Kármán.

The California Institute of Technology has six academic divisions with strong emphasis on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. First-year students are required to live on campus, and 95% of undergraduates remain in the on-campus House System at The California Institute of Technology. Although The California Institute of Technology has a strong tradition of practical jokes and pranks, student life is governed by an honor code which allows faculty to assign take-home examinations. The The California Institute of Technology Beavers compete in 13 intercollegiate sports in the NCAA Division III’s Southern California Intercollegiate Athletic Conference (SCIAC).

As of October 2020, there are 76 Nobel laureates who have been affiliated with The California Institute of Technology, including 40 alumni and faculty members (41 prizes, with chemist Linus Pauling being the only individual in history to win two unshared prizes). In addition, 4 Fields Medalists and 6 Turing Award winners have been affiliated with The California Institute of Technology. There are 8 Crafoord Laureates and 56 non-emeritus faculty members (as well as many emeritus faculty members) who have been elected to one of the United States National Academies. Four Chief Scientists of the U.S. Air Force and 71 have won the United States National Medal of Science or Technology. Numerous faculty members are associated with the Howard Hughes Medical Institute(US) as well as National Aeronautics and Space Administration(US). According to a 2015 Pomona College(US) study, The California Institute of Technology ranked number one in the U.S. for the percentage of its graduates who go on to earn a PhD.

Research

The California Institute of Technology is classified among “R1: Doctoral Universities – Very High Research Activity”. Caltech was elected to The Association of American Universities in 1934 and remains a research university with “very high” research activity, primarily in STEM fields. The largest federal agencies contributing to research are National Aeronautics and Space Administration(US); National Science Foundation(US); Department of Health and Human Services(US); Department of Defense(US), and Department of Energy(US).

In 2005, The California Institute of Technology had 739,000 square feet (68,700 m^2) dedicated to research: 330,000 square feet (30,700 m^2) to physical sciences, 163,000 square feet (15,100 m^2) to engineering, and 160,000 square feet (14,900 m^2) to biological sciences.

In addition to managing NASA-JPL/Caltech (US), The California Institute of Technology also operates the Caltech Palomar Observatory(US); the Owens Valley Radio Observatory(US);the Caltech Submillimeter Observatory(US); the W. M. Keck Observatory at the Mauna Kea Observatory(US); the Laser Interferometer Gravitational-Wave Observatory at Livingston, Louisiana and Richland, Washington; and Kerckhoff Marine Laboratory(US) in Corona del Mar, California. The Institute launched the Kavli Nanoscience Institute at The California Institute of Technology in 2006; the Keck Institute for Space Studies in 2008; and is also the current home for the Einstein Papers Project. The Spitzer Science Center(US), part of the Infrared Processing and Analysis Center(US) located on The California Institute of Technology campus, is the data analysis and community support center for NASA’s Spitzer Infrared Space Telescope [no longer in service].

The California Institute of Technology partnered with University of California at Los Angeles(US) to establish a Joint Center for Translational Medicine (UCLA-Caltech JCTM), which conducts experimental research into clinical applications, including the diagnosis and treatment of diseases such as cancer.

The California Institute of Technology operates several Total Carbon Column Observing Network(US) stations as part of an international collaborative effort of measuring greenhouse gases globally. One station is on campus.

From The California Institute of Technology (US) : “Astronomers Find Most Luminous ‘Cow’ to Shine in X-Rays”

From The California Institute of Technology (US)

January 10, 2022

Whitney Clavin
(626) 395‑1944
wclavin@caltech.edu

Results narrow in on what powers new class of supernovae.

Artwork comparing a normal supernova to a Cow-like supernova. Credit: Bill Saxton, The National Radio Astronomy Observatory(US)/The Associated Universities Inc(US)/The National Science Foundation(US).

The location of AT2020mrf is seen here in images from the eROSITA X-ray telescope. The right panel shows the detection of a new source between July 21 and July 24, 2020. The left panel shows that the source was not there six months earlier.
Credit: Pavel Medvedev, eROSITA MPG Institute for Extraterrestrial Physics [MPG Institut für extraterrestrische Physik]( DE)

Another member of the new “Cow” class of supernova explosions has been discovered—the brightest one seen in X-rays to date. The new event, dubbed AT2020mrf, is only the fifth found so far belonging to the Cow class of supernovae. The group is named after the first supernova found in this class, AT2018cow, whose randomly generated name just happened to spell the word “cow.”

What lies behind these unusual stellar explosions? New evidence points to either active black holes or neutron stars.

When a massive star explodes, it leaves behind either a black hole or a dead stellar remnant called a neutron star. Typically, these stellar remnants are relatively inactive and shrouded by material ejected in the explosion. But according to Yuhan Yao (MS ’20), a graduate student at Caltech, Cow-like events have at their cores very active, and mostly exposed, compact objects that emit high-energy X-ray emission. Yao presented the new findings [The Astrophysical Journal] virtually at the 239th meeting of The American Astronomical Society (US).

Other authors include Yao’s advisor Shri Kulkarni, the George Ellery Hale Professor of Astronomy and Planetary Science at Caltech; Anna Ho (MS ’17, PhD ’20) and David Khatami of The University of California-Berkeley (US); Pavel Medvedev, Sergey Sazonov, Marat Gilfanov, Georgii Khorunzhev, and Rashid Sunyaev of IKI – The Space Research Institute of Russian Academy of Sciences [Росси́йская акаде́мия нау́к;(РАН) Rossíiskaya akadémiya naúk](RU); Nayana A.J. of The Indian Institute of Astrophysics[भारतीय खगोल भौतिकी संस्थान](IN); Daniel Perley of The Liverpool John Moores University (UK); and Poonam Chandra of The National Centre for Radio Astrophysics [राष्ट्रीय रेडियो खगोल भौतिकी केन्द्र](IN). Sazonov is also affiliated with The Moscow Institute of Physics and Technology [Московский Физико-Технический институт] (RU), and Gilfanov and Sunyaev are affiliated with The MPG Institute for Astrophysics [Max-Planck-Institut für Astrophysik] (DE).

“We can see down into the heart of these explosions to directly witness the birth of black holes and neutron stars,” she says, noting the supernovae are not cloaked by material.

The first Cow event, AT2018cow, shocked astronomers when it was discovered in 2018: the stellar explosion was 10 times brighter in visible light than typical supernovae and faded more quickly. It also gave off a large amount of highly variable X-rays, leading astronomers to believe that they were directly witnessing the birth of a black hole or neutron star for the first time.

Another distinguishing factor of Cows is that they throw off heaps of mass before they explode, and this mass gets illuminated later, after the explosion. When the stars blow up, they generate shock waves that are thought to plow through the pre-existing material, causing them to glow in radio and millimeter-wavelength light.

AT2020mrf is the first to be found initially in X-rays rather than optical light. Yao and her colleagues spotted the event in July 2020 using X-ray data from the Russian–German Spektrum-Roentgen-Gamma (SRG) telescope.

eRosita DLR/ MPG, on Russian German space telescope The Russian-German space probe Spektrum-Roentgen-Gamma (SRG).

The eROSITA X-ray telescope with 7 mirror modules and 54 mirror shells each combined with 7 specially built X-ray cameras. Credit: MPE.

eROSITA built by MPG Institute for Extraterrestrial Physics [MPG Institut für Extraterrestrische Physik](DE) aboard the Spectrum-Roentgen-Gamma (SRG)(RU) satellite.

They checked observations taken in optical light by the Zwicky Transient Facility (ZTF), which operates from Caltech’s Palomar Observatory, and found that ZTF had also spotted the event.

Zwicky Transient Facility (ZTF) instrument installed on the 1.2m diameter Samuel Oschin Telescope at Palomar Observatory in California. Credit: Caltech Optical Observatories

Caltech Palomar Samuel Oschin 48 inch Telescope, located in San Diego County, California, U.S.A., altitude 1,712 m (5,617 ft). Credit: Caltech.

The SRG data revealed that this explosion initially shined with 20 times more X-ray light than the original Cow event. Data captured one year later by NASA’s Chandra X-Ray Observatory showed that the explosion was not only still sizzling but shining with 200 times more X-ray light than that detected from the original Cow event over a similar timeframe.

The National Aeronautics and Space Administration Chandra X-ray telescope(US).

“When I saw the Chandra data, I didn’t believe the analysis at first,” Yao says. “I reran the analysis several times. This is the brightest Cow supernova seen to date in X-rays.”

Astronomers say that a “central engine” within the supernova debris must be powering the intense, ongoing X-ray radiation.

“The large amount of energy release and the fast X-ray variability seen in AT2020mrf provide strong evidence that the nature of the central engine is either a very active black hole or a rapidly spinning neutron star called a magnetar,” Yao says. “In Cow-like events, we still don’t know why the central engine is so active, but it probably has something to do with the type of the progenitor star being different from normal explosions.”

Because this event did not look exactly like the other four Cow-like events, Yao says this new class of supernovae is more diverse than originally thought. “Finding more members of this class will help us narrow in on the source of their power,” she says.

See the full article here .

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

Please help promote STEM in your local schools.

Stem Education Coalition

Caltech campus

The The California Institute of Technology (US) is a private research university in Pasadena, California. The university is known for its strength in science and engineering, and is one among a small group of institutes of technology in the United States which is primarily devoted to the instruction of pure and applied sciences.

The California Institute of Technology was founded as a preparatory and vocational school by Amos G. Throop in 1891 and began attracting influential scientists such as George Ellery Hale, Arthur Amos Noyes, and Robert Andrews Millikan in the early 20th century. The vocational and preparatory schools were disbanded and spun off in 1910 and the college assumed its present name in 1920. In 1934, The California Institute of Technology was elected to the Association of American Universities, and the antecedents of National Aeronautics and Space Administration (US)’s Jet Propulsion Laboratory, which The California Institute of Technology continues to manage and operate, were established between 1936 and 1943 under Theodore von Kármán.

The California Institute of Technology has six academic divisions with strong emphasis on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. First-year students are required to live on campus, and 95% of undergraduates remain in the on-campus House System at The California Institute of Technology. Although The California Institute of Technology has a strong tradition of practical jokes and pranks, student life is governed by an honor code which allows faculty to assign take-home examinations. The The California Institute of Technology Beavers compete in 13 intercollegiate sports in the NCAA Division III’s Southern California Intercollegiate Athletic Conference (SCIAC).

As of October 2020, there are 76 Nobel laureates who have been affiliated with The California Institute of Technology, including 40 alumni and faculty members (41 prizes, with chemist Linus Pauling being the only individual in history to win two unshared prizes). In addition, 4 Fields Medalists and 6 Turing Award winners have been affiliated with The California Institute of Technology. There are 8 Crafoord Laureates and 56 non-emeritus faculty members (as well as many emeritus faculty members) who have been elected to one of the United States National Academies. Four Chief Scientists of the U.S. Air Force and 71 have won the United States National Medal of Science or Technology. Numerous faculty members are associated with the Howard Hughes Medical Institute(US) as well as National Aeronautics and Space Administration(US). According to a 2015 Pomona College(US) study, The California Institute of Technology ranked number one in the U.S. for the percentage of its graduates who go on to earn a PhD.

Research

The California Institute of Technology is classified among “R1: Doctoral Universities – Very High Research Activity”. Caltech was elected to The Association of American Universities in 1934 and remains a research university with “very high” research activity, primarily in STEM fields. The largest federal agencies contributing to research are National Aeronautics and Space Administration(US); National Science Foundation(US); Department of Health and Human Services(US); Department of Defense(US), and Department of Energy(US).

In 2005, The California Institute of Technology had 739,000 square feet (68,700 m^2) dedicated to research: 330,000 square feet (30,700 m^2) to physical sciences, 163,000 square feet (15,100 m^2) to engineering, and 160,000 square feet (14,900 m^2) to biological sciences.

In addition to managing NASA-JPL/Caltech (US), The California Institute of Technology also operates the Caltech Palomar Observatory(US); the Owens Valley Radio Observatory(US);the Caltech Submillimeter Observatory(US); the W. M. Keck Observatory at the Mauna Kea Observatory(US); the Laser Interferometer Gravitational-Wave Observatory at Livingston, Louisiana and Richland, Washington; and Kerckhoff Marine Laboratory(US) in Corona del Mar, California. The Institute launched the Kavli Nanoscience Institute at The California Institute of Technology in 2006; the Keck Institute for Space Studies in 2008; and is also the current home for the Einstein Papers Project. The Spitzer Science Center(US), part of the Infrared Processing and Analysis Center(US) located on The California Institute of Technology campus, is the data analysis and community support center for NASA’s Spitzer Infrared Space Telescope [no longer in service].

The California Institute of Technology partnered with University of California at Los Angeles(US) to establish a Joint Center for Translational Medicine (UCLA-Caltech JCTM), which conducts experimental research into clinical applications, including the diagnosis and treatment of diseases such as cancer.

The California Institute of Technology operates several Total Carbon Column Observing Network(US) stations as part of an international collaborative effort of measuring greenhouse gases globally. One station is on campus.

From The California Institute of Technology (US) : “Transforming Materials with Light”

From The California Institute of Technology (US)

December 08, 2021
Whitney Clavin
(626) 395‑1944
wclavin@caltech.edu

Imagine windows that can easily transform into mirrors, or super high-speed computers that run not on electrons but light. These are just some of the potential applications that could emerge from optical engineering, the practice of using lasers to rapidly and temporarily change the properties of materials.

A strong laser is seen illuminating a material in a low-temperature chamber. The laser is being used to change the material’s degree of transparency. Credit: David Hsieh Laboratory/ Caltech.

“These tools could let you transform the electronic properties of materials at the flick of a light switch,” says Caltech Professor of Physics David Hsieh. “But the technologies have been limited by the problem of the lasers creating too much heat in the materials.”

In a new study in Nature, Hsieh and his team, including lead author and graduate student Junyi Shan, report success at using lasers to dramatically sculpt the properties of materials without the production of any excess damaging heat.

“The lasers required for these experiments are very powerful, so it’s hard to not heat up and damage the materials,” says Shan. “On the one hand, we want the material to be subjected to very intense laser light. On the other hand, we don’t want the material to absorb any of that light at all.”

The team found a “sweet spot” to get around this, Shan says, where the frequency of the laser is fine-tuned in such a way to markedly change the material’s properties without imparting any unwanted heat.

The scientists also say they found an ideal material to demonstrate this method. The material, a semiconductor called manganese phosphorus trisulphide, naturally absorbs only a small amount of light over a broad range of infrared frequencies. For their experiments, Hsieh, Shan, and colleagues used intense infrared laser pulses, each lasting about 10-13 seconds, to rapidly change the energy of electrons inside the material. As a result, the material shifted from a highly opaque state to a highly transparent one for certain colors of light.

Even more critical, the researchers say, is that the process is reversible. When the laser turns off, the material instantly goes back to its original state completely unscathed. This would not be possible if the material had absorbed the laser light and heated up because it would take a long time for the material to dissipate the heat. The heat-free manipulation used in the new process is known as “coherent optical engineering.”

The method works because the light alters the differences between the energy levels of electrons in the semiconductor (called band gaps) without kicking the electrons themselves into different energy levels, which is what generates heat.

“It’s as if you have a boat, and then a big wave comes along and vigorously rocks the boat up and down without causing any of the passengers to fall down,” explains Hsieh. “Our laser is vigorously rocking the energy levels of the material, and that alters the materials’ properties, but the electrons stay put.”

Researchers have previously theorized how this method would work. For example, in the 1960s, Caltech alumnus Jon H. Shirley (PhD ’63), put forth mathematical ideas about how to solve for electron-energy levels in a material in the presence of light. Building on this work, Hsieh’s Caltech team collaborated with theorists Mengxing Ye and Leon Balents from UC Santa Barbara to calculate the expected effects of laser illumination in manganese phosphorus trisulphide. The theory matched the experiments with “remarkable” accuracy, says Hsieh.

The findings, Hsieh says, mean that other researchers can now potentially use light to artificially create materials, such as exotic quantum magnets, which would have been otherwise difficult or even impossible to create naturally.

“In principle, this method can change optical, magnetic, and many other properties of materials,” says Shan. “This is an alternative way of doing materials science. Rather than making new materials to realize different properties, we can take just one material and ultimately give it a broad range of useful properties.”

The study was funded by the Army Research Office; the David and Lucile Packard Foundation; the National Science Foundation via the Institute for Quantum Information and Matter at Caltech and via The University of California-Santa Barbara (US); the Gordon and Betty Moore Foundation; and the National Research Foundation of Korea. Other authors include Hao Chu (PhD ’17), as well as Sungmin Lee and Je-Geun Park of The Seoul National University [서울대학교](KR).

See the full article here .

five-ways-keep-your-child-safe-school-shootings
Please help promote STEM in your local schools.

Stem Education Coalition

Caltech campus

The California Institute of Technology (US) is a private research university in Pasadena, California. The university is known for its strength in science and engineering, and is one among a small group of institutes of technology in the United States which is primarily devoted to the instruction of pure and applied sciences.

Caltech was founded as a preparatory and vocational school by Amos G. Throop in 1891 and began attracting influential scientists such as George Ellery Hale, Arthur Amos Noyes, and Robert Andrews Millikan in the early 20th century. The vocational and preparatory schools were disbanded and spun off in 1910 and the college assumed its present name in 1920. In 1934, Caltech was elected to the Association of American Universities, and the antecedents of National Aeronautics and Space Administration (US)’s Jet Propulsion Laboratory, which Caltech continues to manage and operate, were established between 1936 and 1943 under Theodore von Kármán.

Caltech has six academic divisions with strong emphasis on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. First-year students are required to live on campus, and 95% of undergraduates remain in the on-campus House System at Caltech. Although Caltech has a strong tradition of practical jokes and pranks, student life is governed by an honor code which allows faculty to assign take-home examinations. The Caltech Beavers compete in 13 intercollegiate sports in the NCAA Division III’s Southern California Intercollegiate Athletic Conference (SCIAC).

As of October 2020, there are 76 Nobel laureates who have been affiliated with Caltech, including 40 alumni and faculty members (41 prizes, with chemist Linus Pauling being the only individual in history to win two unshared prizes). In addition, 4 Fields Medalists and 6 Turing Award winners have been affiliated with Caltech. There are 8 Crafoord Laureates and 56 non-emeritus faculty members (as well as many emeritus faculty members) who have been elected to one of the United States National Academies. Four Chief Scientists of the U.S. Air Force and 71 have won the United States National Medal of Science or Technology. Numerous faculty members are associated with the Howard Hughes Medical Institute(US) as well as National Aeronautics and Space Administration(US). According to a 2015 Pomona College(US) study, Caltech ranked number one in the U.S. for the percentage of its graduates who go on to earn a PhD.

Research

Caltech is classified among “R1: Doctoral Universities – Very High Research Activity”. Caltech was elected to the Association of American Universities in 1934 and remains a research university with “very high” research activity, primarily in STEM fields. The largest federal agencies contributing to research are National Aeronautics and Space Administration(US); National Science Foundation(US); Department of Health and Human Services(US); Department of Defense(US), and Department of Energy(US).

In 2005, Caltech had 739,000 square feet (68,700 m^2) dedicated to research: 330,000 square feet (30,700 m^2) to physical sciences, 163,000 square feet (15,100 m^2) to engineering, and 160,000 square feet (14,900 m^2) to biological sciences.

In addition to managing JPL, Caltech also operates The Caltech Palomar Observatory(US); The Owens Valley Radio Observatory(US); The Caltech Submillimeter Observatory(US); The W. M. Keck Observatory at The Mauna Kea Observatory(US); The Laser Interferometer Gravitational-Wave Observatory at Livingston, Louisiana and Richland, Washington; and The Kerckhoff Marine Laboratory(in Corona del Mar, California. US)

The Institute launched The Kavli Nanoscience Institute at Caltech in 2006 ; The Keck Institute for Space Studies in 2008; and is also the current home for the Einstein Papers Project.

The Spitzer Science Center(US) is part of The Infrared Processing and Analysis Center(US) located on the Caltech campus, the data analysis and community support center for NASA’s Spitzer Infrared Space Telescope [no longer in service].

Caltech partnered with The University of California at Los Angeles(US) to establish a Joint Center for Translational Medicine (UCLA-Caltech JCTM), which conducts experimental research into clinical applications, including the diagnosis and treatment of diseases such as cancer.

Caltech operates several

From The California Institute of Technology (US) : “Exoplanet Bonanza”

From The California Institute of Technology (US)

December 01, 2021

Whitney Clavin
(626) 395‑1944
wclavin@caltech.edu

Artist’s rendering of two Saturn-sized planets orbiting a Sun-like star called EPIC 249731291, in orbits so tight their atmospheres are perpetual infernos. Image credit: R. Hurt (The Caltech IPAC-Infrared Processing and Analysis Center (US)) JPL/Caltech-NASA(US)

New planetary candidates found by sifting through archival Kepler Telescope data.

NASA Kepler Space Telescope (US).

A fully automated exoplanet-detection system sifted through years of data from NASA’s retired Kepler Space Telescope yielding a torrent of discoveries including 172 new possible exoplanets. Exoplanets are planets that orbit stars beyond our sun.

“There was a lot of unexplored territory in these NASA Kepler archival data, so we worked together to build a new software pipeline that could uniformly look through the final four years of observations,” says Jessie Christiansen, lead scientist for the NASA Exoplanet Archive at The Caltech IPAC-Infrared Processing and Analysis Center (US) and co-author of a new study reporting the findings in The Astronomical Journal. “These efforts included creating a new tool for gleaning the astrophysical signals from instrumental signals, which had plagued many previous analyses.” The lead author of the study is Jon Zink, a Sagan Postdoctoral Scholar Research Associate in Astronomy at Caltech, who performed the research while a graduate student at The University of California-Los Angeles (US).

The Kepler Space Telescope, which was shut down in 2018 after running dry of fuel, explored the galaxy for nine years and found thousands of exoplanets. More than 2,800 have been confirmed, and more than 3,250 candidate planets await confirmation, including the latest batch of 172 candidates. Hundreds of these candidates were detected during Kepler’s second mission, known as K2, after mechanical failure ended the first mission and sharply limited observing capability for the second.

The new catalog drawn from Kepler’s K2 observations includes some truly bizarre planets and planetary systems. In one system, called EPIC 249559552, two “mini Neptunes” are locked in a gravitational dance, with the inner planet making five orbits for every two by the outer planet. In another system, called EPIC 249731291, two planets a bit smaller than Saturn are orbiting so close to their host star that that their atmospheres are perpetual infernos.

The new exoplanet catalog was compiled by a team of astronomers from several institutions. Other Caltech-affiliated authors include Kevin Hardegree-Ullman, a former Caltech postdoc now at The University of Arizona (US), and volunteer researcher Sakhee Bhure.

“With a large, uniformly generated catalog like this one, we can begin performing population studies into how common different kinds of planets and planetary systems are,” says Christiansen.

See the full article here.

See also the JPL article here.

five-ways-keep-your-child-safe-school-shootings
Please help promote STEM in your local schools.

Stem Education Coalition

Caltech campus

The The California Institute of Technology (US) is a private research university in Pasadena, California. The university is known for its strength in science and engineering, and is one among a small group of institutes of technology in the United States which is primarily devoted to the instruction of pure and applied sciences.

Caltech was founded as a preparatory and vocational school by Amos G. Throop in 1891 and began attracting influential scientists such as George Ellery Hale, Arthur Amos Noyes, and Robert Andrews Millikan in the early 20th century. The vocational and preparatory schools were disbanded and spun off in 1910 and the college assumed its present name in 1920. In 1934, Caltech was elected to the Association of American Universities, and the antecedents of National Aeronautics and Space Administration (US)’s Jet Propulsion Laboratory, which Caltech continues to manage and operate, were established between 1936 and 1943 under Theodore von Kármán.

Caltech has six academic divisions with strong emphasis on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. First-year students are required to live on campus, and 95% of undergraduates remain in the on-campus House System at Caltech. Although Caltech has a strong tradition of practical jokes and pranks, student life is governed by an honor code which allows faculty to assign take-home examinations. The Caltech Beavers compete in 13 intercollegiate sports in the NCAA Division III’s Southern California Intercollegiate Athletic Conference (SCIAC).

As of October 2020, there are 76 Nobel laureates who have been affiliated with Caltech, including 40 alumni and faculty members (41 prizes, with chemist Linus Pauling being the only individual in history to win two unshared prizes). In addition, 4 Fields Medalists and 6 Turing Award winners have been affiliated with Caltech. There are 8 Crafoord Laureates and 56 non-emeritus faculty members (as well as many emeritus faculty members) who have been elected to one of the United States National Academies. Four Chief Scientists of the U.S. Air Force and 71 have won the United States National Medal of Science or Technology. Numerous faculty members are associated with the Howard Hughes Medical Institute(US) as well as National Aeronautics and Space Administration(US). According to a 2015 Pomona College(US) study, Caltech ranked number one in the U.S. for the percentage of its graduates who go on to earn a PhD.

Research

Caltech is classified among “R1: Doctoral Universities – Very High Research Activity”. Caltech was elected to the Association of American Universities in 1934 and remains a research university with “very high” research activity, primarily in STEM fields. The largest federal agencies contributing to research are National Aeronautics and Space Administration(US); National Science Foundation(US); Department of Health and Human Services(US); Department of Defense(US), and Department of Energy(US).

In 2005, Caltech had 739,000 square feet (68,700 m^2) dedicated to research: 330,000 square feet (30,700 m^2) to physical sciences, 163,000 square feet (15,100 m^2) to engineering, and 160,000 square feet (14,900 m^2) to biological sciences.

In addition to managing JPL, Caltech also operates the Caltech Palomar Observatory(US); the Owens Valley Radio Observatory(US);the Caltech Submillimeter Observatory(US); the W. M. Keck Observatory at the Mauna Kea Observatory(US); the Laser Interferometer Gravitational-Wave Observatory at Livingston, Louisiana and Richland, Washington; and Kerckhoff Marine Laboratory(US) in Corona del Mar, California. The Institute launched the Kavli Nanoscience Institute at Caltech in 2006; the Keck Institute for Space Studies in 2008; and is also the current home for the Einstein Papers Project. The Spitzer Science Center(US), part of the Infrared Processing and Analysis Center(US) located on the Caltech campus, is the data analysis and community support center for NASA’s Spitzer Infrared Space Telescope [no longer in service].

Caltech partnered with University of California at Los Angeles(US) to establish a Joint Center for Translational Medicine (UCLA-Caltech JCTM), which conducts experimental research into clinical applications, including the diagnosis and treatment of diseases such as cancer.

Caltech operates several Total Carbon Column Observing Network(US) stations as part of an international collaborative effort of measuring greenhouse gases globally. One station is on campus.