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  • richardmitnick 3:03 pm on August 22, 2017 Permalink | Reply
    Tags: , , Newer cheaper approaches, , Physics,   

    From Symmetry: “Expanding the search for dark matter” 

    Symmetry Mag

    Symmetry

    08/22/17
    Lori Ann White

    At a recent meeting, scientists shared ideas for searching for dark matter on the (relative) cheap.

    Dark matter halo Image credit: Virgo consortium / A. Amblard / ESA

    Thirty-one years ago, scientists made their first attempt to find dark matter with a particle detector in a South Dakota mine.

    Since then, researchers have uncovered enough clues to think dark matter makes up approximately 26.8 percent of all the matter and energy in the universe. They think it forms a sort of gravitational scaffolding for the galaxies and galaxy clusters our telescopes do reveal, shaping the structure of our universe while remaining unseen.

    These conclusions are based on indirect evidence such as the behavior of galaxies and galaxy clusters. Direct detection experiments—ones designed to actually sense a dark matter particle pinging off the nucleus of an atom—have yet to find what they’re looking for. Nor has dark matter been seen at the Large Hadron Collider. That invisible, enigmatic material, that Greta Garbo of particle physics, still wants to be alone.

    It could be that researchers are just looking in the wrong place. Much of the search for dark matter has focused on particles called WIMPs, weakly interacting massive particles. But interest in WIMP alternatives has been growing, prompting the development of a variety of small-scale research projects to investigate some of the most promising prospects.

    In March more than 100 scientists met at the University of Maryland for “Cosmic Visions: New Ideas in Dark Matter,” a gathering to take the pulse of the post-WIMP dark matter landscape for the Department of Energy. That pulse was surprisingly strong. Organizers recently published a white paper detailing the results.

    The conference came about partly because, “it seemed a good time to get everyone together to see what each experiment was doing, where they reinforced each other and where they did something new,” says Natalia Toro, a theorist at SLAC National Accelerator Laboratory and a member of the Cosmic Visions Scientific Advisory Committee. What she and many other participants didn’t expect, Toro says, was just how many good ideas would be presented.

    Almost 50 experiments in various stages of development were presented during three days of talks, and a similar number of potential experiments were discussed.

    Some of the experiments presented would be designed to look for dark matter particles that are lighter than traditional WIMPs, or for the new fundamental forces through which such particles could interact. Others would look for oscillating forces produced by dark matter particles trillions of times lighter than the electron. Still others would look for different dark matter candidates, such as primordial black holes.

    The scientists at the workshop were surprised by how small and relatively inexpensive many of the experiments could be, says Philip Schuster, a particle theorist at SLAC National Accelerator Laboratory.

    “‘Small’ and ‘inexpensive’ depend on what technology you’re using, of course,” Schuster says. DOE is prepared to provide funding to the tune of $10 million (still a fraction of the cost of a current WIMP experiment), and many of the experiments could cost in the $1 to $2 million range.

    Several factors work together to lessen the cost. For example, advances in detector technology and quantum sensors have made technology cheaper. Then there are small detectors that can be placed at already-existing large facilities like the Heavy Photon Search, a dark-sector search at Jefferson Lab. “It’s basically a table-top detector, as opposed to CMS and ATLAS at the Large Hadron Collider, which took years to build and weigh as much as a battleship,” Schuster says.

    Experimentalist Joe Incandela of the University of California, Santa Barbara and one of the coordinators of the Cosmic Visions effort, has a simple explanation for this current explosion of ideas. “There’s a good synergy between the technology and interest in dark matter,” he says.

    Incandela says he is feeling the synergy himself. He is a former spokesperson for CMS, a battleship-class experiment in which he continues to play an active role while also developing the Light Dark Matter Experiment, which would use a high-resolution silicon-based calorimeter that he originally helped develop for CMS to search for an alternative to WIMPs.

    “It occurred to me that this calorimeter technology could very useful for low-mass dark matter searches,” he says. “My hope is that, starting soon, and spanning roughly five years, the funding—and not very much is needed—will be available to support experiments that can cover a lot more of the landscape where dark matter may be hiding. It’s very exciting.”

    See the full article here .

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    Symmetry is a joint Fermilab/SLAC publication.


     
  • richardmitnick 10:56 am on August 21, 2017 Permalink | Reply
    Tags: , Diamond rain, MEC-Matter in Extreme Conditions instrument, Physics, ,   

    From SLAC: “Scientists Create ‘Diamond Rain’ That Forms in the Interior of Icy Giant Planets” 


    SLAC Lab

    August 21, 2017
    Amanda Solliday
    solliday@slac.stanford.edu
    (650) 926-4496

    1
    A cutaway depicts the interior of Neptune (left). In an experiment conducted at the Linac Coherent Light Source, the team studied a plastic simulating compounds formed from methane—a molecule with just one carbon bound to four hydrogen atoms that causes the distinct blue cast of Neptune. Methane forms hydrocarbon (hydrogen and carbon) chains that respond to high pressure and temperature to form “diamond rain” in the interiors of icy giant planets like Neptune. The scientists were able to recreate similar conditions using high-powered optical lasers and watch the small diamonds form in real time with X-rays. (Greg Stewart/SLAC National Accelerator Laboratory)

    In an experiment designed to mimic the conditions deep inside the icy giant planets of our solar system, scientists were able to observe “diamond rain” for the first time as it formed in high-pressure conditions. Extremely high pressure squeezes hydrogen and carbon found in the interior of these planets to form solid diamonds that sink slowly down further into the interior.

    The glittering precipitation has long been hypothesized to arise more than 5,000 miles below the surface of Uranus and Neptune, created from commonly found mixtures of just hydrogen and carbon. The interiors of these planets are similar—both contain solid cores surrounded by a dense slush of different ices. With the icy planets in our solar system, “ice” refers to hydrogen molecules connected to lighter elements, such as carbon, oxygen and/or nitrogen.

    Researchers simulated the environment found inside these planets by creating shock waves in plastic with an intense optical laser at the Matter in Extreme Conditions (MEC) instrument at SLAC National Accelerator Laboratory’s X-ray free-electron laser, the Linac Coherent Light Source (LCLS).

    SLAC/LCLS

    SLAC is one of 10 Department of Energy (DOE) Office of Science laboratories.

    In the experiment, the scientists were able to see that nearly every carbon atom of the original plastic was incorporated into small diamond structures up to a few nanometers wide. On Uranus and Neptune, the study authors predict that diamonds would become much larger, maybe millions of carats in weight. Researchers also think it’s possible that over thousands of years, the diamonds slowly sink through the planets’ ice layers and assemble into a thick layer around the core.

    The research published in Nature Astronomy on August 21.

    “Previously, researchers could only assume that the diamonds had formed,” said Dominik Kraus, scientist at Helmholtz Zentrum Dresden-Rossendorf and lead author on the publication. “When I saw the results of this latest experiment, it was one of the best moments of my scientific career.”

    Earlier experiments that attempted to recreate diamond rain in similar conditions were not able to capture measurements in real time, because we currently can create these extreme conditions under which tiny diamonds form only for very brief time in the laboratory. The high-energy optical lasers at MEC combined with LCLS’s X-ray pulses—which last just femtoseconds, or quadrillionths of a second—allowed the scientists to directly measure the chemical reaction.

    Other prior experiments also saw hints of carbon forming graphite or diamond at lower pressures than the ones created in this experiment, but with other materials introduced and altering the reactions.

    The results presented in this experiment is the first unambiguous observation of high-pressure diamond formation from mixtures and agrees with theoretical predictions about the conditions under which such precipitation can form and will provide scientists with better information to describe and classify other worlds.

    Turning Plastic Into Diamond

    In the experiment, plastic simulates compounds formed from methane—a molecule with just one carbon bound to four hydrogen atoms that causes the distinct blue cast of Neptune.

    The team studied a plastic material, polystyrene, that is made from a mixture of hydrogen and carbon, key components of these planets’ overall chemical makeup.

    In the intermediate layers of icy giant planets, methane forms hydrocarbon (hydrogen and carbon) chains that were long hypothesized to respond to high pressure and temperature in deeper layers and form diamond rain.

    The researchers used high-powered optical laser to create pairs of shock waves in the plastic with the correct combination of temperature and pressure. The first shock is smaller and slower and overtaken by the stronger second shock. When the shock waves overlap, that’s the moment the pressure peaks and when most of the diamonds form, Kraus said.

    During those moments, the team probed the reaction with pulses of X-rays from LCLS that last just 50 femtoseconds. This allowed them to see the small diamonds that form in fractions of a second with a technique called femtosecond X-ray diffraction. The X-ray snapshots provide information about the size of the diamonds and the details of the chemical reaction as it occurs.

    “For this experiment, we had LCLS, the brightest X-ray source in the world,” said Siegfried Glenzer, professor of photon science at SLAC and a co-author of the paper. “You need these intense, fast pulses of X-rays to unambiguously see the structure of these diamonds, because they are only formed in the laboratory for such a very short time.”

    2
    The Matter in Extreme Conditions instrument at SLAC gives scientists the tools to investigate the extremely hot, dense matter at the centers of stars and giant planets. These experiments could help researchers design new materials with enhanced properties and recreate the nuclear fusion process that powers the sun. (SLAC National Accelerator Laboratory)

    Nanodiamonds at Work

    When astronomers observe exoplanets outside our solar system, they are able to measure two primary traits—the mass, which is measured by the wobble of stars, and radius, observed from the shadow when the planet passes in front of a star. The relationship between the two is used to classify a planet and help determine whether it may be composed of heavier or lighter elements.

    “With planets, the relationship between mass and radius can tell scientists quite a bit about the chemistry,” Kraus said. “And the chemistry that happens in the interior can provide additional information about some of the defining features of the planet.”

    Information from studies like this one about how elements mix and clump together under pressure in the interior of a given planet can change the way scientists calculate the relationship between mass and radius, allowing scientists to better model and classify individual planets. The falling diamond rain also could be an additional source of energy, generating heat while sinking towards the core.

    “We can’t go inside the planets and look at them, so these laboratory experiments complement satellite and telescope observations,” Kraus said.

    The researchers also plan to apply the same methods to look at other processes that occur in the interiors of planets.

    In addition to the insights they give into planetary science, nanodiamonds made on Earth could potentially be harvested for commercial purposes—uses that span medicine, scientific equipment and electronics. Currently, nanodiamonds are commercially produced from explosives; laser production may offer a cleaner and more easily controlled method.

    Research that compresses matter, like this study, also helps scientists understand and improve fusion experiments where forms of hydrogen combine to form helium to generate vast amounts of energy. This is the process that fuels the sun and other stars but has yet to be realized in a controlled way for power plants on Earth.

    In some fusion experiments, a fuel of two different forms of hydrogen is surrounded by a plastic layer that reaches conditions similar to the interior of planets during a short-lived compression stage. The LCLS experiment on plastic now suggests that chemistry may play an important role in this stage.

    “Simulations don’t really capture what we’re observing in this field,” Glenzer said. “Our study and others provide evidence that matter clumping in these types of high-pressure conditions is a force to be reckoned with.”

    The research collaboration includes scientists from Helmholtz Zentrum Dresden-Rossendorf in Germany, University of California-Berkeley, Lawrence Livermore National Laboratory, Lawrence Berkeley National Laboratory, GSI Helmholtz Center for Heavy Ion Research in Germany, Osaka University in Japan, Technical University of Darmstadt in Germany, European XFEL, University of Michigan, University of Warwick in the United Kingdom and SLAC.

    The research was supported by DOE’s Office of Science and the National Nuclear Security Administration. LCLS is a DOE Office of Science User Facility.

    See the full article here .

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    SLAC Campus
    SLAC is a multi-program laboratory exploring frontier questions in photon science, astrophysics, particle physics and accelerator research. Located in Menlo Park, California, SLAC is operated by Stanford University for the DOE’s Office of Science.
    i1

     
  • richardmitnick 1:56 pm on August 17, 2017 Permalink | Reply
    Tags: , , , , MPG Institute for Nuclear Physics, Physics,   

    From MPG Institute for Nuclear Physics: “Sharp x-ray pulses from the atomic nucleus” 

    Max Planck Gesellschaft Institute for Nuclear Physics

    August 17, 2017
    PD Dr. Jörg Evers
    Research Group Leader
    Max Planck Institute for Nuclear Physics, Heidelberg
    Phone:+49 6221 516-177
    joerg.evers@mpi-hd.mpg.de

    Prof. Dr. Thomas Pfeifer
    Max Planck Institute for Nuclear Physics, Heidelberg
    Phone:+49 6221 516-380Fax:+49 6221 516-802
    Thomas.Pfeifer@mpi-hd.mpg.de

    Honorary Professor Dr. Christoph H. Keitel
    Max Planck Institute for Nuclear Physics, Heidelberg
    Phone:+49 6221 516-150Fax:+49 6221 516-152
    keitel@mpi-hd.mpg

    Using a mechanical trick, scientists have succeeded in narrowing the spectrum of the pulses emitted by x-ray lasers.

    X-rays make the invisible visible: they permit the way materials are structured to be determined all the way down to the level of individual atoms. In the 1950s it was x-rays which revealed the double-helix structure of DNA. With new x-ray sources, such as the XFEL free-electron laser in Hamburg, it is even possible to “film” chemical reactions.

    XFEL


    XFEL map

    The results obtained from studies using these new x-ray sources may be about to become even more precise. A team around Kilian Heeg from the Max Planck Institute for Nuclear Physics in Heidelberg has now found a way to make the spectrum of the x-ray pulses emitted by these sources even narrower. In contrast to standard lasers, which generate light of a single colour and wavelength, x-ray sources generally produce pulses with a broad spectrum of different wavelengths. Sharper pulses could soon drive applications that were previously not feasible. This includes testing physical constants and measuring lengths and times even more precisely than can be achieved at present.

    1
    Upgrading x-ray lasers – a mechanical trick can be used to narrow the spectrum of the pulses emitted by x-ray lasers such as the XFEL free electron laser shown here. This would enable x-ray lasers to be used for experiments which would otherwise not be possible, for example testing whether physical constants are really constant. © DESY, Hamburg

    Researchers use light and other electromagnetic radiation for developing new materials at work in electronics, automobiles, aircraft or power plants, as well as for studies on biomolecules such as protein function. Electromagnetic radiation is also the tool of choice for observing chemical reactions and physical processes in the micro and nano ranges. Different types of spectroscopy use different individual wavelengths to stimulate characteristic oscillations in specific components of a structure. Which wavelengths interact with the structure – physicists use the term resonance – tells us something about their composition and how they are constructed; for example, how atoms within a molecule are arranged in space.

    In contrast to visible light, which has a much lower energy, x-rays can trigger resonance not just in the electron shell of an atom, but also deep in the atomic core, its nucleus. X-ray spectroscopy therefore provides unique knowledge about materials. In addition, the resonances of some atomic nuclei are very sharp, in principle allowing extremely precise measurements.

    X-ray sources generate ultra-short flashes with a broad spectrum

    Modern x-ray sources such as the XFEL free electron laser in Hamburg and the PETRA III (Hamburg), and ESRF (Grenoble) synchrotron sources are prime candidates for carrying out such studies.

    DESI Petra III

    ESRF. Grenoble, France

    Free- electron lasers in particular are optimized for generating very short x-ray flashes, which are primarily used to study very fast processes in the microscopic world of atoms and molecules. Ultra short light pulses, however, in turn have a broad spectrum of wavelengths. Consequently, only a small fraction of the light is at the right wavelength to cause resonance in the sample. The rest passes straight through the sample, making spectroscopy of sharp resonances rather inefficient.

    It is possible to generate a very sharp x-ray spectrum – i.e. x-rays of a single wavelength – using filters; however, since this involves removing unused wavelengths, the resulting resonance signal is still weak.

    The new method developed by the researchers in Heidelberg delivers a three to four-fold increase in the intensity of the resonance signal. Together with scientists from DESY in Hamburg and ESRF in Grenoble, Kilian Heeg and Jörg Evers from Christoph Keitel’s Division and a team around Thomas Pfeifer at the Max Planck Institute for Nuclear Physics in Heidelberg have succeeded in making some of the x-ray radiation that would not normally interact with the sample contribute to the resonance signal. They have successfully tested their method on iron nuclei both at the ESRF in Grenoble and at the PETRA III synchrotron of DESY in Hamburg.

    A tiny jolt amplifies the radiation

    The researchers’ approach to amplifying the x-rays is based on the fact that, when x-rays interact with iron nuclei (or any other nuclei) to produce resonance, they are re-emitted after a short delay. These re-emitted x-rays then lag exactly half a wavelength behind that part of the radiation which has passed straight through. This means that the peaks of one wave coincide exactly with the troughs of the other wave, with the result that they cancel each other out. This destructive interference attenuates the X-ray pulses at the resonant wavelength, which is also the fundamental origin of absorption of light.

    “We utilize the time window of about 100 nanoseconds before the iron nuclei re-emit the x-rays,” explains project leader Jörg Evers. During this time window, the researchers move the iron foil by about 40 billionths of a millimetre (0.4 angstroms). This tiny jolt has the effect of producing constructive interference between the emitted and transmitted light waves. “It’s as if two rivers, the waves on one of which are offset by half a wavelength from the waves on the other, meet,” says Evers, “and you shift one of the rivers by exactly this distance.” This has the effect that, after the rivers meet, the waves on the two rivers move in time with each other. Wave peaks coincide with wave peaks and the waves amplify, rather than attenuating, each other. This trick, however, does not just work on light at the resonance wavelengths, but also has the reverse effect (i.e. attenuation) on a broader range of wavelengths around the resonance wavelength. Kilian Heeg puts it like this. “We squeeze otherwise unused x-ray radiation into the resonance.”

    To enable the physicists to move the iron foil fast enough and precisely enough, it is mounted on a piezoelectric crystal. This crystal expands or contracts in response to an applied electrical voltage. Using a specially developed computer program, the Heidelberg-based researchers were able to adjust the electrical signal that controls the piezoelectric crystal to maximize the amplification of the resonance signal.

    Applications in length measurement and atomic clocks

    The researchers see a wide range of potential applications for their new technique. According to Thomas Pfeifer, the procedure will expand the utility of new high-power x-ray sources for high-resolution x-ray spectroscopy. This will enable more accurate modelling of what happens in atoms and molecules. Pfeifer also stresses the utility of the technique in metrology, in particular for high-precision measurements of lengths and the quantum-mechanical definition of time. “With x-rays, it is possible to measure lengths 10,000 times more accurately than with visible light,” explains Pfeifer. This can be used to study and optimize nanostructures such as computer chips and newly developed batteries. Pfeifer also envisages x-ray atomic clocks which are far more precise than even the most advanced optical atomic clocks nowadays based on visible light.

    Not least, better X-ray spectroscopy could enable us to answer one of physics’ great unanswered questions – whether physical constants really are constant or whether they change slowly with time. If the latter were true, resonance lines would drift slowly over time. Extremely sharp x-ray spectra would make it possible to determine whether this is the case over a relatively short period.

    Evers reckons that, once mature, the technique would be relatively easy to integrate into experiments at DESY and ESRF. “It should be possible to make a shoe-box sized device that could be rapidly installed and, according to our calculations, could enable an approximately 10-fold amplification,” he adds.

    Science paper:
    Spectral narrowing of x-ray pulses for precision spectroscopy with nuclear resonances
    http://science.sciencemag.org/content/357/6349/375

    See the full article here .

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    The Max-Planck-Institut für Kernphysik (“MPI for Nuclear Physics” or MPIK for short) is a research institute in Heidelberg, Germany.

    The institute is one of the 80 institutes of the Max-Planck-Gesellschaft (Max Planck Society), an independent, non-profit research organization. The Max Planck Institute for Nuclear Physics was founded in 1958 under the leadership of Wolfgang Gentner. Its precursor was the Institute for Physics at the MPI for Medical Research.

    The Max Planck Society is Germany’s most successful research organization. Since its establishment in 1948, no fewer than 18 Nobel laureates have emerged from the ranks of its scientists, putting it on a par with the best and most prestigious research institutions worldwide. The more than 15,000 publications each year in internationally renowned scientific journals are proof of the outstanding research work conducted at Max Planck Institutes – and many of those articles are among the most-cited publications in the relevant field.

    What is the basis of this success? The scientific attractiveness of the Max Planck Society is based on its understanding of research: Max Planck Institutes are built up solely around the world’s leading researchers. They themselves define their research subjects and are given the best working conditions, as well as free reign in selecting their staff. This is the core of the Harnack principle, which dates back to Adolph von Harnack, the first president of the Kaiser Wilhelm Society, which was established in 1911. This principle has been successfully applied for nearly one hundred years. The Max Planck Society continues the tradition of its predecessor institution with this structural principle of the person-centered research organization.

    The currently 83 Max Planck Institutes and facilities conduct basic research in the service of the general public in the natural sciences, life sciences, social sciences, and the humanities. Max Planck Institutes focus on research fields that are particularly innovative, or that are especially demanding in terms of funding or time requirements. And their research spectrum is continually evolving: new institutes are established to find answers to seminal, forward-looking scientific questions, while others are closed when, for example, their research field has been widely established at universities. This continuous renewal preserves the scope the Max Planck Society needs to react quickly to pioneering scientific developments.

     
  • richardmitnick 12:46 pm on August 16, 2017 Permalink | Reply
    Tags: , As time passes and we still haven’t detected WIMPs, , , , Can Radio Telescopes Find Axions?, , , Galactic halo model, Magnetic fields can change axions to and from photons, , Physics,   

    From AAS NOVA: “Can Radio Telescopes Find Axions?” 

    AASNOVA

    American Astronomical Society

    16 August 2017
    Susanna Kohler

    1
    A simulation showing the distribution of dark matter in the universe. [AMNH]

    Dark matter halo Image credit: Virgo consortium / A. Amblard / ESA

    In the search for dark matter, the most commonly accepted candidates are invisible, massive particles commonly referred to as WIMPs. But as time passes and we still haven’t detected WIMPs, alternative scenarios are becoming more and more appealing. Prime among these is the idea of axions.

    2
    The Italian PVLAS is an example of a laboratory experiment that attempted to confirm the existence of axions. [PVLAS]

    A Bizarre Particle

    Axions are a type of particle first proposed in the late 1970s. These theorized particles arose from a new symmetry introduced to solve ongoing problems with the standard model for particle physics, and they were initially predicted to have more than a keV in mass. For this reason, their existence was expected to be quickly confirmed by particle-detector experiments — yet no detections were made.

    Today, after many unsuccessful searches, experiments and theory tell us that if axions exist, their masses must lie between 10-6–10-3 eV. This is minuscule — an electron’s mass is around 500,000 eV, and even neutrinos are on the scale of a tenth of an eV!

    But enough of anything, even something very low-mass, can weigh a lot. If they are real, then axions were likely created in abundance during the Big Bang — and unlike heavier particles, they can’t decay into anything lighter, so we would expect them all to still be around today. Our universe could therefore be filled with invisible axions, potentially providing an explanation for dark matter in the form of many, many tiny particles.

    4
    Artist’s impression of the central core of proposed Square Kilometer Array antennas. [SKA/Swinburne Astronomy Productions]

    How Do We Find Them?

    Axions barely interact with ordinary matter and they have no electric charge. One of the few ways we can detect them is with magnetic fields: magnetic fields can change axions to and from photons.

    While many studies have focused on attempting to detect axions in laboratory experiments, astronomy provides an alternative: we can search for cosmological axions. Now scientists Katharine Kelley and Peter Quinn at ICRAR, University of Western Australia, have explored how we might use next-generation radio telescopes to search for photons that were created by axions interacting with the magnetic fields of our galaxy.

    5
    Potential axion coupling strengths vs. mass (click for a closer look). The axion mass is thought to lie between a µeV and a meV; two theoretical models are shown with dashed lines. The plot shows the sensitivity of the upcoming SKA and its precursors, ASKAP and MEERKAT. [Kelley&Quinn 2017]

    SKA/ASKAP radio telescope at the Murchison Radio-astronomy Observatory (MRO) in Mid West region of Western Australia

    SKA Meerkat telescope, 90 km outside the small Northern Cape town of Carnarvon, SA

    Hope for Next-Gen Telescopes

    By using a simple galactic halo model and reasonable assumptions for the central galactic magnetic field — even taking into account the time dependence of the field — Kelley and Quinn estimate the radio-frequency power density that we would observe at Earth from axions being converted to photons within the Milky Way’s magnetic field.

    The authors then compare this signature to the detection capabilities of upcoming radio telescope arrays. They show that the upcoming Square Kilometer Array and its precursors should have the capability to detect signs of axions across large parts of parameter space.

    Kelley and Quinn conclude that there’s good cause for optimism about future radio telescopes’ ability to detect axions. And if we did succeed in making a detection, it would be a triumph for both particle physics and astrophysics, finally providing an explanation for the universe’s dark matter.

    Citation

    Katharine Kelley and P. J. Quinn 2017 ApJL 845 L4. doi:10.3847/2041-8213/aa808d

    Related Journal Articles
    See the full article for further references with links.

    See the full article here .

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    1

    AAS Mission and Vision Statement

    The mission of the American Astronomical Society is to enhance and share humanity’s scientific understanding of the Universe.

    The Society, through its publications, disseminates and archives the results of astronomical research. The Society also communicates and explains our understanding of the universe to the public.
    The Society facilitates and strengthens the interactions among members through professional meetings and other means. The Society supports member divisions representing specialized research and astronomical interests.
    The Society represents the goals of its community of members to the nation and the world. The Society also works with other scientific and educational societies to promote the advancement of science.
    The Society, through its members, trains, mentors and supports the next generation of astronomers. The Society supports and promotes increased participation of historically underrepresented groups in astronomy.
    The Society assists its members to develop their skills in the fields of education and public outreach at all levels. The Society promotes broad interest in astronomy, which enhances science literacy and leads many to careers in science and engineering.

    Adopted June 7, 2009

     
  • richardmitnick 5:43 pm on August 15, 2017 Permalink | Reply
    Tags: and Biomolecules / Serial Femtosecond Crystallography) instrument, , , Clusters, , Physics, Preparing for first user groups, The FXE (Femtosecond X-Ray Experiments) instrument, The SPB/SFX (Single Particles   

    From European XFEL: “First users invited to European XFEL” 

    XFEL bloc

    European XFEL

    15 August 2017
    No writer credit

    Facility preparing to welcome research groups to first two instruments.

    At European XFEL, a flurry of activity can be seen throughout the facility as staff prepare for the arrival of the first users in September. After years of development and construction, the world’s largest X-ray laser is now just weeks away from doing what it was designed to do: enabling scientists from across the world to push the frontiers of scientific knowledge.

    Underground in the experiment hall, the first two instruments are now getting ready for the first users. The FXE (Femtosecond X-Ray Experiments) instrument, coordinated by leading scientist Christian Bressler, will enable the research of extremely fast processes. Here it will be possible to create “molecular movies” showing the progression of chemical reactions which, for example, will help improve our understanding of how catalysts work, or how plants convert light into usable chemical energy. The SPB/SFX (Single Particles, Clusters, and Biomolecules / Serial Femtosecond Crystallography) instrument, coordinated by leading scientist Adrian Mancuso, will be used to gain a better understanding of the shape and function of biomolecules, such as proteins, that are otherwise difficult to study.

    More than 60 user groups answered a call for proposals issued in early 2017 for access to these two instruments. The project proposals were evaluated by international committees of experts on the basis of scientific merit and technical feasibility. The first 14 groups of scientists have now been selected and invited to carry out their ambitious research projects at the facility from September 2017.

    1
    The SPB/SFX instrument will enable novel studies of structural biology. It is one of two instruments that will be available for users in fall 2017. European XFEL

    2
    The FXE instrument will enable studies of ultrafast processes, such as the intermediate steps of chemical reactions. The instrument uses the ultrashort pulses of the European XFEL to create sequential images of reacting molecules, producing a slow-motion molecular movie of a previously invisible process. The FXE instrument is one of two instruments that will be available to users in fall 2017. European XFEL

    See the full article here .

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    XFEL Campus

    The Hamburg area will soon boast a research facility of superlatives: The European XFEL will generate ultrashort X-ray flashes—27 000 times per second and with a brilliance that is a billion times higher than that of the best conventional X-ray radiation sources.

    The outstanding characteristics of the facility are unique worldwide. Starting in 2017, it will open up completely new research opportunities for scientists and industrial users.

     
  • richardmitnick 12:16 pm on August 12, 2017 Permalink | Reply
    Tags: ALPIDE chip, , , Desk cosmic ray detector, , Physics, The ALPIDE chip is a CMOS monolithic active pixel sensor   

    From ALICE at CERN: “A desk cosmic ray detector for schools using the ALPIDE chip” 

    CERN
    CERN New Masthead

    11 August 2017
    Virginia Greco

    An educational and outreach project conceived by the ALICE ITS team is now moving forward rapidly thanks to Matthew Aquilina, who has joined the collaboration as a summer student, and his supervisors Magnus Mager and Felix Reidt.

    1
    Magnus Mager (left) and Matthew Aquilina (right). In the center, a prototype of compact cosmic ray detector based on the ALPIDE chip. [Credits: Virginia Greco]

    Would you like to have your own cheap and compact cosmic ray detector, sitting right on your desk? It sounds much like a nerdy fantasy, but indeed such a device can be realized and become a very useful educational and outreach tool.

    This was the idea inspiring the ALICE ITS team at CERN, who decided to use the pixel sensor chip (ALPIDE) to build a small and easy-to-operate cosmic ray detector. The project is now taking off thanks to the involvement of Matthew Aquilina – a summer student from Malta who joined the group at the end of June – and his supervisors Magnus Mager and Felix Reidt.

    The ALPIDE chip is a CMOS monolithic active pixel sensor being developed for the upgrade of the ITS of the ALICE experiment and characterized by very high detection efficiency.

    Some spare ALPIDE chips could be diverted to this pedagogical project, in which they are used to detect muons and electrons from cosmic rays. By making a stack of up to four chips, connected one-to-one, it is possible to reconstruct the trajectory of a particle crossing them. Considering an average rate of one cosmic ray per square centimeter per minute, with its active area of 1.4cm x 3cm, the ALPIDE chip registers a hit every few seconds. Because of the acceptance limitation in terms of solid angle due to the setup, the reconstruction rate is around 1 cosmic ray track per minute.

    “The ALPIDE chip is very good for this application since it has very low noise,” explains Magnus. “In addition, it has a multiple-event buffer that allow acquiring new data while we are reading out the previous, so essentially it is dead-time free.”

    2
    In order to target educational and outreach activities, a dedicated, cost-effective, and easy to use readout system was devised. It was decided to interface the chip to an Arduino microprocessor board, which is largely used for being very versatile and easy to program.

    The setup of the compact cosmic ray detector, thus, includes an Arduino card and up to four boards hosting each an ALPIDE chip, one on top of the other. “Programming the Arduino microprocessor to communicate with the chips turned out to be fairly easy,” Magnus comments, “but we still needed an interface to allow people having no specific technical expertise to operate the system.”

    Here is when Matthew came in. His main task, in fact, is to develop a user-friendly interface to control the system, with the aim to make it ‘plug and play’. He is employing the Unity platform, which is free software meant for developing 3D games but can also be used to make interfaces with 3D objects and operation menus. In this specific case, the user will be able to see on the screen the four detector planes, the pixel detectors on them and, when a cosmic ray crosses their active area, the corresponding hit in each plane. The work is still in progress but is moving forward rapidly.

    “When I started, first of all I had to study the Arduino-ALPIDE communication protocol, which meant going through the 110-page ALPIDE manual,” Matthew explains; “during the second week, I interfaced the microprocessor with Unity and then I started developing the user-friendly interface”. Indeed, he was chosen by Magnus and his colleagues among many candidates for his previous experience with the Unity software, which he had gained by developing a 3D game with it.

    A potential future development for the project is to allow data saving in exportable file formats to be read by other programs, so that some data analysis – such as angular distribution of the cosmic rays, day/night dependence and season dependence – could be performed.

    Once the user-friendly interface is done, it will be time to ‘advertise’ the project and make the system available to teachers and students. Some channels to take into consideration are the CERN teacher programmes and the CERN S’Cool Lab. “This device can be useful both for computer science and physics classes,” adds Magnus, “because students can learn about cosmic rays and detectors as well as how to program Arduino to communicate with a custom chip.”

    It can also be used for outreach purposes in some special event, such as the CERN open days.

    Matthew, on his side, is already profiting of this project, since he is enhancing his programming skills and is learning about physics and electronics. At the fourth year of his undergraduate engineering course at the University of Malta, Matthew applied to the CERN summer student programme attracted by the perspective of spending some time at CERN and because he was willing to have an experience outside his country.

    “I think I will continue my studies enrolling in a Master’s and a PhD programme, but I am not sure about the topic yet,” he declares. “Actually, at high-school I studied mainly chemistry and biology, then at the University I switched to engineering. I think I will continue with something that incorporates programming and electronics, such as robotics”.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    Meet CERN in a variety of places:


    Cern Courier

    THE FOUR MAJOR PROJECT COLLABORATIONS
    ATLAS
    CERN/ATLAS detector

    ALICE
    CERN ALICE New

    CMS
    CERN/CMS Detector

    LHCb

    CERN/LHCb

    LHC

    CERN/LHC Map
    CERN LHC Grand Tunnel

    CERN LHC particles


    Quantum Diaries

     
  • richardmitnick 11:10 am on August 12, 2017 Permalink | Reply
    Tags: , , , , Physics, , Solar core spins four times faster than expected,   

    From physicsworld.com: “Solar core spins four times faster than expected” 

    physicsworld
    physicsworld.com

    Aug 11, 2017
    Keith Cooper

    1
    Sunny science: the Sun still holds some mysteries for researchers. No image credit.

    The Sun’s core rotates four times faster than its outer layers – and the elemental composition of its corona is linked to the 11 year cycle of solar magnetic activity. These two findings have been made by astronomers using a pair of orbiting solar telescopes – NASA’s Solar Dynamics Observatory (SDO) and the joint NASA–ESA Solar and Heliospheric Observatory (SOHO). The researchers believe their conclusions could revolutionize our understanding of the Sun’s structure.

    NASA/SDO

    ESA/NASA SOHO

    Onboard SOHO is an instrument named GOLF (Global Oscillations at Low Frequencies) – designed to search for millimetre-sized gravity, or g-mode, oscillations on the Sun’s surface (the photosphere). Evidence for these g-modes has, however, proven elusive – convection of energy within the Sun disrupts the oscillations, and the Sun’s convective layer exists in its outer third. If solar g-modes exist then they do so deep within the Sun’s radiative core.

    A team led by Eric Fossat of the Université Côte d’Azur in France has therefore taken a different tack. The researchers realized that acoustic pressure, or p-mode, oscillations that penetrate all the way through to the core – which Fossat dubs “solar music” – could be used as a probe for g-mode oscillations. Assessing over 16 years’ worth of observations by GOLF, Fossat’s team has found that p-modes passing through the solar core are modulated by the g-modes that reverberate there, slightly altering the spacing between the p-modes.

    Fossat describes this discovery as “a fantastic result”, in terms of what g-modes can tell us about the solar interior. The properties of the g-mode oscillations depend strongly on the structure and conditions within the Sun’s core, including the ratio of hydrogen to helium, and the period of the g-modes indicate that the Sun’s core rotates approximately once per week. This is around four times faster than the Sun’s outer layers, which rotate once every 25 days at the equator and once every 35 days at the poles.

    Diving into noise

    Not everyone is convinced by the results. Jeff Kuhn of the University of Hawaii describes the findings as “interesting”, but warns that independent verification is required.

    “Over the last 30 years there have been several claims for detecting g-modes, but none have been confirmed,” Kuhn told physicsworld.com. “In their defence, [Fossat’s researchers] have tried several different tests of the GOLF data that give them confidence, but they are diving far into the noise to extract this signal.” He thinks that long-term ground-based measurements of some p-mode frequencies should also contain the signal and confirm Fossat’s findings further.

    If the results presented in Astronomy & Astrophysics can be verified, then Kuhn is excited about what a faster spinning core could mean for the Sun. “It could pose some trouble for our basic understanding of the solar interior,” he says. When stars are born, they are spinning fast but over time their stellar winds rob their outer layers of angular momentum, slowing them down. But Fossat suggests that conceivably their cores could somehow retain their original spin rate.

    Solar links under scrutiny

    Turning attention from the Sun’s core to its outer layers reveals another mystery. The energy generated by nuclear reactions in the Sun’s core ultimately powers the activity in the Sun’s outer layers, including the corona. But the corona is more than a million degrees hotter than the layers of the chromosphere and photosphere below it. The source of this coronal heating is unknown, but a new paper published in Nature Communications has found a link between the elemental composition of the corona, which features a broad spectrum of atomic nuclei including iron and neon, and the Sun’s 11 year cycle of magnetic activity.

    Observations made by SDO between 2010 (when the Sun was near solar minimum) and 2014 (when its activity peaked) revealed that when at minimum, the corona’s composition is dominated by processes of the quiet Sun. However, when at maximum the corona’s composition is instead controlled by some unidentified process that takes place around the active regions of sunspots.

    That the composition of the corona is not linked to a fixed property of the Sun (such as its rotation) but is instead connected to a variable property, could “prompt a new way of thinking about the coronal heating problem,” says David Brooks of George Mason University, USA, who is lead author on the paper. This is because the way in which elements are transported into the corona is thought to be closely related to how the corona is being heated.

    Quest for consensus

    Many explanations for the corona’s high temperature have been proposed, ranging from magnetic reconnection to fountain-like spicules, and magnetic Alfvén waves to nanoflares, but none have yet managed to win over a consensus of solar physicists.

    “If there’s a model that explains everything – the origins of the solar wind, coronal heating and the observed preferential transport – then that would be a very strong candidate,” says Brooks. The discovery that the elemental abundances vary with the magnetic cycle is therefore a new diagnostic against which to test models of coronal heating.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    PhysicsWorld is a publication of the Institute of Physics. The Institute of Physics is a leading scientific society. We are a charitable organisation with a worldwide membership of more than 50,000, working together to advance physics education, research and application.

    We engage with policymakers and the general public to develop awareness and understanding of the value of physics and, through IOP Publishing, we are world leaders in professional scientific communications.
    IOP Institute of Physics

     
  • richardmitnick 10:11 am on August 11, 2017 Permalink | Reply
    Tags: , , Modulating semiconductors, , Physics   

    From BNL: “Scientists Find New Method to Control Electronic Properties of Nanocrystals” 

    Brookhaven Lab

    August 10, 2017
    Stephanie Kossman

    1
    From Left to Right: XPD beamline scientist Sanjit Ghose, postdoctoral researcher Anna Plonka, and Brookhaven Chemist Anatoly Frenkel.

    Researchers from The Hebrew University of Jerusalem, Stony Brook University, and the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory have discovered new effects of an important method for modulating semiconductors. The method, which works by creating open spaces or “vacancies” in a material’s structure, enables scientists to tune the electronic properties of semiconductor nanocrystals (SCNCs)—semiconductor particles that are smaller than 100 nanometers. This finding will advance the development of new technologies like smart windows, which can change opaqueness on demand.

    Scientists use a technique called “chemical doping” to control the electronic properties of semiconductors. In this process, chemical impurities—atoms from different materials—are added to a semiconductor in order to alter its electrical conductivity. Though it is possible to dope SCNCs, it is very difficult due to their tiny size. The amount of impurities added during chemical doping is so small that in order to dope a nanocrystal properly, no more than a few atoms can be added to the crystal. Nanocrystals also tend to expel impurities, further complicating the doping process.

    Seeking to control the electronic properties of SCNCs more easily, researchers studied a technique called vacancy formation. In this method, impurities are not added to the semiconductor; instead, vacancies in its structure are formed by oxidation-reduction (redox) reactions, a type of chemical reaction where electrons are transferred between two materials. During this transfer, a type of doping occurs as missing electrons, called holes, become free to move throughout the structure of the crystal, significantly altering the electrical conductivity of the SCNC.

    “We have also identified size effects in the efficiency of the vacancy formation doping reaction,” said Uri Banin, a nanotechnologist from the Hebrew University of Jerusalem. “Vacancy formation is actually more efficient in larger SCNCs.”

    In this study, the researchers investigated a redox reaction between copper sulfide nanocrystals (the semiconductor) and iodine, a chemical introduced in order to influence the redox reaction to occur.

    2
    (Top) The removal of copper from copper sulfide nanocrystals and the growth of copper iodine on nanocrystal facets is depicted by results from XAFS; (Bottom left) Larger nanocrystals are doped more efficiently by vacancy formation; (Right) Vacancy formation is observed by XRD.

    “If you reduce copper sulfide, you will pull out copper from the nanocrystal, generating vacancies and therefore holes,” said Anatoly Frenkel, a chemist at Brookhaven National Laboratory holding a joint appointment with Stony Brook University, and the lead Brookhaven researcher on this study.

    The researchers used the x-ray powder diffraction (XPD) beamline at the National Synchrotron Light Source II (NSLS-II)—a DOE Office of Science User Facility—to study the structure of copper sulfide during the redox reaction.

    BNL NSLS-II


    BNL NSLS II

    By shining ultra-bright x-rays onto their samples, the researchers are able to determine the amount of copper that is pulled out during the redox reaction.

    Based on their observations at NSLS-II, the team confirmed that adding more iodine to the system caused more copper to be released and more vacancies to form. This established that vacancy formation is a useful technique for tuning the electronic properties of SCNCs.

    Still, the researchers needed to find out what exactly was happening to copper when it left the nanocrystal. Understanding how copper behaves after the redox reaction is crucial for implementing this technique into smart window technology.

    “If copper uncontrollably disappears, we can’t pull it back into the system,” Frenkel said. “But suppose the copper that is taken out of the crystal is hovering around, ready to go back in. By using the reverse process, we can put it back into the system, and we can make a device that would be easy to switch from one state to the other. For example, you would be able to change the transparency of a window on demand, depending on the time of day or your mood.”

    To understand what was happening to copper, the researchers used x-ray absorption fine structure (XAFS) spectroscopy at the Advanced Photon Source (APS)—also a DOE Office of Science User Facility—at Argonne National Laboratory. This technique allows the researchers to study the extremely small copper complexes that x-ray diffraction cannot detect. XAFS revealed that copper was combining with iodine to form copper iodine, a positive result that indicated copper could be put back into the nanocrystal and that the researchers have full control of the electronic properties.

    The researchers say the next step is to study materials in real-time during redox reactions using NSLS-II.

    This study was supported by the National Science Foundation, the US-Israel Binational Science Foundation, and Northwestern University. DOE’s Office of Science also supports operations at NSLS-II and APS.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition
    BNL Campus

    One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world. Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.
    i1

     
  • richardmitnick 7:58 am on August 10, 2017 Permalink | Reply
    Tags: , , , , Physics, ,   

    From ScienceNews: “Neutrino experiment may hint at why matter rules the universe” 

    ScienceNews bloc

    ScienceNews

    1
    NEUTRINO CLUES The T2K experiment found clues that neutrinos may behave differently than their antimatter partners. In a possible sighting of an electron neutrino at the Super-Kamiokande detector in Hida, Japan (shown), colored spots represent sensors that observed light from the interacting neutrino. Kamioka Observatory/ICRR/The University of Tokyo

    A new study hints that neutrinos might behave differently than their antimatter counterparts. The result amplifies scientists’ suspicions that the lightweight elementary particles could help explain why the universe has much more matter than antimatter.

    In the Big Bang, 13.8 billion years ago, matter and antimatter were created in equal amounts. To tip that balance to the universe’s current, matter-dominated state, matter and antimatter must behave differently, a concept known as CP, or “charge parity,” violation.

    In neutrinos, which come in three types — electron, muon and tau — CP violation can be measured by observing how neutrinos oscillate, or change from one type to another. Researchers with the T2K experiment found that muon neutrinos morphed into electron neutrinos more often than expected, while muon antineutrinos became electron antineutrinos less often. That suggests that the neutrinos were violating CP, the researchers concluded August 4 at a colloquium at the High Energy Accelerator Research Organization, KEK, in Tsukuba, Japan.

    T2K scientists had previously presented a weaker hint [Physical Review Letters]of CP violation. The new result is based on about twice as much data, but the evidence is still not definitive. In physicist parlance, it is a “two sigma” measurement, an indicator of how statistically strong the evidence is. Physicists usually require five sigma to claim a discovery.

    Even three sigma is still far away — T2K could reach that milestone by 2026. A future experiment, DUNE, now under construction at the Sanford Underground Research Laboratory in Lead, S.D., may reach five sigma.

    FNAL LBNF/DUNE from FNAL to SURF, Lead, South Dakota, USA


    FNAL DUNE Argon tank at SURF


    Surf-Dune/LBNF Caverns at Sanford



    SURF building in Lead SD USA

    It is worth being patient, says physicist Chang Kee Jung of Stony Brook University in New York, who is a member of the T2K collaboration. “We are dealing with really profound problems.”

    See the full article here .

    Science News is edited for an educated readership of professionals, scientists and other science enthusiasts. Written by a staff of experienced science journalists, it treats science as news, reporting accurately and placing findings in perspective. Science News and its writers have won many awards for their work; here’s a list of many of them.

    Published since 1922, the biweekly print publication reaches about 90,000 dedicated subscribers and is available via the Science News app on Android, Apple and Kindle Fire devices. Updated continuously online, the Science News website attracted over 12 million unique online viewers in 2016.

    Science News is published by the Society for Science & the Public, a nonprofit 501(c) (3) organization dedicated to the public engagement in scientific research and education.

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

     
  • richardmitnick 3:30 pm on August 4, 2017 Permalink | Reply
    Tags: , , , , , , , Physics,   

    From Symmetry: “The birth of a black hole, live” 09/09/15 

    Symmetry Mag

    Symmetry

    09/09/15 [this is old, but a lot of sites are featuring it again.]
    Lauren Biron

    1
    NASA/CXC/M.Weiss

    Scientists hope to use neutrino experiments to watch a black hole form.

    Black holes fascinate us. We easily conjure up images of them swallowing spaceships, but we know very little about these strange objects. In fact, we’ve never even seen a black hole form. Scientists on neutrino experiments such as the upcoming Deep Underground Neutrino Experiment hope to change that.

    FNAL LBNF/DUNE from FNAL to SURF, Lead, South Dakota, USA


    FNAL DUNE Argon tank at SURF


    Surf-Dune/LBNF Caverns at Sanford



    SURF building in Lead SD USA

    “You’ve got to be a bit lucky,” says Mark Thomson, DUNE co-spokesperson. “But it would be one of the major discoveries in science. It would be absolutely incredible.”

    Black holes are sometimes born when a massive star, typically more than eight times the mass of our own sun, collapses. But there are a lot of questions about what exactly happens during the process: How often do these collapsing stars give rise to black holes? When in the collapse does the black hole actually develop?

    What scientists do know is that deep in the dense core of the star, protons and electrons are squeezed together to form neutrons, sending ghostly particles called neutrinos streaming out. Matter falls inward. In the textbook case, matter rebounds and erupts, leaving a neutron star. But sometimes, the supernova fails, and there’s no explosion; instead, a black hole is born.

    DUNE’s gigantic detectors, filled with liquid argon, will sit a mile below the surface in a repurposed goldmine. While much of their time will be spent looking for neutrinos sent from Fermi National Accelerator Laboratory 800 miles away, the detectors will also have the rare ability to pick up a core collapse in our Milky Way galaxy – whether or not that leads to a new black hole.

    The only supernova ever recorded by neutrino detectors occurred in in 1987, when scientists saw a total of 19 neutrinos. Scientists still don’t know if that supernova formed a black hole or a neutron star—there simply wasn’t enough data. Thomson says that if a supernova goes off nearby, DUNE could see up to 10,000 neutrinos.

    DUNE will look for a particular signature in the neutrinos picked up by the detector. It’s predicted that a black hole will form relatively early in a supernova. Neutrinos will be able to leave the collapse in great numbers until the black hole emerges, trapping everything—including light and neutrinos—in its grasp. In data terms, that means you’d get a big burst of neutrinos with a sudden cutoff.

    Neutrinos come in three types, called flavors: electron, muon and tau. When a star explodes, it emits all the various types of neutrinos, as well as their antiparticles.

    They’re hard to catch. These neutrinos arrive with 100 times less energy than those arriving from an accelerator for experiments, which makes them less likely to interact in a detector.

    Most of the currently running, large particle detectors capable of seeing supernova neutrinos are best at detecting electron antineutrinos—and not great at detecting their matter equivalents, electron neutrinos.

    “It would be a tragedy to not be ready to detect the neutrinos in full enough detail to answer key questions,” says John Beacom, director of the Center for Cosmology and Astroparticle Physics at The Ohio State University.

    Luckily, DUNE is unique. “The only one that is sensitive to a huge slug of electron neutrinos is DUNE, and that’s a function of using argon [as the detector fluid],” says Kate Scholberg, professor of physics at Duke University.

    It will take more than just DUNE to get the whole picture, though. Getting an entire suite of large, powerful detectors of different types up and running is the best way to figure out the lives of black holes, Beacom says.

    There is a big scintillator detector, JUNO, in the works in China, and plans for a huge water-based detector, Hyper-K, in Japan.

    JUNO Neutrino detector, at Kaiping, Jiangmen in Southern China

    Hyper-Kamiokande, a neutrino physics laboratory located underground in the Mozumi Mine of the Kamioka Mining and Smelting Co. near the Kamioka section of the city of Hida in Gifu Prefecture, Japan.

    Gravitational wave detectors such as LIGO could pick up additional information about the density of matter and what’s happening in the collapse.


    Caltech/MIT Advanced aLigo Hanford, WA, USA installation


    Caltech/MIT Advanced aLigo detector installation Livingston, LA, USA

    Cornell SXS, the Simulating eXtreme Spacetimes (SXS) project


    Gravitational waves. Credit: MPI for Gravitational Physics/W.Benger-Zib

    ESA/eLISA the future of gravitational wave research

    “My dream is to have a supernova with JUNO, Hyper-K and DUNE all online,” Scholberg says. “It would certainly make my decade.”

    The rate at which neutrinos arrive after a supernova will tell scientists about what’s happening at the center of a core collapse—but it will also provide information about the mysterious neutrino, including how they interact with each other and potential insights as to how much the tiny particles actually weigh.

    Within the next three years, the rapidly growing DUNE collaboration will build and begin testing a prototype of the 40,000-ton liquid argon detector. This 400-ton version will be the second-largest liquid-argon experiment ever built to date. It is scheduled for testing at CERN starting in 2018.

    DUNE is scheduled to start installing the first of its four detectors in the Sanford Underground Research Facility in 2021.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    Symmetry is a joint Fermilab/SLAC publication.


     
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