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  • richardmitnick 9:06 am on July 26, 2017 Permalink | Reply
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    From UCLA Newsroom: “Brain activity test detects autism severity, UCLA study finds” 


    UCLA Newsrooom

    July 25, 2017
    Sarah C.P. Williams

    UCLA RESEARCH ALERT

    FINDINGS

    UCLA researchers have discovered that children with autism have a tell-tale difference on brain tests compared with other children. Specifically, the researchers found that the lower a child’s peak alpha frequency — a number reflecting the frequency of certain brain waves — the lower their non-verbal IQ was. This is the first study to highlight peak alpha frequency as a promising biomarker to not only differentiate children with autism from typically developing children, but also to detect the variability in cognitive function among children with autism.

    BACKGROUND

    Autism spectrum disorder affects an estimated one in 68 children in the United States, causing a wide range of symptoms. While some individuals with the disorder have average or above-average reasoning, memory, attention and language skills, others have intellectual disabilities. Researchers have worked to understand the root of these cognitive differences in the brain and why autism spectrum disorder symptoms are so diverse.

    An electroencephalogram, or EEG, is a test that detects electrical activity in a person’s brain using small electrodes that are placed on the scalp. It measures different aspects of brain activity including peak alpha frequency, which can be detected using a single electrode in as little as 40 seconds and has previously been linked to cognition in healthy individuals.

    METHOD

    The researchers performed EEGs on 97 children ages 2 to 11; 59 had diagnoses of autism spectrum disorder and 38 did not have the disorder. The EEGs were taken while the children were awake and relaxed in dark, quiet rooms. Correlations among age, verbal IQ, non-verbal IQ and peak alpha frequency were then studied.

    IMPACT

    The discovery that peak alpha frequency relates directly to non-verbal IQ in children with the disorder suggests a link between the brain’s functioning and the severity of the condition. Moreover, it means that researchers may be able to use the test as a biomarker in the future, to help study whether an autism treatment is effective in restoring peak alpha frequency to normal levels, for instance.

    More work is needed to understand whether peak alpha frequency can be used to predict the development of autism spectrum disorder in young children before symptoms emerge.

    AUTHORS

    The authors of the study are Shafali Spurling Jeste, UCLA associate professor in psychiatry, neurology and pediatrics and a lead investigator of the UCLA Center for Autism Research and Treatment; Abigail Dickinson and Charlotte DiStefano, postdoctoral fellows at the UCLA Center for Autism Research and Treatment; and Damla Senturk, associate professor of biostatistics at UCLA.

    JOURNAL

    The study was published online in the European Journal of Neuroscience.

    FUNDING

    The study was funded by Autism Speaks (Meixner Postdoctoral Fellowship in Translational Research), the National Institutes of Mental Health (K23MH094517), the National Institute of General Medical Sciences (R01 GM111378-01A1) and the National Institute of Health (ACE 2P50HD055784-06).

    See the full article here .

    Please help promote STEM in your local schools.

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    UC LA Campus

    For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

    We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

    This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.

     
  • richardmitnick 8:43 am on July 26, 2017 Permalink | Reply
    Tags: , , Dr. Emeran Mayer, , , Understanding the constant dialogue that goes on between our gut and our brain   

    From UCLA Newsroom: “Understanding the constant dialogue that goes on between our gut and our brain” 


    UCLA Newsrooom

    July 25, 2017
    Dan Gordon

    1
    Dr. Emeran Mayer has built a scientific case for the inextricable link between the brain and the gut, and their influence on our emotional and physical states. Ann Johansson/UCLA.

    Just past midnight on Sept. 26, 1983, Lt. Colonel Stanislav Petrov, a member of the Soviet Air Defense Forces serving as the command-center duty officer for a nuclear early-warning system, faced a decision with unimaginable consequences.

    Cold War tensions were running hot. The Soviet Union had recently shot down Korean Air Lines Flight 007, killing all 269 passengers and crew aboard the Boeing 747. The Soviets claimed the plane was on a spy mission and represented a deliberate provocation by the United States.

    Now, in a bunker outside of Moscow where Petrov was stationed, alarm bells blared as Soviet satellites detected five U.S. ballistic missiles heading toward the USSR. Was this a real nuclear attack warranting retaliation? Or was it a false alarm? Gazing at a screen that flashed “launch” “launch” “launch,” Petrov had only minutes to decide.

    Thirty years later, Petrov reflected on his fateful decision to ignore the signal coming from the satellite detection system — which, of course, had turned out to be erroneous. But at the time, when he couldn’t know that for sure, Petrov said he ultimately made the decision based on “a funny feeling in my gut.”

    In his book The Mind-Gut Connection: How the Hidden Conversation Within Our Bodies Impacts Our Mood, Our Choices, and Our Overall Health (Harper Collins, 2016), Dr. Emeran Mayer retells Petrov’s story, and he notes how many historic and present-day decision-makers have cited unspecified feelings in their gut as tipping the balance on a difficult call.

    To many of us, these “gut feelings” leading to “gut decisions” represent instincts with no basis in reasoned thought. But Dr. Mayer, professor of medicine, physiology and psychiatry and biobehavioral sciences and director of the UCLA Oppenheimer Center for Neurobiology of Stress and Resilience, has other ideas. Acting on his own inclinations developed as a medical student, he has spent the last 40 years building a scientific case for the inextricable link between the brain and the gut, often calling into question the conventional medical wisdom.

    “The gut,” Dr. Mayer says, “converses with the brain like no other organ. When people talk about going with their gut feelings on an important decision, what they’re referring to is an intuitive knowledge based on the close relationship between our emotions and the sensations and feelings in the gastrointestinal (GI) tract.”

    These gut sensations go in both directions. “When you eat too much or have certain fatty foods, the changes in your gut can affect your mental state,” Dr. Mayer notes. “And when you feel ‘butterflies’ or a rumbling in your stomach when you’re nervous, or knots in your stomach when you’re angry, your mental state is affecting your gut.”

    2
    The gut and the brain are closely linked through bidirectional signaling pathways that include nerves, hormones and inflammatory molecules. Illustration by Jon Lee.

    Dr. Mayer and the growing number of colleagues at UCLA and around the world who are interested in the mind-gut connection have been buoyed by the emerging evidence coming from studies of the gut microbiome — the 100-trillion-or-so bacteria and other microbes that make their home in our intestines. Research (mostly in the laboratory, but some in humans) suggests that emotions can affect the gut microbiota, and that, conversely, certain gut microbes can be mind-altering.

    Yes, the gut has its essential roles to play in digestion and metabolism. But as Dr. Mayer suggested in an interview with Scientific American in 2010: “The system is way too complicated to have evolved only to make sure things move out of your colon.”

    Dr. Mayer is convinced that the brain-gut axis isn’t a linear system, as it is often still viewed, but a circular-feedback loop operating through multiple communication channels. One of the most common channels is via activation of the vagus nerve, which extends from the gut lining to the brain stem. But interactions also can occur between the brain and the immune system (the gut hosts the majority of the body’s immune cells) and between the brain and the endocrine system. When the communication channels go awry for one of a variety of reasons — including poor diet, stress or illness — the result can be physical-health problems such as digestive disorders and obesity or mental-health issues such as anxiety or depression. It’s no coincidence, Dr. Mayer notes, that most patients with anxiety or depression also have abnormal gastrointestinal function.

    Dr. Mayer’s influence in shedding light on the mind-gut connection extends well beyond his own work; he has consulted with researchers looking at the relationship from a variety of vantage points. “Emeran has a unique ability to communicate across different levels of analysis — from the cellular to the physiological to the psychological to the behavioral,” says Nancy Zucker, director of the Center for Eating Disorders at Duke University. “That enables researchers to better see the clinical and translational implications of our studies.”

    Zucker has sought Dr. Mayer’s counsel on studies of the impact of gut-brain interactions on people with eating disorders and has collaborated with his group in studies of patients with anorexia nervosa. She is pursuing the hypothesis that a hypersensitivity to gut sensations fuels the disorder. “The widely accepted narrative is that these are individuals with a biological vulnerability, and the environment brings it out,” Zucker says. “We believe that this vulnerability starts below the neck, and that it is neurological.”

    Well before the current “decade of the microbiome,” Dr. Michael Gershon broke new ground with his book The Second Brain (Harper, 1998), referring to the collection of approximately 100 million neurons in the gut that constitute the enteric nervous system and act both independently and interdependently with the brain in our head. While it’s no help in matters of philosophy, poetry and other forms of deep thought, Dr. Gershon noted, this second brain and how it interacts with the first one is a key factor in our physical and mental well-being.

    The gut remains an underappreciated organ even by many scientists and physicians — perhaps because it isn’t pleasant to look at or think about, suggests Dr. Gershon, who continues to serve as chairman of the Department of Anatomy and Cell Biology at Columbia University.

    “What Emeran Mayer and others are finding is that there is a whole world of microorganisms that live in the gut,” he says, “and that they are not just evil bacteria but are companions in life.”

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    UC LA Campus

    For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

    We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

    This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.

     
  • richardmitnick 5:57 pm on July 25, 2017 Permalink | Reply
    Tags: , , ,   

    From U Wisconsin IceCube: “Improved measurements of neutrino oscillations with IceCube” 

    icecube
    U Wisconsin IceCube South Pole Neutrino Observatory

    25 Jul 2017
    Sílvia Bravo

    A denser and smaller array of sensors at the bottom of the IceCube Neutrino Observatory, the DeepCore detector, enables the detection of neutrinos produced by the interaction of cosmic rays with the atmosphere down to energies of only a few GeVs. On their way to IceCube, many of the neutrinos produced in the Northern Hemisphere will morph into other neutrinos due to a well-known quantum effect: neutrino oscillations

    n 2013, IceCube reported its first measurement of the neutrino oscillation parameters. This was the first time that neutrino oscillations were measured with precision at energies between 20 and 100 GeV. The results were compatible with those from devoted neutrino experiments, but now the model was tested at higher energies, although uncertainties were still larger. A year later, the collaboration presented a second analysis with three years of data that improved the precision by a factor of ten. This week, the IceCube Collaboration presents a new measurement of the oscillation parameters that for the first time is competitive with the best measurements to date. These results have just been submitted to Physical Review Letters.

    1
    The oscillations parameters measured in this work compared to best results from other experiments. The cross marks the IceCube best-fit point. The 90% confidence level contours were calculated using the approach of Feldman and Cousins. The outer plots show the results of the 1-D projections of the 68% confidence level contours. Credit: IceCube Collaboration

    Long-baseline experiments, such as T2K or NOvA, observe much lower energy events.

    T2K Experiment


    T2K map

    FNAL NOvA Near Detector


    FNAL/NOvA experiment map

    Understanding neutrino oscillations at higher energies tests systematic uncertainties but also places constraints on different new physics models in the neutrino sector.

    The current measurement has improved the selection of neutrino events by a factor ten. The IceCube sensors immediately surrounding DeepCore are used as a veto against muons produced in the same atmospheric cosmic ray interactions, keeping only events that start inside the DeepCore instrumented volume.

    “The event reconstruction is a significant improvement of this analysis,” explains João Pedro Athayde Marcondes de André, an IceCube researcher at Michigan State University (MSU) and a coleader of this analysis. “We now take into account the properties of the ice to reconstruct all types of events, even those with a substantial energy deposition at the beginning of the event, where the interaction of the incoming neutrino with the Antarctic ice takes place,” adds A. M. de André.

    “IceCube is the first experiment using atmospheric neutrinos to measure the oscillation parameters with a similar precision to long-baseline experiments,” says Joshua Hignight, also an IceCube researcher at MSU and a coleader of this work. “But we measure them in a different energy range and with different baselines,” states Hignight.

    The best fit oscillation parameters point to a maximal mixing scenario, in agreement with results from the T2K experiment and in tension with measurements from the NOvA experiment. In the maximal mixing scenario, one of the neutrino quantum states is a precise equal mix of two different flavor neutrinos. Although this could be just a coincidence, it could also be a hint to new physics.

    See the full article here .

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    ICECUBE neutrino detector

    IceCube is a particle detector at the South Pole that records the interactions of a nearly massless sub-atomic particle called the neutrino. IceCube searches for neutrinos from the most violent astrophysical sources: events like exploding stars, gamma ray bursts, and cataclysmic phenomena involving black holes and neutron stars. The IceCube telescope is a powerful tool to search for dark matter, and could reveal the new physical processes associated with the enigmatic origin of the highest energy particles in nature. In addition, exploring the background of neutrinos produced in the atmosphere, IceCube studies the neutrinos themselves; their energies far exceed those produced by accelerator beams. IceCube is the world’s largest neutrino detector, encompassing a cubic kilometer of ice.

     
  • richardmitnick 3:25 pm on July 25, 2017 Permalink | Reply
    Tags: , All of the scenarios envision the ESS operating with 2 MW of power in 2023, , Helps scientists for example to locate hydrogen which with only one electron is a more elusive target for x-rays, Like x-rays beams of neutrons are a way for scientists to explore the atomic structure of materials, Neutrons scatter off atomic nuclei, , , Rising costs hamper mega–neutron beam facility   

    From AAAS: “Rising costs hamper mega–neutron beam facility” 

    AAAS

    AAAS

    Jul. 24, 2017
    Edwin Cartlidge

    1
    The European Spallation Source, under construction in Lund, Sweden, may not reach its design power of 5 megawatts. Perry Nordeng/ESS.

    The world’s most powerful source of neutron beams will be less than half as powerful as planned when the facility begins scientific experiments in 2023. The European Spallation Source (ESS), under construction in Lund, Sweden, was designed to reach 5 megawatts (MW), but ballooning costs means that it will only achieve 2 MW in 6 years’ time—a reduced level that will likely limit the range of scientific studies it can carry out.

    Although the ESS council, the project’s main decision-making body, is considering plans that would boost power to 5 MW by 2025, some scientists fear that the facility will remain stuck at 2 MW for good. “There are some people with persuasive voices who say you don’t need 5 MW,” says Colin Carlile, a physicist at Uppsala University in Sweden and former ESS director. “But theirs are siren voices. It would be tragic if that happens.”

    Like x-rays, beams of neutrons are a way for scientists to explore the atomic structure of materials. But where x-rays scatter off the cloud of electrons surrounding an atom, neutrons scatter off atomic nuclei. That capability helps scientists, for example, to locate hydrogen, which, with only one electron, is a more elusive target for x-rays. Neutron beams can also differentiate between nuclei of different isotopes. And, because neutrons carry a spin, they can reveal the magnetic properties of the material in question.

    Most neutron sources are nuclear reactors that generate neutrons through fission. But in recent years scientists have increasingly turned to spallation sources, in which an accelerated beam of protons breaks apart the nuclei of atoms in a solid target, stripping off neutrons that are then channeled into beams and directed toward instruments used to carry out experiments. A higher power beam leads to a greater flux of neutrons, enabling greater spatial and temporal resolution and the study of small samples, such as proteins.

    The ESS was proposed back in the late 1980s as a way to maintain Europe’s lead [Science] in this field, given planned 1=MW-caliber facilities in the United States and Japan. The imminent start of the ESS should also help counter growing worries about a “neutron drought” [Science] in Europe, as older neutron sources close. Building work on the ESS eventually began in 2014, after the project’s 15 partner countries agreed to foot the €1.84 billion construction bill. Plans at that point called for first neutrons in 2019, full 5-MW beam power for the first user experiments in 2023, with 16 of the instruments then available 2 years after that and the full complement of 22 instruments “a few years later,” according to ESS Director General John Womersley.

    Those deadlines are now slipping owing to the project’s “initial operations phase,” which runs from 2019 to 2025, costing at least €150 million more than a €850 million forecast in 2014. At a meeting in June, the ESS council began evaluating scenarios to bring these costs down. Cost-cutting options include postponing the purchase of equipment needed to boost proton power to 5 MW and slowing the speed at which instruments reach full specification.

    All of the scenarios envision the ESS operating with 2 MW of power in 2023 in order to guarantee what Womersley describes as “world leading performance” when experiments start up. But whereas one scenario delivers 5 MW by 2025, another foresees no rise in power by then. Similarly, although all the plans require 15 instruments to be installed by 2025, there are differences over how many of the additional seven will be constructed by that date. “We are retaining the project’s ultimate goals but changing the speed at which we achieve them,” he says.

    Michael Preuss, a materials scientist at the University of Manchester in the United Kingdom and chair of the ESS science advisory committee, describes the delay in full power as “a very sensible thing to do.” He would prefer to expand the number of instruments rather than boosting power early on. In any case, he maintains, improvements to the design of the machine’s moderators—devices needed to slow neutrons down to the speeds that make them useful for research—will yield a neutron flux that is “almost as high” at 2 MW as it would have been at 5 MW.

    Carlile says the project is going as he “would expect” for a large scientific facility built mainly with in-kind contributions. But he doesn’t think that progress with the moderators will compensate for the lower initial power, and he is worried that the cutbacks in power and instruments will be costly for European neutron science.

    The ESS council plans to decide on a preferred scenario before the end of this year so that member nations can then agree to their shares of that budget in 2018.

    See the full article here .

    The American Association for the Advancement of Science is an international non-profit organization dedicated to advancing science for the benefit of all people.

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  • richardmitnick 3:00 pm on July 25, 2017 Permalink | Reply
    Tags: , Allows for more fishing, , Australia is fringed by some of the richest marine ecosystems in the world, Australian government to roll back marine protections, Australian marine reserves reduced by government,   

    From AAAS: “Australian government to roll back marine protections 

    AAAS

    AAAS

    Jul. 24, 2017
    April Reese

    Draft plan leaves scientists seething.

    1
    Fishing camps in western Australia’s Houtman Abrolhos Islands. Controversial new marine reserve plan seeks to balance habitat protection with sustainable fishing. Bill Bachman/Alamy Stock Photo.

    Five years after the Australian government created one of the world’s largest networks of marine reserves, it has unveiled a heavily revised management blueprint that would curtail conservation. Some scientists are assailing the plan as deeply flawed. “I suppose you could say it’s an insult to the science community. It’s not evidence-based,” says David Booth, a marine ecologist at the University of Technology in Sydney, Australia.

    Australia is fringed by some of the richest marine ecosystems in the world. Recognizing the need to protect those resources, in 2012, after years of input from scientists and the public, the Australian government strung together a necklace of marine reserves encircling the continent. But following elections a few months later, the new conservative government commissioned an independent review to gather more public input. The draft plan, released on Friday, retains the 2012 plan’s boundaries but scales back protections in some areas to allow for more fishing.

    The proposal, which will undergo a 60-day public review period before heading to Parliament, which is expected to approve the plan, covers 44 marine reserves encompassing 36% of Australia’s exclusive economic zone—the wide ring of ocean from about 5 kilometers offshore to 370 kilometers out. In maps showing which activities will be allowed where in the reserves, large swaths of no-take “green” zones designated in 2012—areas in which no fishing or mining would be allowed—have been converted to “habitat protection zones,” where sea floor–ravaging activities such as trawling are barred but other types of fishing are permitted. Under the new plan, only 20% of the reserves would be green zones and more permissive “yellow” habitat protection zones would increase from 24% to 43%.

    2
    G. Grullón/Science

    Many marine scientists are dismayed. “They’ve nearly halved the level of protection,” says marine ecologist Jessica Meeuwig, director of the University of Western Australia’s Centre for Marine Futures in Perth. “It’s very demoralizing to the scientists who’ve done so much hard work,” Booth adds. “You would not believe the amount of work that’s been put into establishing these places. Then suddenly it all comes off the table.”

    The massive Coral Sea marine reserve, which buffets the Great Barrier Reef along Australia’s northeast coast, faces the biggest conservation rollback under the plan. About 76% of its sprawling 98-million-hectare expanse would be open to fishing, up from 46%. That would aid the tuna industry, according to the environment department. “They’ve saved the tuna fishery $4 million a year,” Meeuwig says. “So in order to save .03% of fishing revenue, we’ve scuppered what could be the single most important marine protected area in the Pacific.”

    See the full article here .

    The American Association for the Advancement of Science is an international non-profit organization dedicated to advancing science for the benefit of all people.

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  • richardmitnick 2:25 pm on July 25, 2017 Permalink | Reply
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    From astrobites: “Dark Matter in the Milky Way: ‘A Matter of Perspective’ “ 

    Astrobites bloc

    Astrobites

    Jul 25, 2017
    Nora Shipp

    Title: The core-cusp problem: A matter of perspective
    Authors: Anna Genina, Alejandro Benitez-Llambay, Carlos S. Frenk, Shaun Cole, Azadeh Fattahi, Julio F. Navarro, Kyle A. Oman, Till Sawala, Tom Theuns
    First Author’s Institution: Institute for Computational Cosmology,University, UK

    Status: Submitted to the Monthly Notices of the Royal Astronomical Society, Open Access

    Dark matter dominates the Universe around us, far exceeding the amount of everyday baryonic matter that makes up humans, the Earth, and the entire visible Milky Way. Our galaxy is embedded in an invisible cloud of dark matter, which contains smaller dark matter clouds that orbit around us like satellites. These satellites do not contain big spiral galaxies like the Milky Way and, although they may contain smaller galaxies, they are made up of almost entirely dark matter, which means that they are very sensitive to the precise nature of the dark matter particle.

    Today’s paper investigates whether two of the Milky Way’s largest satellite galaxies (Fornax and Sculptor, Figure 1) conflict with the leading theory of Cold Dark Matter (CDM), potentially requiring a complete reconsideration of our understanding of the evolution of the Universe.

    2
    Projected density plot of a redshift {\displaystyle z=2.5} dark matter halo from a cosmological N-body simulation. The visible part of the galaxy (not shown in the image) lies at the dense centre of the halo and has a diameter of roughly 20 kiloparsecs. There are also many satellite galaxies, each with its own subhalo which is visible as a region of high dark matter density in the image. http://en.wikipedia.org/wiki/User:Cosmo0

    Don’t get too excited, though. I will break the suspense and say that, as usual, the answer is “not yet” – we don’t know enough about these mini galaxies to throw away CDM. There is still a lot of work to be done if we want to break this paradigm.

    1
    Figure 1. The Fornax (left) and Sculptor (right) galaxies. (Source: ESO)

    See the full article here .

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    What do we do?

    Astrobites is a daily astrophysical literature journal written by graduate students in astronomy. Our goal is to present one interesting paper per day in a brief format that is accessible to undergraduate students in the physical sciences who are interested in active research.
    Why read Astrobites?

    Reading a technical paper from an unfamiliar subfield is intimidating. It may not be obvious how the techniques used by the researchers really work or what role the new research plays in answering the bigger questions motivating that field, not to mention the obscure jargon! For most people, it takes years for scientific papers to become meaningful.
    Our goal is to solve this problem, one paper at a time. In 5 minutes a day reading Astrobites, you should not only learn about one interesting piece of current work, but also get a peek at the broader picture of research in a new area of astronomy.

     
  • richardmitnick 2:06 pm on July 25, 2017 Permalink | Reply
    Tags: , , , , , , , ,   

    From JPL: “Large, Distant Comets More Common Than Previously Thought” 

    NASA JPL Banner

    JPL-Caltech

    July 25, 2017
    Elizabeth Landau
    Jet Propulsion Laboratory, Pasadena, Calif.
    818-354-6425
    elizabeth.landau@jpl.nasa.gov

    1
    This illustration shows how scientists used data from NASA’s WISE spacecraft to determine the nucleus sizes of comets. They subtracted a model of how dust and gas behave in comets in order to obtain the core size. Credit: NASA/JPL-Caltech.

    2
    An animation of a comet. Credit: NASA/JPL-Caltech.

    Comets that take more than 200 years to make one revolution around the Sun are notoriously difficult to study. Because they spend most of their time far from our area of the solar system, many “long-period comets” will never approach the Sun in a person’s lifetime. In fact, those that travel inward from the Oort Cloud — a group of icy bodies beginning roughly 186 billion miles (300 billion kilometers) away from the Sun — can have periods of thousands or even millions of years.

    Oort Cloud NASA

    NASA’s WISE spacecraft, scanning the entire sky at infrared wavelengths, has delivered new insights about these distant wanderers.

    NASA/WISE Telescope

    Scientists found that there are about seven times more long-period comets measuring at least 0.6 miles (1 kilometer) across than had been predicted previously. They also found that long-period comets are on average up to twice as large as “Jupiter family comets,” whose orbits are shaped by Jupiter’s gravity and have periods of less than 20 years.

    Researchers also observed that in eight months, three to five times as many long-period comets passed by the Sun than had been predicted. The findings are published in The Astronomical Journal.

    “The number of comets speaks to the amount of material left over from the solar system’s formation,” said James Bauer, lead author of the study and now a research professor at the University of Maryland, College Park. “We now know that there are more relatively large chunks of ancient material coming from the Oort Cloud than we thought.”

    The Oort Cloud is too distant to be seen by current telescopes, but is thought to be a spherical distribution of small icy bodies at the outermost edge of the solar system. The density of comets within it is low, so the odds of comets colliding within it are rare. Long-period comets that WISE observed probably got kicked out of the Oort Cloud millions of years ago. The observations were carried out during the spacecraft’s primary mission before it was renamed NEOWISE and reactivated to target near-Earth objects (NEOs).

    “Our study is a rare look at objects perturbed out of the Oort Cloud,” said Amy Mainzer, study co-author based at NASA’s Jet Propulsion Laboratory, Pasadena, California, and principal investigator of the NEOWISE mission. “They are the most pristine examples of what the solar system was like when it formed.”

    Astronomers already had broader estimates of how many long-period and Jupiter family comets are in our solar system, but had no good way of measuring the sizes of long-period comets. That is because a comet has a “coma,” a cloud of gas and dust that appears hazy in images and obscures the cometary nucleus. But by using the WISE data showing the infrared glow of this coma, scientists were able to “subtract” the coma from the overall comet and estimate the nucleus sizes of these comets. The data came from 2010 WISE observations of 95 Jupiter family comets and 56 long-period comets.

    The results reinforce the idea that comets that pass by the Sun more often tend to be smaller than those spending much more time away from the Sun. That is because Jupiter family comets get more heat exposure, which causes volatile substances like water to sublimate and drag away other material from the comet’s surface as well.

    “Our results mean there’s an evolutionary difference between Jupiter family and long-period comets,” Bauer said.

    The existence of so many more long-period comets than predicted suggests that more of them have likely impacted planets, delivering icy materials from the outer reaches of the solar system.

    Researchers also found clustering in the orbits of the long-period comets they studied, suggesting there could have been larger bodies that broke apart to form these groups.

    The results will be important for assessing the likelihood of comets impacting our solar system’s planets, including Earth.

    “Comets travel much faster than asteroids, and some of them are very big,” Mainzer said. “Studies like this will help us define what kind of hazard long-period comets may pose.”

    NASA’s Jet Propulsion Laboratory in Pasadena, California, managed and operated WISE for NASA’s Science Mission Directorate in Washington. The NEOWISE project is funded by the Near Earth Object Observation Program, now part of NASA’s Planetary Defense Coordination Office. The spacecraft was put into hibernation mode in 2011 after twice scanned the entire sky, thereby completing its main objectives. In September 2013, WISE was reactivated, renamed NEOWISE and assigned a new mission to assist NASA’s efforts to identify potentially hazardous near-Earth objects.

    For more information on WISE, visit:

    https://www.nasa.gov/wise

    See the full article here .

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    NASA JPL Campus

    Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, United States. Although the facility has a Pasadena postal address, it is actually headquartered in the city of La Cañada Flintridge [1], on the northwest border of Pasadena. JPL is managed by the nearby California Institute of Technology (Caltech) for the National Aeronautics and Space Administration. The Laboratory’s primary function is the construction and operation of robotic planetary spacecraft, though it also conducts Earth-orbit and astronomy missions. It is also responsible for operating NASA’s Deep Space Network.

    Caltech Logo

    NASA image

     
  • richardmitnick 1:32 pm on July 25, 2017 Permalink | Reply
    Tags: , , , Hidden-sector particles, MiniBooNE, , ,   

    From FNAL: “The MiniBooNE search for dark matter” 

    FNAL II photo

    FNAL Art Image
    FNAL Art Image by Angela Gonzales

    Fermilab is an enduring source of strength for the US contribution to scientific research world wide.

    July 18, 2017
    Ranjan Dharmapalan
    Tyler Thornton

    FNAL/MiniBooNE

    1
    This schematic shows the experimental setup for the dark matter search. Protons (blue arrow on the left) generated by the Fermilab accelerator chain strike a thick steel block. This interaction produces secondary particles, some of which are absorbed by the block. Others, including photons and perhaps dark-sector photons, symbolized by V, are unaffected. These dark photons decay into dark matter, shown as χ, and travel to the MiniBooNE detector, depicted as the sphere on the right.

    Particle physicists are in a quandary. On one hand, the Standard Model accurately describes most of the known particles and forces of interaction between them.

    The Standard Model of elementary particles (more schematic depiction), with the three generations of matter, gauge bosons in the fourth column, and the Higgs boson in the fifth.

    On the other, we know that the Standard Model accounts for less than 5 percent of the universe. About 26 percent of the universe is composed of mysterious dark matter, and the remaining 68 percent of even more mysterious dark energy.

    Some theorists speculate that dark matter particles could belong to a “hidden sector” and that there may be portals to this hidden sector from the Standard Model. The portals allow hidden-sector particles to trickle into Standard Model interactions. A large sensitive particle detector, placed in an intense particle beam and equipped with a mechanism to suppress the Standard Model interactions, could unveil these new particles.

    Fermilab is home to a number of proton beams and large, extremely sensitive detectors, initially built to detect neutrinos. These devices, such as the MiniBooNE detector, are ideal places to search for hidden-sector particles.

    In 2012, the MiniBooNE-DM collaboration teamed up with theorists who proposed new ways to search for dark matter particles. One of these proposals [FNAL PAC Oct 15 2012] involved the reconfiguration of the existing neutrino experiment. This was a pioneering effort that involved close coordination between the experimentalists, accelerator scientists, beam alignment experts and numerous technicians.

    2
    Results of this MiniBooNE-DM search for dark matter scattering off of nucleons. The plot shows the confidence limits and sensitivities with 1, 2σ errors resulting from this analysis compared to other experimental results, as a function of Y (a parameter describing the dark photon mass, dark matter mass and the couplings to the Standard Model) and Mχ (the dark matter mass). For details see the Physical Review Letters paper.

    For the neutrino experiment, the 8-GeV proton beam from the Fermilab Booster hit a beryllium target to produce a secondary beam of charged particles that decayed further downstream, in a decay pipe, into neutrinos. MiniBooNE ran in this mode for about a decade to measure neutrino oscillations and interactions.

    In the dark matter search mode, however, the proton beam was steered past the beryllium target. The beam instead struck a thick steel block at the end of the decay pipe. The resulting charged secondary particles (mostly particles called pions) are absorbed in the steel block, reducing the number of subsequent neutrinos, while the neutral secondary particles remained unaffected. The photons resulting from the decay of neutral pions may have transformed into hidden-sector photons that in turn might have decayed into dark matter, which would travel to the MiniBooNE detector 450 meters away. The experiment ran in this mode for nine months for a dedicated dark matter search.

    Using the previous 10 years’ worth of data as a baseline, MiniBooNE-DM looked for scattered protons and neutrons in the detector. If they found more scattered protons or neutrons than predicted, the excess could indicate a new particle, maybe dark matter, being produced in the steel block. Scientists analyzed multiple types of neutrino interactions at the same time, reducing the error on the signal data set by more than half.

    Analysts concluded that the data was consistent with the Standard Model prediction, enabling the experimenters to set a limit on a specific model of dark matter, called vector portal dark matter. To set the limit, scientists developed a detailed simulation that estimated the predicted proton or neutron response in the detector from scattered dark matter particles. The new limit extends from the low-mass edge of direct-detection experiments down to masses about 1,000 times smaller. Additionally, the result rules out this particular model as a description of the anomalous behavior of the muon seen in the Muon g-2 experiment at Brookhaven, which was one of the goals of the MiniBooNE-DM proposal. Incidentally, researchers at Fermilab will make a more precise measurement of the muon — and verify the Brookhaven result — in an experiment that started up this year.

    This result from MiniBooNE, a dedicated proton beam dump search for dark matter, was published in Physical Review Letters and was highlighted as an “Editor’s suggestion.”

    What’s next? The experiment will continue to analyze the collected data set. It is possible that the dark matter or hidden-sector particles may prefer to scatter off of the lepton family of particles, which includes electrons, rather than off of quarks, which are the constituent of protons and neutrons. Different interaction channels probe different possibilities.

    If the portals to the hidden sector are narrow — that is, if they are weakly coupled — researchers will need to collect more data or implement new ideas to suppress the Standard Model interactions.

    The first results from MiniBooNE-DM show that Fermilab could be at the forefront of searching for hidden-sector particles. Upcoming experiments in Fermilab’s Short-Baseline Neutrino program will use higher-resolution detectors — specifically, liquid-argon time projection chamber technology — expanding the search regions and possibly leading to discovery.

    Ranjan Dharmapalan is a postdoc at Argonne National Laboratory. Tyler Thornton is a graduate student at Indiana University Bloomington.

    See the full article here .

    Please help promote STEM in your local schools.

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    Fermilab Campus

    Fermi National Accelerator Laboratory (Fermilab), located just outside Batavia, Illinois, near Chicago, is a US Department of Energy national laboratory specializing in high-energy particle physics. Fermilab is America’s premier laboratory for particle physics and accelerator research, funded by the U.S. Department of Energy. Thousands of scientists from universities and laboratories around the world
    collaborate at Fermilab on experiments at the frontiers of discovery.

     
  • richardmitnick 12:57 pm on July 25, 2017 Permalink | Reply
    Tags: , , , , , ,   

    From JPL: “A Final Farewell to LISA Pathfinder” 

    NASA JPL Banner

    JPL-Caltech

    July 24, 2017
    Andrew Good
    Jet Propulsion Laboratory, Pasadena, Calif.
    818-393-2433
    andrew.c.good@jpl.nasa.gov

    1
    An artist’s concept of the European Space Agency’s LISA Pathfinder spacecraft, designed to pave the way for a mission detecting gravitational waves. NASA/JPL developed a thruster system on board.

    Official ESA/LISA Pathfinder image

    With the push of a button, final commands for the European Space Agency’s LISA Pathfinder mission were beamed to space on July 18, a final goodbye before the spacecraft was powered down.

    LISA Pathfinder had been directed into a parking orbit in April, keeping it out of Earth’s way. The final action this week switches it off completely after a successful 16 months of science measurements.

    While some spacecraft are flashy, never sitting still as they zip across the solar system, LISA Pathfinder was as steady as they come — literally.

    It housed a space-age motion detector so sensitive that it had to be protected against the force of photons from the Sun. That was made possible thanks to a system of thrusters that applied tiny reactive forces to the spacecraft, cancelling out the force of the Sun and allowing the spacecraft to stay within 10 nanometers of an ideal gravitational orbit.

    These requirements for Pathfinder were so challenging and unique that LISA Pathfinder flew two independent systems based on different designs – one provided by NASA and one by ESA – and ran tests with both during its 16-month mission.

    “We were trying to hold it as stable as the width of a DNA helix,” said John Ziemer, systems lead for the U.S. thruster system at NASA’s Jet Propulsion Laboratory in Pasadena, California. “And we went down from there to the width of part of a DNA helix.”

    JPL managed development of the thruster system, formally called the Space Technology 7 Disturbance Reduction System (ST7-DRS). The thrusters were developed by Busek Co., Inc., Natick, Massachusetts, with technical support from JPL. During the U.S. operations phase, Pathfinder was controlled using algorithims developed by ST7 team members at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. This control system took inputs from the European sensors and sent commands to the thrusters to precisely guide the spacecraft along its path.

    JPL finished primary mission experiments in the fall of 2016. In March and April of this year, they continued validating the algorithms used in stabilizing the spacecraft. They improved them through a number of tests.

    “The main goal for us was to show we can fly the spacecraft drag-free,” Ziemer said. “The main force on the spacecraft comes from the Sun, from photons with extremely tiny force that can subtly move the spacecraft.”

    So why build something this sensitive to begin with?

    LISA Pathfinder was just a starting point. The mission was led by ESA as a stepping-stone of sorts, proving the technology needed for an even more ambitious plan, the Laser Interferometer Space Antenna (LISA): a trio of spacecraft proposed to launch in 2034. With each spacecraft holding as still as possible, they would be able to detect the ripples sent out across space by the merging of black holes.

    ESA/eLISA the future of gravitational wave research

    These ripples, known as gravitational waves, have been a source of intense scientific interest in recent years. The ground-based Laser Interferometry Gravitational Wave Observatory detected gravitational waves for the first time in 2015.

    But there’s a bigger role for thrusters like the ones on LISA Pathfinder. Ziemer said the operation of super-steady thrusters could serve as an alternative to reaction wheels, the current standard for rotating and pointing spacecraft.

    “This kind of technology could be essential for space telescopes,” Ziemer said. “They could potentially hold them still enough to image exoplanets, or allow for formation flying of a series of spacecraft.”

    The thrusters are an enabling technology, opening up a magnitude of precision that simply wasn’t available before.

    The Pathfinder spacecraft was built by Airbus Defence and Space, Ltd., United Kingdom. Airbus Defence and Space, GmbH, Germany, is the payload architect for the LISA Technology Package.

    For more information about ST7-DRS, visit:

    http://www.jpl.nasa.gov/news/news.php?feature=4825

    [It was my understanding that this satellite would have a further mission in detecting NEO’s.]

    See the full article here .

    Please help promote STEM in your local schools.

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    NASA JPL Campus

    Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, United States. Although the facility has a Pasadena postal address, it is actually headquartered in the city of La Cañada Flintridge [1], on the northwest border of Pasadena. JPL is managed by the nearby California Institute of Technology (Caltech) for the National Aeronautics and Space Administration. The Laboratory’s primary function is the construction and operation of robotic planetary spacecraft, though it also conducts Earth-orbit and astronomy missions. It is also responsible for operating NASA’s Deep Space Network.

    Caltech Logo

    NASA image

     
  • richardmitnick 7:40 am on July 25, 2017 Permalink | Reply
    Tags: Astron, , , , , Lofar Ireland,   

    From Astron: “LOFAR Ireland officially launched” 

    ASTRON bloc

    Netherlands Institute for Radio Astronomy

    ASTRON LOFAR Map

    ASTRON LOFAR Radio Antenna Bank

    New antenna station further increases sensitivity of the world’s largest radio telescope

    On 27 July 2017, the newly built Low Frequency Array (LOFAR) station in Ireland will be officially opened.

    1
    Astron Lofar Ireland Section

    This extends the largest radio telescope in the world, connecting to its central core of antennas in the north of the Netherlands, now forming a network of two thousand kilometres across. Astronomers can now study the history of the universe in even more detail. The station will be opened by the Irish Minister for Training, Skills, Innovation, Research and Development, John Halligan.

    The international LOFAR telescope (ILT) is a European network of radio antennas, connected by a high-speed fibre optic network. With the data of thousands of antennas together, now including the Irish antennas, powerful computers create a virtual dish with a diameter of two thousand kilometres. The telescope thus gets has an even sharper and more sensitive vision.

    More detail

    Rene Vermeulen, Director of the ILT, is very excited about this new collaboration. “Thanks to the new LOFAR station in Ireland, we can observe the universe in even more detail. For example, we can look more closely at objects near and far, from our Sun to black holes, magnetic fields, and the emergence of galaxies in the early Universe. These are important areas of research for astronomers in the Netherlands and other ILT partner countries.”

    The Irish LOFAR team is led by Professor Peter Gallagher (Trinity College Dublin), an expert on Solar astrophysics. Vermeulen: “Studying the Sun, including solar flares, is an important branch of astronomical research. In this and other areas Irish researchers bring important reinforcement to our partnership.”

    Successful tests

    LOFAR was designed and built by ASTRON, the Netherlands Institute for Radio Astronomy. Earlier this month, a team from ASTRON conducted the final delivery tests of the Irish station on the Birr castle estate. The antennas, which conduct measurements at the lowest frequencies that can be observed from the earth, perform according to specification. The fibre optic network has already been successfully connected to the supercomputer in the computing centre in Groningen, which combines the data of the thousands of antennas.

    See the full article here .

    Please help promote STEM in your local schools.

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    ASTRON-Westerbork Synthesis Radio Telescope
    Westerbork Synthesis Radio Telescope (WSRT)

    ASTRON was founded in 1949, as the Foundation for Radio radiation from the Sun and Milky Way (SRZM). Its original charge was to develop and operate radio telescopes, the first being systems using surplus wartime radar dishes. The organisation has grown from twenty employees in the early 1960’s to about 180 staff members today.

     
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