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  • richardmitnick 4:07 pm on October 25, 2014 Permalink | Reply
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    From Quanta: “Dwarf Galaxies Dim Hopes of Dark Matter” 

    Quanta Magazine
    Quanta Magazine

    October 25, 2014
    Natalie Wolchover

    Once again, a shadow of a signal that scientists hoped would amplify into conclusive evidence of dark matter has instead flatlined, repeating a maddening refrain in the search for the invisible, omnipresent particles.

    The Fermi Large Area Telescope (LAT) failed to detect the glow of gamma rays emitted by annihilating dark matter in miniature “dwarf” galaxies that orbit the Milky Way, scientists reported Friday at a meeting in Nagoya, Japan. The hint of such a glow showed up in a Fermi analysis last year, but the statistical bump disappeared as more data accumulated.

    NASA Fermi Telescope
    NASA/Fermi Gamma Ray Spacecraft

    LAT cutaway

    “We were obviously somewhat disappointed not to see a signal,” said Matthew Wood, a postdoctoral researcher at Stanford University who was centrally involved the Fermi-LAT collaboration’s new analysis, in an email.

    Scientists homed in on the dwarf galaxies after Dan Hooper, a theoretical astrophysicist at the Fermi National Accelerator Laboratory in Batavia, Ill., and Lisa Goodenough, his graduate student at the time, detected an unexplained gamma-ray signal coming from the center of the Milky Way in 2009. Hooper and several collaborators proposed that the gamma rays might be due to dark matter in the form of WIMPs, or weakly interacting massive particles, which are the leading candidates for the invisible substance that comprises six-sevenths of the universe’s mass. When two WIMPs collide in the dense galactic center, they should annihilate, with gamma rays as the fallout. Over the past five years the intriguing gamma-ray signal has seemed more and more likely to be the detritus of annihilating WIMPs.

    However, scientists knew that the same glow could also originate from an unknown population of millisecond pulsars in the galactic center — bright, rapidly spinning stars that spew gamma rays into space.

    Looking for ways to distinguish the two possibilities, scientists turned to dwarf galaxies, which are thought to be rich in dark matter but free of pulsars. If researchers found gamma rays pouring out of dwarf galaxies, the observation would rule out alternative explanations and provide emphatic evidence of WIMPs.

    Yet no such signal has been detected in five years’ worth of the highest-quality data from 15 nearby dwarfs, Wood and his colleagues report. “The case for the dark-matter interpretation of the galactic-center excess is substantially weakened,” he said.

    Olena Shmahalo/Quanta Magazine; data courtesy of Matthew Wood

    Under the most generous assumptions about the density of dark matter, new observations of dwarf galaxies exclude some, but not all, models of dark-matter particles that could be producing a signal coming from the center of the Milky Way. The range of particle properties proposed in a 2014 paper by Dan Hooper and colleagues (purple) is still viable, while a model proposed by Francesca Calore et al. (orange), which experts consider the most comprehensive, predicts a range of properties that is cut exactly in half. Under less generous assumptions, all except the Calore model are excluded.

    The possibility remains that the signal from the Milky Way’s center does come from dark matter, but only if the density of dark matter in the galaxy is at the high end of researchers’ estimates. If dark matter is sufficiently dense, it doesn’t have to annihilate at a very high rate to explain the signal from the galactic center. And if dark matter annihilates at a low rate, then researchers shouldn’t be surprised when they don’t see a signal coming from the more-diffuse dwarfs.

    “At this stage we do not entirely exclude all of the dark-matter models proposed to explain the reported excess,” Wood said.

    Hooper, whose model barely survives the blow of the new dwarf-galaxy findings, seems unfazed, and he maintains his position that the signal from the galactic center most likely comes from colliding WIMPs that vanish in puffs of gamma rays. “That’s where my money is,” he told Quanta Magazine in March. Speaking from the meeting in Japan, he said, “That hasn’t changed in any significant way.”

    Other scientists agree that the dark-matter explanation of the gamma-ray excess is still viable, for now. “It is what it is,” said Savvas Koushiappas, a physicist at Brown University and co-author of another recent analysis of gamma rays from the dwarfs. “There is a dark-matter interpretation, and the dwarfs at the moment did not rule it out, or confirm it. However, we are close.”

    Tracy Slatyer, a physicist at the Massachusetts Institute of Technology who has collaborated with Hooper on models of the galactic-center excess, said she finds the new results “really encouraging.”

    “Of course, I would like the galactic-center excess to come from annihilating dark matter, but I would much rather know one way or the other,” she said. “This result increases the probability that we will know for sure in the near future.”

    The paradigm that dark matter is likely composed of WIMPs has long reigned among physicists because of the “WIMP miracle,” or the fact that the same hypothetical particle could account for mysteries of both the cosmic and the quantum worlds. With roughly the same mass as many of the known particles in nature, WIMPs would counteract the effects of those particles in quantum equations in a way that would make apparently faulty calculations work. And the presence of a halo of WIMPs around galaxies would explain why the galaxies rotate faster than expected at their outskirts — the most compelling indirect evidence that dark matter exists.

    But the fact that WIMPs would represent an elegant solution to deep questions doesn’t mean they’re real. Scientists have spent the past decade monitoring ultra-cooled vats of liquid chemicals located deep underground in repurposed mine shafts all over the world, hoping that WIMPs would occasionally leave traces of energy as they traversed the liquids. But the search has not produced a single convincing signal.

    As the experiments become ever more sensitive, they eat away at the abstract space of all viable WIMP models, giving it the look of Swiss cheese. The discouraging results have pushed researchers to get more creative. “Even though many people are working very hard on the WIMP paradigm, people are starting to think more broadly,” said Mark Trodden, a professor of theoretical physics at the University of Pennsylvania.

    Dwarf galaxies have already inspired alternatives to the standard WIMP picture. If dark-matter particles can interact with one another (instead of “weakly interacting” only with ordinary matter, as in conventional WIMP models), they will transfer heat as they collide. “When you transfer heat, you get a less dense center,” explained David Spergel, an astrophysicist at Princeton University who, along with his colleague Paul Steinhardt, first proposed the self-interacting dark-matter scenario in 2000. Indeed, astronomers have observed that the cores of dwarf galaxies are less dense than would be expected based on simulations of galaxy formation that use WIMPs.

    J. Bullock, M. Geha, R. Powell
    A map of dwarf galaxies orbiting the Milky Way Galaxy. Each dwarf contains up to several billion stars, compared to several hundred billion in the Milky Way.

    Self-interacting dark matter has attracted growing interest among scientists, but not everyone feels comfortable postulating a new property to patch over the problems with current models.

    “We’re just making this invisible particle increasingly complicated,” said Justin Khoury, a theoretical physicist at the University of Pennsylvania. “I’m torn about that.”

    Meanwhile, new and improved simulations by Alyson Brooks of Rutgers University and colleagues suggest that dwarf galaxies can be modeled correctly without dark matter self-interactions after all, if the simulations include the effects of ordinary particles — the one-seventh of all matter that we actually see, but which models often ignore for the sake of simplicity. When stars go supernova, Brooks explained, they produce hot bubbles of gas that rapidly expand. “It turns out that process gives energy to the dark matter in the center of galaxies and pushes it out,” she said.

    Although Brooks’ simulations match observations, some other leading modelers can’t get the effects of ordinary matter to fix the discrepancy in their own simulations, fueling the interest in self-interacting dark matter.

    Complicating the debate is the fact that if dark-matter particles self-interact, that means they don’t annihilate upon contact in bursts of gamma rays. In that case, the signal from the Milky Way’s center would not come from dark matter.

    “If this all sounds lively and contradictory and confused, you have the right idea,” Steinhardt said.

    Khoury has moved the furthest from the WIMP picture with a recent paper postulating that dark matter may not be composed of particles at all. His theory revamps an old idea called modified Newtonian dynamics, or MOND, which proposes a change to the law of gravity. In Khoury’s theory, dark matter is a fluidlike field that permeates space, interacting with the gravitational fields of galaxies in a way that alters their rotation.

    Erik Verlinde, a theoretical physicist at the University of Amsterdam in the Netherlands, has proposed a different modified-gravity theory, one in which dark matter doesn’t exist at all and the rotational speeds of galaxies reflect the entropy, or disorder, of space and time.

    At this stage, one theorist’s guess seems as good as another’s.

    “There are many, many, many things that dark matter could be,” Trodden said. “If you gave me license to write down particle physics [models] that could give me dark matter, I could write down 10 that haven’t been thought about before.” As for which ones hold the most promise, the universe isn’t telling.

    See the full article here.

    Formerly known as Simons Science News, Quanta Magazine is an editorially independent online publication launched by the Simons Foundation to enhance public understanding of science. Why Quanta? Albert Einstein called photons “quanta of light.” Our goal is to “illuminate science.” At Quanta Magazine, scientific accuracy is every bit as important as telling a good story. All of our articles are meticulously researched, reported, edited, copy-edited and fact-checked.

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  • richardmitnick 3:24 pm on October 25, 2014 Permalink | Reply
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    From livesience: “Telltale Signs of Life Could Be Deepest Yet” 


    October 24, 2014
    Becky Oskin

    Telltale signs of life have been discovered in rocks that were once 12 miles (20 kilometers) below Earth’s surface — some of the deepest chemical evidence for life ever found.

    White aragonite veins on Washington’s San Juan Islands may contain evidence of deep microbial life.
    Credit: Philippa Stoddard

    Researchers found carbon isotopes in rocks on Washington state’s South Lopez Island that suggest the minerals grew from fluids flush with microbial methane. Methane from living creatures has distinct levels of carbon isotopes that distinguish it from methane gas that arises from rocks. (Isotopes are atoms of the same element with different numbers of neutrons in their nuclei.)

    In a calcium carbonate mineral called aragonite, the standard mix of carbon isotopes was radically shifted toward lighter carbon isotopes (by about 50 per mil, or parts per thousand). This ratio is characteristic of methane gas made by microorganisms, said Philippa Stoddard, an undergraduate student at Yale University who presented the research Tuesday (Oct. 21) at the Geological Society of America‘s annual meeting in Vancouver, British Columbia. “These really light signals are only observed when you have biological processes,” she told Live Science.

    The pale aragonite veins cut through basalt rocks that sat offshore North America millions of years ago. The veins formed after the basalt was sucked into an ancient subduction zone, one that predated today’s Cascadia subduction zone. Two tectonic plates smash together at subduction zones, and one plate descends under the other, creating deep trenches.

    Methane gas supplied the carbon as aragonite crystallized in cracks in the basalt, and replaced pre-existing limestone. The researchers think that microbes produced the methane gas as a waste product.

    “We reason that you could have life deeper in subduction zones, because you have a lot of water embedded in those rocks, and the rocks stay cold longer as the [plate] comes down,” Stoddard said.

    But the South Lopez Island aragonite suggests the minerals formed under extreme conditions that push the limits of life on Earth. For example, temperatures reached more than 250 degrees Fahrenheit (122 degrees Celsius), above the stability limit for DNA, Stoddard said. However, the researchers think the higher pressures at these depths may have counterbalanced the effects of the heat. The rocks are now visible thanks to faulting, which pushed them back up to the surface.

    Stoddard and her collaborators plan to sample more of the aragonite and other rocks nearby, to gain a better understanding of where the fluids came from and pin down the temperatures at which the rocks formed.

    Methane seeps teeming with million of microbes are found on the seafloor offshore Washington and Oregon along the Cascadia subduction zone. And multicellular life has been documented in the Mariana Trench, the deepest spot on Earth, and in South African mines 0.8 miles (1.3 km) deep. Researchers also have discovered microbes feasting on rocks within the oceanic crust itself.

    See the full article here.

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  • richardmitnick 7:37 am on October 25, 2014 Permalink | Reply
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    From Frontier Fields: “First Galaxy Field Complete: Abell 2744″ 

    Frontier Fields
    Frontier Fields

    October 23, 2014
    Tony Darnell

    This past summer, the Hubble Frontier Fields team completed observations of the first cluster on its list: Abell 2744! The second set of observations — astronomers call them epochs — consisted of 70 orbits and marks the completion of the first Frontier Fields galaxy cluster. During this set, Hubble’s Advanced Camera for Surveys (ACS) was pointed at the main galaxy cluster and studied the visible-light portions of the spectrum, while the Wide Field Camera 3 (WFC3) looked at the parallel field in the infrared.

    NASA Hubble ACS

    NASA Hubble WFC3

    Remember that Hubble will visit each field multiple times, with Hubble oriented such that one set of observations will point WFC3 at the cluster and ACS at a parallel field adjacent to the cluster (that’s one epoch). The telescope will then come back and do another set of observations with the cameras switched: ACS pointing at the cluster and WFC3 pointing to the parallel field (that’s the second one).

    The Frontier Fields team does this to allow for complete wavelength coverage in both infrared and visible light for the galaxy cluster and the parallel field.

    The first epoch, completed in November 2013, consisted of 87 orbits. This brings the total amount of time Hubble looked at this cluster to 157 orbits.

    Final mosaic of the Frontier Fields galaxy cluster Abell 2744. This image is the culmination of both epochs totaling 157 Hubble orbits. The numbers prefixed with “F” are the Hubble filters used by the ACS and WFC3 cameras to take the image. The scale bar of 30″ is approximately 2% the angular size of the full moon as seen from Earth – very small! Credit: NASA, ESA, and J. Lotz, M. Mountain, A. Koekemoer, and the HFF Team (STScI)

    Final mosaic of the Frontier Fields galaxy cluster Abell 2744. This image is the culmination of both epochs totaling 157 Hubble orbits. The numbers prefixed with “F” are the Hubble filters used by the ACS and WFC3 cameras to take the image. The scale bar of 30″ is approximately 2% the angular size of the full moon as seen from Earth – very small!
    Credit: NASA, ESA, and J. Lotz, M. Mountain, A. Koekemoer, and the HFF Team (STScI)

    Parallel field of Frontier Field Abell 2744

    This is the completed composite mosaic of the Parallel Fields observed with galaxy cluster Abell 2744.
    Credit: NASA, ESA, and J. Lotz, M. Mountain, A. Koekemoer, and the HFF Team (STScI)

    See? Epic! Er, I mean epoch.

    Once the second epoch was completed, some of the faintest galaxies ever seen were measured for the first time. Astronomers have been working on these images since their release, and we are anxiously awaiting to hear what they find.

    See the full article here.

    Frontier Fields draws on the power of massive clusters of galaxies to unleash the full potential of the Hubble Space Telescope. The gravity of these clusters warps and magnifies the faint light of the distant galaxies behind them. Hubble captures the boosted light, revealing the farthest galaxies humanity has ever encountered, and giving us a glimpse of the cosmos to be unveiled by the James Webb Space Telescope.

    NASA Hubble Telescope
    NASA James Webb Telescope
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  • richardmitnick 6:36 pm on October 24, 2014 Permalink | Reply
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    From Nautilus: “Who Really Found the Higgs Boson” 



    October 23, 2014
    By Neal Hartman
    Illustration by Owen Freeman
    Also stock photos

    To those who say that there is no room for genius in modern science because everything has been discovered, Fabiola Gianotti has a sharp reply. “No, not at all,” says the former spokesperson of the ATLAS Experiment, the largest particle detector at the Large Hadron Collider at CERN. “Until the fourth of July, 2012 we had no proof that nature allows for elementary scalar fields. So there is a lot of space for genius.”


    CERN LHC Map
    CERN LHC Grand Tunnel
    CERN LHC particles
    LHC at CERN

    She is referring to the discovery of the Higgs boson two years ago—potentially one of the most important advances in physics in the past half century. It is a manifestation of the eponymous field that permeates all of space, and completes the standard model of physics: a sort of baseline description for the existence and behavior of essentially everything there is.

    By any standards, it is an epochal, genius achievement.

    What is less clear is who, exactly, the genius is. An obvious candidate is Peter Higgs, who postulated the Higgs boson, as a consequence of the Brout-Englert-Higgs mechanism, in 1964. He was awarded the Nobel Prize in 2013 along with Francois Englert (Englert and his deceased colleague Robert Brout arrived at the same result independently). But does this mean that Higgs was a genius? Peter Jenni, one of the founders and the first “spokesperson” of the ATLAS Experiment Collaboration (one of the two experiments at CERN that discovered the Higgs particle), hesitates when I ask him the question.

    “They [Higgs, Brout and Englert] didn’t think they [were working] on something as grandiose as [Einstein’s relativity],” he states cautiously. The spontaneous symmetry breaking leading to the Higgs “was a challenging question, but [Albert Einstein] saw something new and solved a whole field. Peter Higgs would tell you, he worked a few weeks on this.”

    The ability of the precocious individual physicist to suggest a new data cut or filter is restricted.

    What, then, of the leaders of the experimental effort, those who directed billions of dollars in investment and thousands of physicists, engineers, and students from almost 40 countries for over three decades? Surely there must have been a genius mastermind directing this legion of workers, someone we can single out for his or her extraordinary contribution.

    “No,” says Gianotti unequivocally, which is rare for a physicist, “it’s completely different. The instruments we have built are so complex that inventiveness and creativity manifests itself in the day-by-day work. There are an enormous amount of problems that require genius and creativity to be spread over time and over many people, and all at the same level.”

    Scientific breakthroughs often seem to be driven by individual genius, but this perception belies the increasingly collaborative nature of modern science. Perhaps nothing captures this dichotomy better than the story of the Higgs discovery, which presents a stark contrast between the fame awarded to a few on the one hand, and the institutionalized anonymity of the experiments that made the discovery possible on the other.

    An aversion to the notion of exceptional individuals is deeply rooted within the ATLAS collaboration, a part of its DNA. Almost all decisions in the collaboration are approved by representative groups, such as the Institute Board, the Collaboration Board, and a plethora of committees and task forces. Consensus is the name of the game. Even the effective CEO, a role Gianotti occupied from 2009 to 2013, is named the “Spokesperson.” She spoke for the collaboration, but did not command it.

    Collectivity is crucial to ATLAS in part because it’s important to avoid paying attention to star personalities, so that the masses of physicists in the collaboration each feel they own the research in some way. Almost 3,000 people qualify as authors on the key physics papers ATLAS produces, and the author list can take almost as many pages as the paper itself.

    The genius of crowds: Particle physics collaborations can produce academic papers with hundreds of authors. One 2010 paper was 40 pages long—with 10 pages devoted to the authors list, pictured here.

    On a more functional level, this collectivity also makes it easier to guard against bias in interpreting the data. “Almost everything we do is meant to reduce potential bias in the analysis,” asserts Kerstin Tackmann, a member of the Higgs to Gamma Gamma analysis group during the time of the Higgs discovery, and recent recipient of the Young Scientist Prize in Particle Physics. Like many physicists, Tackmann verges on the shy, and speaks with many qualifications. But she becomes more forceful when conveying the importance of eliminating bias.

    “We don’t work with real data until the very last step,” she explains. After the analysis tools—algorithms and software, essentially—are defined, they are applied to real data, a process known as the unblinding. “Once we look at the real data,” says Tackmann, “we’re not allowed to change the analysis anymore.” To do so might inadvertently create bias, by tempting the physicists to tune their analysis tools toward what they hope to see, in the worst cases actually creating results that don’t exist. The ability of the precocious individual physicist to suggest a new data cut or filter is restricted by this procedure: He or she wouldn’t even see real data until late in the game, and every analysis is vetted independently by multiple other scientists.

    Most people in the collaboration work directly “for” someone who is in no way related to their home institute, which actually writes their paycheck.

    This collective discipline is one way that ATLAS tames the complexity of the data it produces, which in raw form is voluminous enough to fill a stack of DVDs that reaches from the earth to the moon and back again, 10 times every year. The data must be reconstructed into something that approximates an image of individual collisions in time and space, much like the processing required for raw output from a digital camera.

    But the identification of particles from collisions has become astoundingly more complex since the days of “scanning girls” and bubble chamber negatives, where actual humans sat over enlarged images of collisions and identified the lines and spirals as different particles. Experimentalists today need to have expert knowledge of the internal functioning of the different detector subsystems: pixel detector, silicon strip tracker, transition radiation tracker, muon system, and calorimeters, both hadronic and electromagnetic. Adjustments made to each subsystem’s electronics, such as gain or threshold settings, might cause the absence or inclusion of what looks like real data but isn’t. Understanding what might cause false or absent signals, and how they can be accounted for, is the most challenging and creative part of the process. “Some people are really clever and very good at this,” says Tackmann.

    The process isn’t static, either. As time goes on, the detector changes from age and radiation damage. In the end the process of perfecting the detector’s software is never-ending, and the human requirements are enormous: roughly 100 physicists were involved in the analysis of a single and relatively straightforward particle signature, the decay of the Higgs into two Gamma particles. The overall Higgs analysis was performed by a team of more than 600 physicists.

    The depth and breadth of this effort transform the act of discovery into something anonymous and distributed—and this anonymity has been institutionalized in ATLAS culture. Marumi Kado, a young physicist with tousled hair and a quiet zen-like speech that borders on a whisper, was one of the conveners of the “combined analysis” group that was responsible for finally reaching the level of statistical significance required to confirm the Higgs discovery. But, typically for ATLAS, he downplays the importance of the statistical analysis—the last step—in light of the complexity of what came before. “The final analysis was actually quite simple,” he says. “Most of the [success] lay in how you built the detector, how well you calibrated it, and how well it was designed from the very beginning. All of this took 25 years.”

    The deeply collaborative work model within ATLAS meant that it wasn’t enough for it to innovate in physics and engineering—it also needed to innovate its management style and corporate culture. Donald Marchand, a professor of strategy execution and information management at IMD Business School in Lausanne, describes ATLAS as following a collaborative mode of working that flies in the face of standard “waterfall”—or top down—management theory.

    Marchand conducted a case study on ATLAS during the mid-2000s, finding that the ATLAS management led with little or no formal authority. Most people in the collaboration work directly “for” someone who is in no way related to their home institute, which actually writes their paycheck. For example, during the construction phase, the project leader of the ATLAS pixel detector, one of its most data-intensive components, worked for a U.S. laboratory in California. His direct subordinate, the project engineer, worked for an institute in Italy. Even though he was managing a critical role in the production process, the project leader had no power to promote, discipline, or even formally review the project engineer’s performance. His only recourse was discussion, negotiation, and compromise. ATLAS members are more likely to feel that they work with someone, rather than for them.

    Similarly, funding came from institutes in different countries through “memorandums of understanding” rather than formal contracts. The collaboration’s spokesperson and other top managers were required to follow a politic of stewardship, looking after the collaboration rather than directing it. If collaboration members were alienated, that could mean the loss of the financial and human capital they were investing. Managers at all levels needed to find non-traditional ways to provide feedback, incentives, and discipline to their subordinates.

    One famous member of the collaboration is looked upon dubiously by many, who see him as drawing too much attention to himself.

    The coffee chat was one way to do this, and became the predominant way to conduct the little daily negotiations that kept the collaboration running. Today there are cafés stationed all around CERN, and they are full from morning to evening with people having informal meetings. Many physicists can be seen camped out in the cafeteria for hours at a time, working on their laptops between appointments. ATLAS management also created “a safe harbor, a culture within the organization that allows [employees] to express themselves and resolve conflicts and arguments without acrimony,” Marchand says.

    The result is a management structure that is remarkably effective and flexible. ATLAS managers consistently scored in the top 5 percent of a benchmark scale that measures how they control, disseminate, and capitalize on the information capital in their organization. Marchand also found that the ATLAS management structure was effective at adapting to changing circumstances, temporarily switching to a more top-down paradigm during the core production phase of the experiment, when thousands of identical objects needed to be produced on assembly lines all over the world.

    This collaborative culture didn’t arise by chance; it was built into ATLAS from the beginning, according to Marchand. The original founders infused a collaborative ethic into every person that joined by eschewing personal credit, talking through conflicts face to face, and discussing almost everything in open meetings. But that ethic is codified nowhere; there is no written code of conduct. And yet it is embraced, almost religiously, by everyone that I spoke with.

    Collaboration members are sceptical of attributing individual credit to anything. Every paper includes the entire author list, and all of ATLAS’s outreach material is signed “The ATLAS Collaboration.” People are suspicious of those that are perceived to take too much personal credit in the media. One famous member of the collaboration (as well as a former rock star and host of the highly successful BBC series, Horizon) is looked upon dubiously by many, who see him as drawing too much attention to himself through his association with the experiment.

    MIND THE GAP: Over 60 institutes collaborated to build and install a new detector layer inside a 9-millimeter gap between the beam pipe (the evacuated pipe inside of which protons circulate) and the original detector.ATLAS Experiment © 2014 CERN

    In searching for genius at ATLAS, and other experiments at CERN, it seems almost impossible to point at anything other than the collaborations themselves. More than any individual, including the theorists who suggest new physics and the founders of experimental programs, it is the collaborations that reflect the hallmarks of genius: imagination, persistence, open-mindedness, and accomplishment.

    The results speak for themselves: ATLAS has already reached its first key objective in just one-tenth of its projected lifetime, and continues to evolve in a highly collaborative way. This May, one of the first upgrades to the detector was installed. Called the Insertable B-Layer (IBL), it grew out of a task force formed near the end of ATLAS’s initial commissioning period, in 2008, with the express goal of documenting why inserting another layer of detector into a 9-millimeter clearance space just next to the beam pipe was considered impossible.

    Consummate opportunists, the task force members instead came up with a design that quickly turned into a new subproject. And though it’s barely larger than a shoebox, the IBL’s construction involved more than 60 institutes all over the world, because everyone wanted to be involved in this exciting new thing. When it came time to slide the Insertable B-layer sub-detector into its home in the heart of ATLAS earlier this year, with only a fraction of a millimeter of clearance over 7 meters in length, the task was accomplished in just two hours—without a hitch.

    Fresh opportunities for new genius abound. Gianotti singles out dark matter as an example, saying “96 percent of the universe is dark. We don’t know what it’s made of and it doesn’t interact with our instruments. We have no clue,” she says. “So there is a lot of space for genius.” But instead of coming from the wild-haired scientist holding a piece of chalk or tinkering in the laboratory, that genius may come from thousands of people working together.

    Neal Hartman is a mechanical engineer with Lawrence Berkeley National Laboratory that has been working with the ATLAS collaboration at CERN for almost 15 years. He spends much of his time on outreach and education in both physics and general science, including running CineGlobe, a science-inspired film festival at CERN.

    See the full article, with notes, here.

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  • richardmitnick 1:35 pm on October 24, 2014 Permalink | Reply
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    From Daily Californian: “Senate meets to support observatory, proposition, research campus” 

    Daily Californian

    The Daily Californian

    October 24, 2014
    Heyun Jeong

    The ASUC Senate passed bills supporting the preservation of Lick Observatory, a state proposition and a new research campus on Wednesday evening.

    UCO Lick Observatory
    Lick Observatory

    Adopted with unanimous consent, the bills establish the ASUC’s support for the different issues and order executives to write up letters or public statements on behalf of the ASUC.

    In response to talks of terminating UC funding for Lick Observatory by 2018, CalSERVE Senator Lavanya Jawaharlal sponsored SB 25 to show support in continuing the observatory’s operations. The bill establishes a committee of students to raise awareness and propose alternative funding options and urges the UC Office of the President to recommit funds.

    The talks of disinvestment make it “difficult to get outside funding, when private donors are wondering why they should invest money when the UC is cutting funding,” Jawaharlal said.

    The committee, which will be made up of two senators and five appointed students, will work on increasing communication with the campus administration and raising student awareness not only on the UC Berkeley campus, but also across the entire UC system.

    “It’s a UC-system owned observatory and not just Berkeley,” she said. “It affects all campuses. … It’s important to raise student awareness and mobilize all of the UC system students.”

    According to Jawaharlal, the ASUC is the first student government to pass such a bill or create a special committee for the observatory.

    The senate also passed a bill in support of Proposition 47, which would reclassify certain crimes to misdemeanors instead of felonies.

    Sponsored by CalSERVE Senator Yordanos Dejen, the bill states that the proposition “will ensure that prison spending is focused on violent and serious offenses and will maximize alternatives for non-serious, nonviolent crime.”

    The senate also showed support for plans of a research campus to be built in Richmond.

    The Richmond Bay Campus, which will be developed in phases over the next 40 years, will provide additional research facilities for both UC Berkeley and the Lawrence Berkeley National Laboratory. By having the second campus in Richmond, bill sponsor and CalSERVE Senator Austin Pritzkat said he envisions that the campus will provide a much-needed revitalization of the economy for the surrounding neighborhood.

    Finance officer Dennis Lee was also confirmed as one of the two undergraduate representatives to the Student Union Board. He will replace Arushi Saxena and serve for the rest of the year with Ismael Contreras.

    Lee said he hopes to increase transparency by connecting the Student Union and the ASUC as the board focuses on overseeing commercial activities concerning the new Student Union, set to open next fall.

    See the full article here.

    The Daily Californian is an independent, student-run newspaper published by the Independent Berkeley Students Publishing Company, Inc. The newspaper serves the UC Berkeley campus and its surrounding community, publishing Monday through Friday during the academic year and twice a week during the summer. Established in 1871, The Daily Californian is one of the oldest newspapers on the West Coast and one of the oldest college newspapers in the country. Daily Cal staffers have the unique opportunity of gaining daily metro news experience in the lively city of Berkeley. The newspaper has consistently covered the city and its institutions since its establishment, allowing student journalists to report on campus as well as city news. The Daily Cal also operates Best of Berkeley, a city guide and local arts Web site for the city of Berkeley.

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  • richardmitnick 12:00 pm on October 24, 2014 Permalink | Reply
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    From NYT: “Charles Munger, Warren Buffett’s Longtime Business Partner, Makes $65 Million Gift” 

    New York Times

    The New York Times

    October 24, 2014
    Michael J. de la Merced

    Charles T. Munger has been known for many things over his decades-long career, including longtime business partner of Warren E. Buffett; successful investor and lawyer; and plain-spoken commentator with a wide following.


    Now Mr. Munger, 90, can add another title to that list: deep-pocketed benefactor to the field of theoretical physics.

    He was expected to announce on Friday that he has donated $65 million to the Kavli Institute for Theoretical Physics at the University of California, Santa Barbara. The gift — the largest in the school’s history — will go toward building a 61-bed residence for visitors to the institute, which brings together physicists for weeks at a time to exchange ideas.

    “U.C.S.B. has by far the most important program for visiting physicists in the world,” Mr. Munger said in a telephone interview. “Leading physicists routinely are coming to the school to talk to one another, create new stuff, cross-fertilize ideas.”

    UC Santa Barbara Campus

    The donation is the latest gift by Mr. Munger, a billionaire who has not been shy in giving away the wealth he has accumulated as vice chairman of Mr. Buffett’s Berkshire Hathaway to charitable causes.

    Though perhaps not as prominent a donor as his business partner, who cocreated the Giving Pledge campaign for the world’s richest people to commit their wealth to philanthropy, Mr. Munger has frequently donated big sums to schools like Stanford and the Harvard-Westlake School. (He has not signed on to the Giving Pledge campaign.)

    The biggest beneficiary of his largess thus far has been the University of Michigan, his alma mater. Last year alone, he gave $110 million worth of Berkshire shares — one of the biggest gifts in the university’s history — to create a new residence intended to help graduate students from different areas of study mingle and share ideas.

    That same idea of intellectual cross-pollination underpins the Kavli Institute, which over 35 years has established itself as a haven for theoretical physicists from around the world to meet and discuss potential new developments in their field.

    Funded primarily by the National Science Foundation, the institute has produced advances in the understanding of white dwarf stars, string theory and quantum computing.

    A former director of the institute, David J. Gross, shared in the 2004 Nobel Prize in Physics for work that shed new light on the fundamental force that binds together the atomic nucleus.

    “Away from day-to-day responsibilities, they are in a different mental state,” Lars Bildsten, the institute’s current director, said of the center’s visitors. “They’re more willing to wander intellectually.”

    To Mr. Munger, such interactions are crucial for the advancement of physics. He cited international conferences attended by the likes of [Albert]Einstein and Marie Curie.

    Mr. Munger himself did not study physics for very long, having taken a class at the California Institute of Technology while in the Army during World War II. But as an avid reader of scientific biography, he came to appreciate the importance of the field.

    And he praised the rise of the University of California, Santa Barbara, as a leading haven for physics, particularly given its status as a relatively young research institution.

    But while the Kavli Institute conducts various programs throughout the year for visiting scientists, it has long lacked a way for physicists to spend time outside of work hours during their stays. A permanent residence hall would allow them to mingle even more, in the hope of fostering additional eureka moments.

    “We want to make their hardest choice, ‘Which barbecue to go to?’ ” Mr. Bildsten joked.

    Though Mr. Munger has some ties to the University of California, Santa Barbara — a grandson is an alumnus — he was first introduced to the Kavli Institute through a friend who lives in Santa Barbara.

    During one of the pair’s numerous fishing trips, that friend, Glen Mitchel, asked the Berkshire vice chairman to help finance construction of a new residence. The university had already reserved a plot of land for the dormitory in case the institute raised the requisite funds.

    “It wasn’t a hard sell,” Mr. Munger said.

    “Physics is vitally important,” he added. “Everyone knows that.”

    See the full article here.

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  • richardmitnick 11:04 am on October 24, 2014 Permalink | Reply
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    From CfA: “Accreting Supermassive Black Holes in the Early Universe” 

    Harvard Smithsonian Center for Astrophysics

    Center For Astrophysics

    October 24, 2014
    No Writer Credit

    Supermassive black holes containing millions or even billions of solar-masses of material are found at the nuclei of galaxies. Our Milky Way, for example, has a nucleus with a black hole with about four million solar masses of material. Around the black hole, according to theories, is a torus of dust and gas, and when material falls toward the black hole (a process called accretion) the inner edge of the disk can be heated to millions of degrees. Such accretion heating can power dramatic phenomena like bipolar jets of rapidly moving charged particles. Such actively accreting supermassive black holes in galaxies are called active galactic nuclei (AGN).


    The evolution of AGN in cosmic time provides a picture of their role in the formation and co-evolution of galaxies. Recently, for example, there has been some evidence that AGN with more modest luminosities and accretion rates (compared to the most dramatic cases) developed later in cosmic history (dubbed “downsizing”), although the reasons for and implications of this effect are debated. CfA astronomers Eleni Kalfontzou, Francesca Civano, Martin Elvis and Paul Green and a colleague have just published the largest study of X-ray selected AGN in the universe from the time when it was only 2.5 billion years old, with the most distant AGN in their sample dating from when the universe was about 1.2 billion years old.

    The astronomers studied 209 AGN detected with the Chandra X-ray Observatory.

    NASA Chandra Telescope

    A multicolor image of galaxies in the field of the Chandra Cosmic Evolution Survey. A large, new study of 209 galaxies in the early universe with X-ray bright supermassive black holes finds that more modest AGN tend to peak later in cosmic history, and that obscured and unobscured AGN evolve in similar ways.
    X-ray: NASA/CXC/SAO/F.Civano et al. Optical: NASA/STScI

    They note that the X-ray observations are less contaminated by host galaxy emission than optical surveys, and consequently that they span a wider, more representative range of physical conditions. The team’s analysis confirms the proposed trend towards downsizing, while it also can effectively rule out some alternative proposals. The scientists also find, among other things, that this sample of AGN represents nuclei with a wide range of molecular gas and dust extinction. Combined with the range of AGN dates, this result enables them to conclude that obscured and unobscured phases of AGN evolve in similar ways.

    See the full article here.

    The Center for Astrophysics combines the resources and research facilities of the Harvard College Observatory and the Smithsonian Astrophysical Observatory under a single director to pursue studies of those basic physical processes that determine the nature and evolution of the universe. The Smithsonian Astrophysical Observatory (SAO) is a bureau of the Smithsonian Institution, founded in 1890. The Harvard College Observatory (HCO), founded in 1839, is a research institution of the Faculty of Arts and Sciences, Harvard University, and provides facilities and substantial other support for teaching activities of the Department of Astronomy.

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  • richardmitnick 10:43 am on October 24, 2014 Permalink | Reply
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    From astrobio.net: “The Abundance of Water in Asteroid Fragments” 

    Astrobiology Magazine

    Astrobiology Magazine

    Oct 24, 2014
    Aaron L. Gronstal

    A new study could provide insights about the abundance of water in fragments from a famous asteroid.

    These colorful images are of thin slices of meteorites viewed through a polarizing microscope. Part of the group classified as HED meteorites for their mineral content (Howardite, Eucrite, Diogenite), they likely fell to Earth from 4 Vesta. Credit: NASA / JPL-Caltech / Hap McSween (Univ. Tennessee), A. Beck and T. McCoy (Smithsonian Inst.)

    The study focused on a mineral called apatite, which can act as a record of the volatiles in materials, including things like magma and lunar rocks. Volatiles are chemical elements with low boiling points (like water), and are usually associated with a celestial bodies’ crust or atmosphere.

    By looking at the apatite in meteorites, the team was able to determine the history of water in these rocks from space.

    The meteorites they chose to study are known as the Howardite-Eucrite-Diogenite (HED) meteorites. These meteorites are a subset of the achondrite meteorites, which are stony meteorites that do not have any chondrites (round grains that were formed from molten droplets of material floating around in space before being incorporated into an asteroid).

    Vesta closeup. Credit: NASA

    Studying the composition of meteorites can provide important clues about how asteroids and other rocky bodies form and evolve. Volatile elements influence processes important to planet formation, such as melting and eruption processes.

    HED meteorites are especially interesting because scientists think they originated from the crust of the asteroid Vesta – a large body in the main asteroid belt that was recently visited by NASA’s Dawn spacecraft. Behind Ceres, Vesta is the second largest object in the asteroid belt and is sometimes referred to as a protoplanet.

    Vesta is a relic of the ancient Solar System and can help astrobiologists understand our system’s formation and evolution. This information provides clues about conditions in the Solar System that led to the formation of a habitable planet – the Earth.

    Interestingly, the team’s results from the HED meteorites are similar to studies on the Earth and Moon, and could support theories that water in all three objects (Vesta, the Earth, and the Moon) came from the same source.

    See the full article here.


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  • richardmitnick 9:42 am on October 24, 2014 Permalink | Reply
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    From SPACE.com: “Einstein’s Gravity Waves Could Be Found with New Method” 

    space-dot-com logo


    October 24, 2014
    Charles Q. Choi

    Gravitational waves, invisible ripples in the fabric of space and time, might be detected by looking for the brightening of stars, researchers say.

    This illustration depicts the gravitational waves generated by two black holes orbiting each other.
    Credit: NASA

    These mysterious ripples were first proposed by Albert Einstein as part of his theory of general relativity. The waves’ size depends on the mass of the objects creating them.

    “Gravitational waves are emitted by accelerating masses,” said lead study author Barry McKernan, an astrophysicist at the American Museum of Natural History in New York. Really big waves are emitted by really big masses, such as systems containing black holes merging with each other.

    Scientists have still not made direct observations of gravitational waves, although researchers continue to endeavor to detect them using experiments involving lasers on the ground and in space. The waves interact very weakly with matter, which partly explains why seeing these ripples in spacetime is difficult.

    Now, McKernan and his colleagues suggest that gravitational waves could have more of an effect on matter than previously thought, with their influence potentially brightening stars.

    “It’s neat that nearly 100 years after Einstein proposed his theory of general relativity, there are still interesting surprises it can turn up,” McKernan told Space.com. “We’re brought up as astronomers thinking the interaction between matter and gravitational waves is very weak, essentially negligible, and that turns out not to be true.”

    The researchers suggest that stars that vibrate at the same frequency as gravitational waves passing through them can absorb a large amount of energy from the ripples.

    “You can imagine gravitational waves as sounds from a piano, and stars as a vibrating violin string held near that piano,” McKernan said. “If the frequency of the sounds matches the frequency of the violin string, the string can resonate with the sound.” If a star gets pumped up with large amounts of energy from gravitational waves in this way, “the star can puff up and look brighter than it normally would,” McKernan said.

    One challenge is determining whether any star brightening astronomers detect is from gravitational waves or some other factor. The researchers suggest the key to spotting the effects of gravitational waves involves looking at large groups of stars.

    “When a population of stars is near a system of merging black holes and is getting pounded by gravitational waves, we think that the more massive stars will light up first,” McKernan said. “It’s like playing keys on a piano and starting with low pitches.” As the black holes get closer together, the frequency of the gravitational waves they generate will increase, “and we’d expect to see brightening of smaller stars,” he added. “If we see a population of stars where the smaller stars are brightening after the bigger stars in a collective way, that might be a sign of gravitational waves.”

    This research also suggests a different way to indirectly detect gravitational waves. If scientists develop working gravitational wave detectors on Earth or in space, when a star passes in front of powerful sources of gravitational waves such as merging black holes, the detector may see a drop in the intensity of those waves. This will happen if the eclipsing star is vibrating at the right frequency.

    “You usually think of stars as being eclipsed by something, not the other way around,” McKernan said in a statement.

    McKernan and his colleagues Saavik Ford, Bence Kocsis and Zoltan Haiman detailed their findings online Sept. 22 in the journal Monthly Notices of the Royal Astronomical Society: Letters.

    See the full article here.

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  • richardmitnick 9:20 am on October 24, 2014 Permalink | Reply
    Tags: , , , , , , POLARBEAR Collaboration   

    From phys.org: “POLARBEAR detects curls in the universe’s oldest light” 


    Oct 21, 2014
    Susan Brown

    Cosmologists have made the most sensitive and precise measurements yet of the polarization of the cosmic microwave background.


    The report, published October 20 in the Astrophysical Journal, marks an early success for POLARBEAR, a collaboration of more than 70 scientists using a telescope high in Chile’s Atacama desert designed to capture the universe’s oldest light.

    “It’s a really important milestone,” said Kam Arnold, the corresponding author of the report who has been working on the instrument for a decade. “We’re in a new regime of more powerful, precision cosmology.” Arnold is a research scientist at UC San Diego’s Center for Astrophysics and Space Sciences and part of the cosmology group led by physics professor Brian Keating.

    POLARBEAR measures remnant radiation from the Big Bang, which has cooled and stretched with the expansion of the universe to microwave lengths. This cosmic microwave background, the CMB, acts as an enormous backlight, illuminating the large-scale structure of the universe and carrying an imprint of cosmic history.

    Cosmic Background Radiation Planck
    CMB from Planck

    Arnold and many others have developed sensitive instruments called bolometers to measure this light. Arrayed in the telescope, the bolometers record the direction of the light’s electrical field from multiple points in the sky.

    “It’s a map of all these little directions that the light’s electric field is pointing,” Arnold explained.

    POLARBEAR has now mapped these angles with resolution on a scale of about 3 arcminutes, just one-tenth the diameter of the full moon..

    The team found telling twists called B-Modes in the patterns of polarization, signs that this cosmic backlight has been warped by intervening structures in the universe, including such mysteries as dark matter, composed of substance that remains unknown, and the famously aloof particles called neutrinos, which elude capture making them difficult to study.

    This initial report, the result of the first season of observation, maps B-modes in three small patches of sky.

    Dust in our own galaxy also emits polarized radiation like the CMB and has influenced other measurements. But these patches are relatively clean, Arnold says. And variations in the CMB polarization due to dust occur on so broad a scale that they do not significantly influence the finer resolution B-modes in this report.

    “We are confident that these B-modes are cosmological rather than galactic in origin,” Arnold said.

    Observations continue, and the data stream will ultimately be fed by additional telescopes comprising the Simons Array. Together they will map wider swaths of the sky, making fundamental discoveries possible.

    Simmons Array

    “POLARBEAR is a real tour de force. With a relatively small, but strong, UC-led team we have surpassed the next-nearest competitors by an order of magnitude in sensitivity. We have paved the way towards solving the deepest mysteries in the quest to understand matter and energy at the beginning of time,” said Brian Keating.

    POLARBEAR is a collaboration of scientists from many institutions including experiment founder, Adrian Lee, professor of physics at UC Berkeley.

    See the full article here.

    About Phys.org in 100 Words

    Phys.org™ (formerly Physorg.com) is a leading web-based science, research and technology news service which covers a full range of topics. These include physics, earth science, medicine, nanotechnology, electronics, space, biology, chemistry, computer sciences, engineering, mathematics and other sciences and technologies. Launched in 2004, Phys.org’s readership has grown steadily to include 1.75 million scientists, researchers, and engineers every month. Phys.org publishes approximately 100 quality articles every day, offering some of the most comprehensive coverage of sci-tech developments world-wide. Quancast 2009 includes Phys.org in its list of the Global Top 2,000 Websites. Phys.org community members enjoy access to many personalized features such as social networking, a personal home page set-up, RSS/XML feeds, article comments and ranking, the ability to save favorite articles, a daily newsletter, and other options.

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