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  • richardmitnick 12:11 pm on November 19, 2015 Permalink | Reply
    Tags: , , , Neutrinos,   

    From Physics: “Synopsis: LHC Data Might Reveal Nature of Neutrinos” 

    Physics LogoAbout Physics

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    November 18, 2015
    Michael Schirber


    As recognized by this year’s Nobel Prize in physics, evidence now points to neutrinos having mass (see 7 October 2015 Focus story). But this opens up new questions about why the neutrino mass is so much smaller than other particle masses. One solution is to assume that the neutrino is a different kind of particle—one that is its own antiparticle. A new theoretical study shows that observations of W boson decays at the Large Hadron Collider (LHC) in Geneva could potentially uncover the antiparticle nature of the neutrino.

    Electrons, protons, and other fermions are Dirac particles, meaning they have a separate antiparticle with the same mass, but opposite charge. Neutrinos could be Dirac particles, but because they have no electric charge, they could also be Majorana particles, for which particle and antiparticle are the same thing. Such Majorana models are attractive because they offer a fairly natural explanation for the extremely small neutrino mass.

    Experiments looking at extremely rare nuclear decays are trying to detect a possible Majorana or Dirac signature of the neutrino. To widen the search, Claudio Dib from Santa María University in Chile and Choong Sun Kim from Yonsei University in Korea propose looking at W boson decays. They considered decays that result in specific combinations of electrons, muons, and neutrinos. These decays have yet to be observed, but they are predicted in theories involving hypothetical sterile neutrinos. Taking into account current limits on the existence of sterile neutrinos, the team predicts that the next runs at the LHC could produce as many as a few thousand of the desired W boson decays. If this count is correct, then physicists should be able to discriminate Majorana from Dirac neutrinos by the shape of the energy spectrum of the outgoing muons.

    This research is published in Physical Review D.

    See the full article here .

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    Physicists are drowning in a flood of research papers in their own fields and coping with an even larger deluge in other areas of physics. How can an active researcher stay informed about the most important developments in physics? Physics highlights a selection of papers from the Physical Review journals. In consultation with expert scientists, the editors choose these papers for their importance and/or intrinsic interest. To highlight these papers, Physics features three kinds of articles: Viewpoints are commentaries written by active researchers, who are asked to explain the results to physicists in other subfields. Focus stories are written by professional science writers in a journalistic style and are intended to be accessible to students and non-experts. Synopses are brief editor-written summaries. Physics provides a much-needed guide to the best in physics, and we welcome your comments (physics@aps.org).

  • richardmitnick 1:04 pm on November 17, 2015 Permalink | Reply
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    From FNAL- “PIP-II: Renewing Fermilab’s accelerator complex” 

    FNAL II photo

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

    Nov. 17, 2015
    Ali Sundermier

    The PIP-II accelerator will provide Fermilab with the high-power beams needed to carry out a world-class neutrino program. Image: Fermilab

    Even accelerator complexes can use some good, old-fashioned makeovers every now and then. The Proton Improvement Plan II, or PIP-II, is a proposed project to improve Fermilab’s particle accelerator complex with a major hardware overhaul and a powerful boost in its capabilities.

    “Every forefront research facility has to be continually renewing itself,” said Steve Holmes, project manager for PIP-II. “Yesterday’s performance is not going to be competitive tomorrow. We’ve done a lot with the Fermilab accelerator complex over the years, but eventually you reach a point where you’ve got to retire some of the really old stuff.”

    The headliner for this upgrade is neutrino physics, Holmes said. The next generation of neutrino programs is going to be bigger and more capable than current experiments. With more beam power, Holmes said, the physics reach will be substantial. When PIP-II achieves its design goal, it will deliver the world’s most intense neutrino beam just in time for the Long-Baseline Neutrino Facility to start operations in 2025. The facility will support Fermilab’s flagship research program, the Deep Underground Neutrino Experiment.

    “We want high power to support our neutrino program,” said Paul Derwent, deputy project manager. “That means lots of particles at high energy and frequently. To increase the power, we need to be able to increase the number of particles right from beginning.”

    PIP-II will allow physicists to accelerate more protons and help them achieve higher energy over a shorter distance. The project will involve retiring Fermilab’s 400-MeV copper linac and building a new 800-MeV superconducting radio-frequency linac as well as replacing the beam transport to the Booster. There will also be upgrades to the laboratory’s Booster, Main Injector and Recycler.

    The most ambitious part of the PIP-II upgrade will be the new 800-MeV linear accelerator, which will be built in the infield of the decommissioned Tevatron accelerator and take advantage of significant existing accelerator infrastructure at Fermilab. The location will provide access to existing utilities, while allowing construction to proceed independent of ongoing accelerator operations and retaining possibilities for upgrade paths down the road. The linac design also provides an option for continuous-wave operations, which means delivery of an uninterrupted, rather than pulsed, stream of particles, providing physicists with more beam for other experiments, such as Mu2e.

    A large part of this effort involves an international collaboration with India. The Department of Atomic Energy in India has offered to contribute hardware in exchange for the experience of building high-intensity superconducting radio-frequency proton linacs, which they hope to construct in their own country.

    “I’m excited to have the chance to retire a bunch of accelerators that were old when I started here 30 years ago,” Holmes joked. “But more seriously, what I find most attractive about this project is the opportunity to do something that will improve the performance of the Fermilab accelerator complex in a manner that will allow us to remain at the forefront both of accelerator-based neutrino physics and our other programs for decades.”

    See the full article here .

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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 1:22 pm on November 13, 2015 Permalink | Reply
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    From BNL: “Neutrino Researchers Win ‘Breakthrough Prize’ in Fundamental Physics” 

    Brookhaven Lab

    November 9, 2015
    Karen McNulty Walsh, (631) 344-8350
    Peter Genzer, (631) 344-3174

    Temp 1

    Bird’s-eye view of the underground Daya Bay Far Hall during installation. The four antineutrino detectors are immersed in a large pool filled with ultra pure water as a cosmic muon veto system. (Photo by Roy Kaltschmidt, Berkeley Lab)

    Five experiments conducting research on the subtle transformations of ghostlike subatomic neutrinos have been awarded the 2016 “Breakthrough Prize” in fundamental physics. The prize, founded in 2012 by a group of Silicon Valley innovators, recognizes profound contributions to human knowledge while working on the deepest mysteries of the universe. Additional prizes were awarded in life sciences and mathematics.

    The $3 million award will be shared equally among researchers from Daya Bay, KamLAND, K2K/T2K, Sudbury Neutrino Observatory (SNO), and Super-Kamiokande (Super-K). Researchers from the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory have made important contributions to the work at several of these experiments, including T2K, SNO and Super-K (the latter two having been honored with this year’s Nobel Prize in physics), and have a large and ongoing involvement in the Daya Bay Collaboration.


    T2K Experiment


    Daya Bay’s founding co-spokespersons—Kam-Biu Luk of the U.S. Department of Energy’s (DOE) Lawrence Berkeley National Laboratory and Yifang Wang of China’s Institute of High Energy Physics (IHEP) in Bejing—and this year’s Nobel laureates—Takaaki Kajita (Super-K) and Arthur B. McDonald (SNO)—were among those in attendance at the Breakthrough Prize award ceremony, broadcast live on the National Geographic Channel last night, to accept the prize on behalf of their collaborations.

    “This is a wonderful honor for all neutrino researchers,” said Brookhaven Lab Director Doon Gibbs. “With this year’s Nobel Prize in physics also being awarded for neutrino research, perhaps 2015 should be renamed the year of the neutrino!”

    Brookhaven and the Daya Bay Experiment

    Neutrinos are elusive particles that flooded the universe in the earliest moments after the Big Bang. Today they are continually produced in the hearts of stars and other nuclear reactions, vastly outnumbering all other particles of matter. Untouched by electromagnetism, they respond only to the weak nuclear force and even weaker gravity, passing mostly unhindered through everything from planets to people.

    Some members of the current Brookhaven Lab Daya Bay team: (seated, from left) Penka Novakova, Laurie Littenberg, Steve Kettell, Ralph Brown (now deceased), and Bob Hackenburg; (standing, from left) Zhe Wang, Chao Zhang, Jiajie Ling, David Jaffe, Brett Viren, Wanda Beriguete, Ron Gill, Mary Bishai, Richard Rosero, Sunej Hans, and Milind Diwan. Missing from the picture are: Donna Barci, Wai-Ting Chan, Chellis Chasman (retired), Dick Hahn (retired), Jyoti Joshi, Debbie Kerr, Michael Mooney, Hide Tanaka, Wei Tang, Xin Qian, Minfang Yeh, and Elizabeth Worcester.

    The challenge of capturing these elusive particles inspired the Daya Bay Collaboration to design and precisely place its detectors at varying distances from the powerful nuclear reactors of the China Guangdong Nuclear Power Group. These reactors, at Daya Bay and nearby Ling Ao, produce 3500 billion billion elusive electron antineutrinos every second.

    Brookhaven scientists led the collaboration’s detector engineering and design efforts, and developed software and analysis techniques for measuring neutrino oscillations. They perfected the “recipe” for a very special, chemically stable liquid that fills Daya Bay’s detectors and interacts with the antineutrinos.

    In 2012, the Daya Bay Collaboration published its first results, announcing the discovery of a new kind of neutrino oscillation with a measurement of how often electron antineutrinos mix and change into other neutrinos. Oscillations are the ways that neutrinos switch their identities among three known “flavors”—electron, muon, and tau—a complex behavior that may ultimately offer insight into why there is far more ordinary matter than antimatter in the universe today.

    In September 2015, the collaboration published their highest-precision results to date, including measurement of the oscillation frequency. Oscillation frequency, in turn, offers insight into the different masses neutrinos can have—a significant detail considering that neutrinos were once thought to be massless. These results are critical to scientists’ understanding of neutrino oscillations and whether their current model of three-neutrino oscillations is correct. The work has also opened the door to using neutrinos to explore potential differences between matter and antimatter that might explain why the universe—created with equal parts matter and antimatter—is filled mostly with matter today.

    “Beginning with the hypothesized existence of the neutrino nearly one hundred years ago, the exploration of the properties of neutrinos has been accomplished with a series of impressive breakthroughs in experimental technique,” said Brookhaven physicist and Daya Bay collaborator David Jaffe. “For Daya Bay to be recognized for our successful measurement of a new kind of neutrino oscillation is an inspiration and an honor.”

    The Breakthrough Prizes

    The Breakthrough Prizes were founded by Silicon Valley innovators Sergey Brin (Google) and Anne Wojcicki (23andMe), Jack Ma (Alibaba) and Cathy Zhang, Yuri Milner (DST Global) and Julia Milner, and Mark Zuckerberg (Facebook) and Priscilla Chan. For the past three years, the Breakthrough Prize has been honoring those at the forefront of the fundamental physics, life sciences and mathematics fields, while also aiming to inspire innovators in these fields for the future.

    This year’s Prizes were announced at a Silicon Valley ceremony hosted by Emmy-nominated “Cosmos” executive producer and “Family Guy” creator Seth MacFarlane, broadcast live on the National Geographic Channel and FOX network on Sunday, November 8, at 10 p.m. U.S. Eastern Time. A one-hour version of the ceremony is scheduled to air on FOX on Sunday, November 29, 7-8 p.m. Eastern Time. The one-hour version will also air globally on the National Geographic Channel in 171 countries and 45 languages.

    Brookhaven’s participation in the Daya Bay Collaboration is funded by the DOE Office of Science (HEP, NP).

    See the full article here .

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    BNL Campus

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

  • richardmitnick 11:40 am on November 12, 2015 Permalink | Reply
    Tags: , , , Neutrinos,   

    From physicsworld.com: “Gran Sasso steps up the hunt for missing particles” 


    Nov 11, 2015
    Edwin Cartlidge


    Physicists working at the Gran Sasso National Laboratory in central Italy, located 1400 m under the mountain of the same name, are soon to start taking data from two new experiments.

    INFN Gran Sasso ICARUS
    Gran Sasso

    Each facility will target a different kind of missing matter: one will search for dark matter while the other will try and detect absent neutrinos to prove that neutrinos are their own antiparticle.

    Dark flash

    The hunt for dark matter – the mysterious substance believed to make up about 80% of all matter in the universe but not yet detected directly – will be carried out using XENON1T. This experiment, which was inaugurated at an event at Gran Sasso today, consists of 3.5 tonnes of liquid xenon. It is designed to measure very faint flashes of light that are given off whenever particles from the dark matter halo of the Milky Way collide with the xenon nuclei. The xenon will be stored at a temperature of about –100 °C in a cryostat and surrounded by a tank containing some 700 tonnes of purified water to minimize background radioactivity.

    Run by an international collaboration of 120 students and scientists from more than 2 institutions, XENON1T is expected to be about 100 times more sensitive than its 160 kg predecessor experiment and around 40 times better than the world’s current leading dark-matter detector – the 370 kg Large Underground Xenon experiment in South Dakota, US.

    LUX Dark matter

    Due to start taking data by the end of March next year, XENON1T will either detect dark matter or place severe constraints on the properties of theoretically-favoured weakly interacting massive particles (WIMPs), says collaboration spokesperson Elena Aprile of Columbia University in New York.

    Dark heart

    The other new experiment at Gran Sasso is the Cryogenic Underground Observatory for Rare Events (CUORE), which will look for an extremely rare nuclear process known as neutrinoless double beta decay.

    CUORE experiment

    That decay, if it exists, would involve two neutrons in certain nuclei decaying simultaneously into two protons while emitting two electrons but no antineutrinos (unlike normal beta decay), implying that the neutrino is its own antiparticle. Due to turn on early next year, CUORE will measure the energy spectrum of electrons emitted by 741 kg of tellurium dioxide surrounded by radioactively inert lead blocks recovered from a Roman ship that sank 2000 years ago.

    Meanwhile, towards the end of 2016 another group of scientists at Gran Sasso should take delivery of about a kilogram of cerium oxide powder, which they will place several metres below the Borexino neutrino detector.

    Borexino Solar Neutrino detector

    The Short Distance Neutrino Oscillations with BoreXino (SOX) experiment will look for a sinusoidal-like variation in the number of interactions generated within the detector by neutrinos from the radioactive cerium. SOX leader Marco Pallavicini of the University of Genoa says that such a variation would be a sure sign of “sterile” neutrinos – hypothetical particles outside the Standard Model of particle physics that would “oscillate” into ordinary neutrinos but would not interact with any other kind of matter.

    See the full article here .

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  • richardmitnick 7:40 am on November 3, 2015 Permalink | Reply
    Tags: , , Neutrinos   

    From FNAL: “MicroBooNE sees first accelerator-born neutrinos” 

    FNAL II photo

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

    Nov. 2, 2015
    Chris Patrick

    This display shows a neutrino event candidate in the MicroBooNE detector. Image: MicroBooNE

    Today the MicroBooNE collaboration announced that it has seen its first neutrinos in the experiment’s newly built detector.

    FNAL Microboone
    Microboone Detector

    “It’s nine years since we proposed, designed, built, assembled and commissioned this experiment,” said Bonnie Fleming, MicroBooNE co-spokesperson and a professor of physics at Yale University. “That kind of investment makes seeing first neutrinos incredible.”

    After months of hard work and improvements by the Fermilab Booster team, on Oct. 15, the Fermilab accelerator complex began delivering protons, which are used to make neutrinos, to one of the laboratory’s newest neutrino experiments, MicroBooNE. After the beam was turned on, scientists analyzed the data recorded by MicroBooNE’s particle detector to find evidence of its first neutrino interactions.

    “This was a big team effort,” said Anne Schukraft, Fermilab postdoc working on MicroBooNE. “More than 100 people have been working very hard to make this happen. It’s exciting to see the first neutrinos.”

    MicroBooNE’s detector is a liquid-argon time projection chamber. It resembles a silo lying on its side, but instead of grain, it’s filled with 170 tons of liquid argon.

    Liquid argon is 40 percent denser than water, and hence neutrinos are more likely to interact with it. When an accelerator-born neutrino hits the nucleus of an argon atom in the detector, its collision creates a spray of subatomic particle debris. Tracking these particles allows scientists to reveal the type and properties of the neutrino that produced them.

    Neutrinos have recently received quite a bit of media attention. The 2015 Nobel Prize in physics was awarded for neutrino oscillations, a phenomenon that is of great importance to the field of elementary particle physics. Intense activity is under way worldwide to capture neutrinos and examine their behavior of transforming from one type into another.

    MicroBooNE is an example of a new liquid-argon detector being developed to further probe this phenomenon while reconstructing the particle tracks emerging from neutrino collisions as finely detailed three-dimensional images. Its findings will be relevant for the forthcoming Deep Underground Neutrino Experiment, known as DUNE, which plans to examine neutrino transitions over longer distances and a much broader energy range. Scientists are also using MicroBooNE as an R&D platform for the large DUNE liquid-argon detectors.

    FNAL Dune & LBNF

    “Future neutrino experiments will use this technology,” said Sam Zeller, Fermilab physicist and MicroBooNE co-spokesperson. “We’re learning a lot from this detector. It’s important not just for us, but for the entire neutrino community.”

    In August, MicroBooNE saw its first cosmic ray events, recording the tracks of cosmic ray muons. The recent neutrino sighting brings MicroBooNE researchers much closer to one of their scientific goals, determining whether the excess of low-energy events observed in a previous Fermilab experiment was the footprint of a sterile neutrino or a new type of background.

    Before they can do that, however, MicroBooNE will have to collect data for several years.

    During this time, MicroBooNE will also be the first liquid-argon detector to measure neutrino interactions from a beam of such low energy. At less than 800 MeV (megaelectronvolts), this beam produces the lowest-energy neutrinos yet to be observed with a liquid-argon detector.

    MicroBooNE is part of Fermilab’s Short-Baseline Neutrino program, and scientists will eventually add two more detectors (ICARUS and the Short-Baseline Near Detector) to its neutrino beamline.


    See the full article here .

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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 10:15 am on October 21, 2015 Permalink | Reply
    Tags: Art McDonald, , Neutrinos,   

    From NYT: “Struggling to Get a Handle on the Flavorful Neutrino” 

    New York Times

    The New York Times

    OCT. 19, 2015
    George Johnson

    Chad Hagen

    It was 20 years ago that Art McDonald and I stopped at a Tim Hortons near Sudbury, Ontario, for coffee and doughnuts on our way to his job at the neutrino mine.

    Art McDonald

    Donning hard hats, we crowded into a rattling elevator cage and descended 6,800 feet to an underground laboratory that reminded me of the one in The Andromeda Strain.

    The Sudbury Neutrino Observatory sat at the end of a long corridor at the bottom of a working nickel mine.

    Sudbury Neutrino Observatory
    Sudbury Neutrino Observatory

    In the tunnels above us miners dug and blasted through granite. Dr. McDonald was after a far less substantial ore.

    Neutrinos are said to pass through Earth almost as easily as through empty space. During the flight, theorists believed, neutrinos were capable of changing their identity. Dr. McDonald’s job was to catch them in the act. It was six more years before he succeeded. Earlier this month he won a share of a Nobel Prize, a climax to a long and perplexing tale.

    I had come to Sudbury on a philosophical quest. I wasn’t entirely sure I believed in neutrinos, which were invented [? how about “theorized”] in 1930 to fill a hole in physics. In a type of radioactive decay, experimenters had measured more energy going in than coming out.

    That is supposed to be impossible, so the fix was to conjure forth an unseen particle with precisely the right characteristics to take up the slack. The particles had gone unnoticed, the argument went, because they had no handles for experimenters to grab onto — no charge and (it was believed at the time) no mass.

    Sometimes this explanation seemed a little too pat. I knew neutrinos were eventually detected, but in ways so oblique that I wondered how physicists could be sure they weren’t just seeing what they needed to see.

    By now neutrinos are woven so tightly into the mesh of physics that you would have to be a crank to doubt their existence. But when you start peeling away the layers of theory, reality can start feeling pretty abstract.

    Of all the particles in the universe, the only ones our senses can directly register are photons — particles of light that strike the retina and send electrical signals to the brain. Our cruder senses respond to whole globs of matter — larger globs for touch, invisibly tiny globs for smell. Sound, for its part, is the vibration of matter, a rumbling of the ground or a reverberation of the air.

    Revealing the existence of theoretical stuff like neutrinos means coaxing them into producing photons to be registered by our eyes or our instruments. It took a quarter century to figure out how to do that, and by a somewhat circuitous route.

    Like other particles, neutrinos, the theory goes, have antimatter counterparts. When an antineutrino collides with a proton, it should transform it into a neutron while an antimatter electron is kicked out. It quickly strikes a regular electron, exploding into two photons flying in opposite directions — tiny flashes of light.

    An instant later the neutron is sucked into the core of an atom, resulting in another flash. If the timing and energy of these scintillations are precisely in sync, you can say you have glimpsed a neutrino.

    In the mid-1950s two experimenters, Frederick Reines and Clyde Cowan, put it all together. They measured neutrinos spewing from a nuclear reactor. The reward was a Nobel Prize.

    Then things started getting messy. Now that it was possible to detect neutrinos, physicists had a way of testing their theory of sunlight — that it was generated by nuclear fusion. That meant neutrinos should be pouring from the sun in droves.

    In the inverse of the reaction used by Reines and Cowan, a neutrino striking a neutron should transform it into a proton and an electron. If the neutron is contained within the core of a chlorine atom, it morphs into an argon atom and emits gamma rays. Gamma rays are very high frequency light.

    With a vat of chlorine atoms (in the form of dry cleaning fluid), Raymond Davis Jr. was first to find this circumstantial evidence (resulting in yet another Nobel Prize). But his experiment is more famous for seeing only a fraction of the neutrinos required by solar theory — another hole in physics.

    Maybe the sun wasn’t really powered by fusion. Or maybe neutrinos were eaten by a black hole lurking inside. By the time I met Dr. McDonald, theorists had rallied around a less radical thought.

    By then there seemed to be three different “flavors” of neutrinos. Maybe as neutrinos streamed from the sun, they “oscillated” between the different types. Our instruments had been blind to all but one. That is where the Sudbury detector came in. It succeeded in registering all three flavors, as signatures of photons.

    This solution to the solar neutrino problem required a troubling trade-off. For years physicists had celebrated the neutrino’s massless purity, which allowed it to pass at lightspeed through anything in its path. But for neutrinos to oscillate they had to be saddled with a tiny dab of mass. “That can’t be — it’s too ugly,” the great physicist Hans Bethe remarked when he heard the proposal. But in the end the alternatives seemed worse.

    As I raise a doughnut and a cup of takeout coffee to Dr. McDonald and his crew, I still feel a little uneasy. Quarks, gluons, Higgs bosons — the story is the same. Behind the scenes, particles decay into other particles, until at the end of the tunnel you see the light. Whether we’re reading a meter or a computer screen, our knowledge ultimately comes down to photons.

    On that trip to Sudbury, Dr. McDonald gave me a nugget of nickel ore. Solid as it seems it is made of atoms that consist mostly of empty space. It shimmers a silvery gold because photons strike hollow shells of electrons and ricochet into my eyes. All of our knowledge of the world is so indirect.

    I find some satisfaction in Boswell’s famous description of Samuel Johnson disputing Bishop Berkeley’s contention that the world is all in our minds. Kicking a rock and maybe stubbing his toe, he declared of the theory, “I refute it thus.”

    See the full article here .

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  • richardmitnick 10:49 am on October 19, 2015 Permalink | Reply
    Tags: , , , Neutrinoless double beta decay, Neutrinos   

    From AAAS: “U.S. nuclear physicists push for new neutrino experiment” 



    15 October 2015
    Adrian Cho

    Researchers assemble a prototype detector for observing a rare form of radioactive decay known as neutrinoless double-beta decay. Physicists hope to scale up to a much larger, tonne-sized detector. Matthew Kapust, Sanford Underground Research Facility.

    The United States should seize the initiative and soon mount a massive experiment to search for a hypothesized type of nuclear decay that is possible only if an elusive, nearly massless particle called the neutrino is—weirdly—its own antiparticle. That’s one of four recommendations in a new long-range plan developed by U.S. nuclear physicists. The plan, presented to a federal advisory panel today in Washington, D.C., will inform planning for the coming decade in the Department of Energy’s (DOE’s) nuclear physics program, and the National Science Foundation’s (NSF’s) physics program. If researchers observe the new decay—and they hope to start work on the experiment within 3 years—the discovery would require rewrites of textbooks in nuclear and particle physics.

    The report, which was unanimously approved by the Nuclear Science Advisory Committee (NSAC), immediately met with praise from DOE officials. “It’s an ambitious plan,” says Patricia Dehmer, acting director of DOE’s $5.1 billion Office of Science, which will spend $596 million this year on its nuclear physics program. “It builds on the past and looks to a very promising future.”

    As expected, the plan also recommended that U.S. nuclear physicists eventually build a new collider, one that would smash a beam of electrons into a beam of protons or heavier atomic nuclei. But the report put no firm timeline on when such an electron-ion collider could be built, and suggested that it could not be completed until the end of the 2020s at the earliest. Still, physicists and DOE officials say that the recommendation—which ranked third in the report—is still notable, because it shows that the U.S. community has come together behind the concept of building such a collider. “I think it’s defining the goal,” Dehmer says.

    The report’s top recommendation, however, is for researchers to first fully exploit the three major facilities U.S. nuclear physicists already have. Physicists at Thomas Jefferson National Accelerator Facility in Newport News, Virginia, are completing a $338 million upgrade to their Continuous Beam Electron Accelerator Facility (CEBAF), which they use primarily to probe the internal structure of protons and neutrons.


    Physicists at Michigan State University in East Lansing are building the $730 million Facility for Rare Isotope Beams (FRIB), a linear accelerator that, when it is completed in 2022, will generate exotic nuclei and study their structure. Finally, since 2000, physicists at Brookhaven National Laboratory [BNL] in Upton, New York, have used their Relativistic Heavy Ion Collider (RHIC) to smash nuclei such as gold together and literally melt the protons and neutrons into an amorphous plasma of their constituents—particles called quarks and gluons—like that that filled the newborn universe.

    Michigan State FRIB
    Michigan State FRIB

    BNL RHIC Campus
    RHIC at BNL

    The new long-range plan calls for running all three facilities for the foreseeable future, even RHIC, which is arguably closest to the end of its life. “What we’re really saying is that we want to run RHIC for another 5 to 7 years,” says Donald Geesaman, a physicist at Argonne National Laboratory in Illinois and chair of NSAC.

    Just 2 years ago, it seemed unlikely that U.S. physicists would be able to run all three of the current facilities. In 2012, facing the prospect of extremely tight budget, DOE tasked NSAC with deciding which facility, CEBAF or RHIC, it would sacrifice if it had to. The following January, physicists reluctantly decided that if forced to chose, they would opt to shut down RHIC. However, since then, DOE’s nuclear physics budget has rebounded sufficiently that now running the three facilities in concert is feasible, even if the budget grows only with inflation over the next several years, the report says. Those budget increases reflect how effectively the community presented its case for avoiding such cuts, says Timothy Hallman, DOE’s associate director for nuclear physics.

    The report’s fourth recommendation is to invest in more small- and mid-scale projects, which have gotten short shrift in recent years. “That was the right thing to do to get FRIB built,” Geesaman says, but now it’s time to correct course.

    Clearly the newest element in the long range plan is the call to move quickly on the search for the rare nuclear decay, which is called neutrinoless double beta decay. “It’s certainly putting [the project] in a different category of probability than it has been in up to this point,” Hallman says.

    In ordinary beta decay, a neutron in a nucleus such as tritium can change into a proton by spitting out an electron and an anti-neutrino. Some nuclei, such as selenium-82, can spit out two electrons and two antineutrinos in so-called double beta decay. But in neutrinoless double beta decay, only two electrons would come out of a nucleus. For that to happen, the neutrino would have to be its own antiparticle, as the antineutrino emitted with one electron would instantly be reabsorbed as a neutrino to trigger emission of the second electron.

    If the neutrino were its own antiparticle, it would be the only building block of matter with that property—although force-carrying particles like the photon gluon are their own antiparticles. It would also mean that the neutrino would have to get its mass in away different from other matter particles, that are weighed down by the so-called Higgs mechanism.

    To spot such rare decay—if it exists—physicists need to work far underground, where background radiation is low, and to observe large amount of nuclei, such as xenon-136, germanium-76, or tellurium-130. Physicists around the world are already working on experiments using several kilogram of such material. But spotting the decay will likely take a tonne-scale experiment, and the report calls on the U.S. to start building one as soon as 2018. “The neutrinoless double beta decay arena is very competitive internationally,” says Robert McKeown, a physicists at Jefferson Lab. “If the U.S. wants to lead we can’t wait.” A tonne-scale experiment is likely to cost a few hundred million dollars.

    Fulfilling the plan may not be easy. It assumes the nuclear physics budget will increase by 1.6% above inflation each of the next 10 years—or at an absolute rate of between 3.5% and 4%. That’s a tall order, Dehmer cautioned at the advisory panel meeting. Still, she noted, the nuclear physics community has done about that well since it presented its last long-range plan in 2007. Dehmer credited that budgetary success in part to the community’s willingness to embrace such plans—something that physicists in other field sometimes struggle to do.

    See the full article here .

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  • richardmitnick 3:21 pm on October 8, 2015 Permalink | Reply
    Tags: , Neutrinos,   

    From The Conversation: “How neutrinos, which barely exist, just ran off with another Nobel Prize” 

    The Conversation

    October 6, 2015
    John Beacom

    Super-Kamiokande Detector
    Super-Kamiokande Detector

    Neutrinos take patience. They’re worth it, and the announcement of the 2015 Nobel Prize in Physics recognizes that, following related prizes in 1988, 1995 and 2002. Ironically, these near-undetectable particles can reveal things that cannot be seen any other way.

    I could begin by telling you that neutrinos are elementary particles, but that sounds condescending. They’re not called elementary because they’re easy to understand – they aren’t – but because they are seemingly point-like in size, and we can’t break them down into smaller constituents. There’s no such thing as half a neutrino.

    The smallest things in the universe

    Atoms, despite the Greek name (“cannot be cut”), are not elementary particles, meaning they can be disassembled. An atom is a diffuse cloud of electrons surrounding a tiny, dense nucleus composed of protons and neutrons, which can be broken into up and down quarks.

    Particle colliders, which accelerate particles to near the speed of light and smash them together, help us discover new elementary particles. First, because of E = mc2, the energy in the collision can be converted into the mass of particles. Second, the higher the accelerator’s beam energy, the more finely we can resolve composite structures, just as we can see smaller things with X-rays than with visible light.

    We haven’t been able to take apart electrons or quarks. These are elementary particles, forming the basic constituents of ordinary matter: the Lego bricks of the universe. Interestingly, there are many heavy cousins of familiar particles that exist only for fractions of a second, and thus are not part of ordinary matter. For example, for electrons these are the muon and tauon.

    Standard Model of elementary particles, of which neutrinos are one kind. MissMJ, CC BY

    What’s a neutrino?

    How is this elementary particle – the neutrino – different from all other elementary particles? It’s unique in that it’s both almost massless and almost noninteracting. Those features are different, though often conflated (don’t take advice about neutrinos from a poet, even it is John Updike).

    It’s a mystery why neutrinos are almost, but not quite, massless. We do know why they’re almost noninteracting, though: They don’t feel the electromagnetic or strong forces that bind nuclei and atoms, only the aptly named weak force (and gravity, but barely, because their masses are small).

    Though neutrinos are not constituents of ordinary matter, they are everywhere around us – a trillion from the sun pass through your eyes every second. There are hundreds per every cubic centimeter left over from the Big Bang. Because they so rarely interact, it’s almost impossible to observe them, and you certainly don’t feel them.

    Neutrinos have other weird aspects. They come in three types, called flavours electron, muon and tauon neutrinos, corresponding to the three charged particles they pair with – and all of these seem to be stable, unlike the heavy cousins of the electron.

    Because the three flavors of neutrinos are almost identical, there is the theoretical possibility that they could change into each other, which is another unusual aspect of these particles, one that can reveal new physics. This transformation requires three things: that neutrino masses are nonzero, are different for different types, and that neutrinos of definite flavour are quantum combinations of neutrinos of definite mass (this is called “neutrino mixing”).

    For decades, it was generally expected that none of these conditions would be met. Not by neutrino physicists, though – we held out hope.

    Doing astronomy with invisible particles

    In the end, nature provided, and experimentalists discovered, supported by calculations from theorists. First came decades of searching by many experiments, with important hints to encourage the chase.

    Then, in 1998, the Super-Kamiokande experiment in Japan announced strong evidence that muon neutrinos produced in Earth’s atmosphere change to another type (now thought to be tauon neutrinos). The proof was seeing this happen for neutrinos that came from “below,” having traveled a long distance through Earth, but not for those from “above,” having traveled just the short distance through the atmosphere. Because the neutrino flux is (nearly) the same at different places on Earth, this allowed a “before” and “after” measurement.

    View from the bottom of the Sudbury Neutrino Observatory acrylic vessel and PMT array. Ernest Orlando Lawrence Berkeley National Laboratory, CC

    In 2001 and 2002, the Sudbury Neutrino Observatory in Canada announced strong evidence that electron neutrinos produced in the core of the sun also change flavors. This time the proof was seeing that electron flavor neutrinos that disappeared then reappeared as other types (now thought to be a mix of muon and tauon neutrinos).

    Each of those experiments saw about half as many neutrinos as expected from theoretical predictions. And, perhaps fittingly, Takaaki Kajita and Arthur McDonald each got half a Nobel Prize.

    In both cases, quantum-mechanical effects, which normally operate only at microscopic distances, were observed on terrestrial and astronomical distance scales.

    As the front page of The New York Times said in 1998, Mass Found in Elusive Particle; Universe May Never Be the Same. These clear indications of neutrino flavour change, since confirmed and measured in detail in laboratory experiments, show that neutrinos have mass and that these masses are different for different types of neutrino. Interestingly, we don’t yet know what the values of the masses are, though other experiments show that they must be about a million times smaller than the mass of an electron, and perhaps smaller.

    That’s the headline. The rest of the story is that the mixing between different neutrino flavors is in fact quite large. You might think it’s bad news when predictions fail – for example, that we would never be able to observe neutrino flavor change – but this kind of failure is good, because we learn something new.

    Art McDonald after the announcement he’s won the Nobel Prize for Physics. Reuters

    Takaaki Kajita at a news conference after the announcement he’s won the Nobel Prize for Physics. Issei Kato/Reuters

    International society of neutrino hunters

    I’m delighted to see this recognition for my friends Taka and Art. I wish that several key people, both experimentalists and theorists, who contributed in essential ways had been similarly recognized. It took many years to construct and operate those experiments, which themselves built on slow, difficult and largely unrewarding work going back decades, requiring the effort of hundreds of people. That includes major US participation in both Super-Kamiokande and the Sudbury Neutrino Observatory. So, congratulations to neutrinos, to Taka and Art, and to the many others who made this possible!

    When I first started working on neutrinos, over 20 years ago, many people, including prominent scientists, told me I was wasting my time. Later, others urged me to work on something else, because “people who worked on neutrinos don’t get jobs.” And, even now, plenty of physicists and astronomers think we’re chasing something almost imaginary.

    But we’re not. Neutrinos are real. They’re an essential part of physics, shedding light on the origin of mass, the particle-antiparticle asymmetry of the universe, and perhaps the existence of new forces that are too feeble to test with other particles. And they are an essential part of astronomy, revealing the highest-energy accelerators in the Universe, what’s inside the densest stars, and perhaps new and otherwise unseen astrophysical objects.

    Download the mp4 video here.

    Tiny particles, big mysteries

    Why should you care, beyond sharing our curiosity about revealing some of the weirdest things in the universe?

    The weak force that neutrinos feel is what changes protons to neutrons, powering nuclear fusion reactions in the sun and other stars, and creating the elements that make planets and life itself possible.

    Neutrinos are the only component of dark matter that we understand, and figuring out the rest will help us understand the structure and evolution of the universe. If the neutrino masses had been much larger, the universe would look much different, and perhaps we wouldn’t be here to see.

    Finally, if you are purely practical, neutrino physics and astrophysics is one of the most difficult jobs, requiring us to invent incredibly sensitive detectors and techniques. This knowledge has other uses; for example, using a neutrino detector, we could tell if a purported nuclear reactor is on, what its power level is and even if it is producing plutonium. This may have some real-world applications.

    The past decades in neutrino physics and astronomy have been great, but some of the most exciting things are just starting to happen. The IceCube Neutrino Observatory at the South Pole is now seeing high-energy neutrinos from outside our galaxy.

    ICECUBE neutrino detector
    IceCube neutrino detector interior

    Super-Kamiokande has announced a plan, based on a proposal from me and Mark Vagins, to improve their sensitivity to antineutrinos compared to neutrinos. And the international community hopes to build a major new neutrino facility, in which a powerful beam of neutrinos will be sent from Fermilab in Illinois to a detector deep underground in the Homestake mine in South Dakota [Sanford Underground Research Facility, SURF]. Who knows what we’ll find?

    Sanford Underground Research Facility Interior
    Sanford Underground levels

    And that’s what I’ve really been waiting for.

    See the full article here .

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    The Conversation US launched as a pilot project in October 2014. It is an independent source of news and views from the academic and research community, delivered direct to the public.
    Our team of professional editors work with university and research institute experts to unlock their knowledge for use by the wider public.
    Access to independent, high quality, authenticated, explanatory journalism underpins a functioning democracy. Our aim is to promote better understanding of current affairs and complex issues. And hopefully allow for a better quality of public discourse and conversation.

  • richardmitnick 10:44 am on October 8, 2015 Permalink | Reply
    Tags: , , , Neutrinos   

    From BBC: “Supernova ‘stream’ in neutrino lab’s sights” 


    2 October 2015
    Paul Rincon

    A global collaboration will aim to unravel the mysteries of neutrinos – also known as “ghost particles”.

    The Dune collaboration might observe neutrinos from a supernova in our galaxy – if luck is on their side

    Among the goals of the venture, formed earlier this year, will be to catch neutrino particles streaming towards us from a supernova – an exploding star.

    Such events occur about every 30 years, but the neutrino streams they produce have not been studied in detail.

    Dune (Deep Underground Neutrino Experiment) will be hosted at Fermilab in Batavia, Illinois.

    It will involve the development of the world’s most high-intensity beam of neutrinos, which will travel 1,300km (800mi) underground from Fermilab towards a massive detector instrument based at the Sanford Underground Research Facility [SURF] in South Dakota.

    Sanford Underground Research Facility Interior

    The venture is the product of a merger between European and US projects with similar aims. The international collaboration held its inaugural meeting at Fermilab in April.

    “There has been a process since last summer to prepare the ground for this collaboration, based on bringing together the US and European projects. There are now 700 people signed up,” said Prof Stefan Söldner-Rembold, from the University of Manchester.

    “The step forward is a new collaboration with a new name that has commitments from the US, Europe, India and other regions to go forward.”

    Neutrinos are one of some 17 elementary cosmic building blocks that make up the Universe. But they are also a source of intrigue for particle physicists.

    They are extremely light particles, with no electric charge and pass harmlessly through other matter. This property makes them very difficult to observe and is responsible for them being nicknamed “ghost particles”. Neutrinos may also play a role in the mystery of why the Universe came to consist mostly of matter rather than antimatter.


    They are found in three different states, or flavours, and the particles can flip from one flavour to another. Dune aims to carry out a detailed investigation of this three-flavour model of neutrino physics.

    The project will make use of an existing particle accelerator at Fermilab as a proton source, and then smash the beam into a so-called “target” made of a material that will engender the production of short-lived particles. These will travel about 200m through a decay pipe, and as they do, a large proportion will transform into neutrinos.

    Another potential scientific pay-off of the collaboration might be the opportunity to observe an exploding star in closer detail than ever before. But the team will need luck on their side, as it is dependent on a suitable event taking place during the lifetime of the project. It’s a game of chance, but scientists are hopeful the detector will catch one.

    The four 10-kilotonne detector modules will be filled with liquid argon. FNAL

    “If a supernova happens in our galaxy, which should happen once every 30 years or so, this experiment should – within seconds – see thousands of neutrino interactions,” said Prof Söldner-Rembold.

    “There was a supernova in 1987 and there were some neutrino detectors online – they saw something, which spurred a lot of interest at the time.

    This image shows the remnant of Supernova 1987A seen in light of very different wavelengths. ALMA data (in red) shows newly formed dust in the centre of the remnant. Hubble (in green) and Chandra (in blue) data show the expanding shock wave.

    ALMA Array

    NASA Hubble Telescope
    NASA/ESA Hubble

    NASA Chandra Telescope

    But a supernova with a detector like this, it is something that has never been observed.

    The “spillover” from a supernova would depend on how far away it was from Earth. But such an energetic event, close enough to Earth, could potentially send huge numbers of neutrinos streaming our way – to be picked up by detectors. This could potentially shed light on the mechanics of stellar explosions, and how these events evolve over time.

    Dune will also look for a hypothetical phenomenon known as proton decay. Protons are very stable sub-atomic particles; they have never been seen to transform into lighter cosmic building blocks.

    However, in some theories of particle physics, such as the still-unconfirmed framework known as supersymmetry, this should happen.

    “It’s the ultimate rare decay. It’s another way of looking for ‘new physics’, separate from the LHC, where you don’t need to go to high energies,” said Prof Söldner-Rembold.

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

    Cern, the organisation that operates the Large Hadron Collider, is one of those that is now involved with Dune. The cost of the entire project is on the order of $1bn, but some international partners pay through in-kind contributions.

    The detectors will be filled with liquid argon, with the first of the four 10-kilotonne modules due to be installed in the 2020s. Neutrino collisions create electrons and flashes of light in the liquid argon, which leave observable traces of the neutrinos. The project is set to run for three decades.

    See the full article here .

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  • richardmitnick 4:18 pm on October 7, 2015 Permalink | Reply
    Tags: , , , Neutrinos,   

    From DON Lincoln (FNAL) for NOVA: “Neutrino Physicists win Nobel, but Neutrino Mysteries Remain” 



    07 Oct 2015
    FNAL Don Lincoln
    Don Lincoln

    Neutrinos are the most enigmatic of the subatomic fundamental particles. Ghosts of the quantum world, neutrinos interact so weakly with ordinary matter that it would take a wall of solid lead five light-years deep to stop the neutrinos generated by the sun. In awarding this year’s Nobel Prize in physics to Takaaki Kajita (Super-Kamiokande Collaboration/University of Tokyo) and Arthur McDonald (Sudbury Neutrino Observatory Collaboration/Queen’s University, Canada) for their neutrino research, the Nobel committee affirmed just how much these “ghost particles” can teach us about fundamental physics. And we still have much more to learn about neutrinos.

    Super-Kamiokande experiment Japan
    Super-Kamiokande experiment Japan

    Sudbury Neutrino Observatory
    Sudbury Neutrino Observatory

    View from the bottom of the SNO acrylic vessel and photomultiplier tube array with a fish-eye lens. This photo was taken immediately before the final, bottom-most panel of photomultiplier tubes was installed. Photo courtesy of Ernest Orlando, Lawrence Berkeley National Laboratory.

    Neutrinos are quantum chameleons, able to change their identity between the three known species (called electron-, muon– and tau-neutrinos). It’s as if a duck could change itself into a goose and then a swan and back into a duck again. Takaaki Kajita and Arthur B. McDonald received the Nobel for finding the first conclusive proof of this identity-bending behavior.

    In 1970, chemist Ray Davis built a large experiment designed to detect neutrinos from the sun. This detector was made up of a 100,000-gallon tank filled with a chlorine-containing compound. When a neutrino hit a chlorine nucleus, it would convert it into argon. In spite of a flux of about 100,000 trillion solar neutrinos per second, neutrinos interact so rarely that he expected to see only about a couple dozen argon atoms after a week’s running.

    But the experiment found even fewer argon atoms than predicted, and Davis concluded that the flux of electron-type neutrinos hitting his detector was only about a third of that emitted by the sun. This was an incredible scientific achievement and, for it, Davis was awarded a part of the 2002 Nobel Prize in physics.

    Explaining how these neutrinos got “lost” in their journey to Earth would take nearly three decades. The correct answer was put forth by the Italian-born physicist Bruno Pontecorvo, who hypothesized that the electron-type neutrinos emitted by the sun were morphing, or “oscillating,” into muon-type neutrinos. (Note that the tau-type neutrino was postulated in 1975 and observed in 2000; Pontecorvo was unaware of its existence.) This also meant that neutrinos must have mass—a surprise, since even in the Standard Model of particle physics, our most modern theory of the behavior of subatomic particles, neutrinos are treated as massless.

    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.

    So, if neutrinos could really oscillate, we would know that our current theory is wrong, at least in part.

    In 1998, a team of physicists led by Takaaki Kajita was using the Super Kamiokande (SuperK) experiment in Japan to study neutrinos created when cosmic rays from space hit the Earth’s atmosphere. SuperK was an enormous cavern, filled with 50,000 tons of water and surrounded by 11,000 light-detecting devices called phototubes. When a neutrino collided with a water molecule, the resulting debris from the interaction would fly off in the direction that the incident neutrino was traveling. This debris would emit a form of light called Cerenkov radiation and scientists could therefore determine the direction the neutrino was traveling.

    Cherenkov radiation glowing in the core of the Advanced Test Reactor [Idaho National Laboratory].

    By comparing the neutrinos created overhead, about 12 miles from the detector, to those created on the other side of the Earth, about 8,000 miles away, the researchers were able to demonstrate that muon-type neutrinos created in the atmosphere were disappearing, and that the rate of disappearance was related to the distance that the neutrinos traveled before being detected. This was clear evidence for neutrino oscillations.

    Just a few years later, in 2001, the Sudbury Neutrino Observatory (SNO) experiment, led by Arthur B. McDonald, was looking at neutrinos originating in the sun. Unlike previous experiments, the SNO could identify all three neutrino species, thanks to its giant tank of heavy water (i.e. D2O, two deuterium atoms combined with oxygen). SNO first used ordinary water to measure the flux of electron-type neutrinos and then heavy water to observe all three types. The SNO team was able to demonstrate that the neutrino flux of all three types of neutrinos agreed exactly with those emitted by the sun, but that the flux of electron-type was lower than would be expected in a no-oscillation scenario. This experiment was a definitive demonstration of the oscillation of solar neutrinos.

    With the achievements of both the SuperK and SNO experiments, it is entirely fitting that Kajita and McDonald share the 2015 Nobel Prize in physics. They demonstrated that neutrinos oscillate and, therefore, that neutrinos have mass. This is a clear crack in the impressive façade of the Standard Model of particle physics and may well lead to a better and more complete theory.

    The neutrino story didn’t end there, though. To understand the phenomenon in greater detail, physicists are now generating beams of neutrinos at many sites over the world, including Fermilab, Brookhaven, CERN and the KEK laboratory in Japan. Combined with studies of neutrinos emitted by nuclear reactors, significant progress has been made in understanding the nature of neutrino oscillation.

    Real mysteries remain. Our measurements have shown that the mass of each neutrino species is different. That’s why we know that some must have mass: if they are different, they can’t all be zero. However, we don’t know the absolute mass of the neutrino species—just the mass differences. We don’t even know which species is the heaviest and which is the lightest.

    The biggest question in neutrino oscillation physics, though, is whether neutrinos and antimatter neutrinos oscillate the same way. If they don’t, this could explain why our universe is composed solely of matter even while we believe that matter and antimatter existed in equal quantities right after the Big Bang.

    Accordingly, Fermilab, America’s premier particle physics laboratory, has launched a multi-decade effort to build the world’s most intense beam of neutrinos, aimed at a distant detector located 800 miles away in South Dakota.

    Sanford Underground Research Facility Interior
    Sanford Underground Research Facility

    Named the Deep Underground Neutrino Experiment (DUNE), it will dominate the neutrino frontier for the foreseeable future.
    FNAL Dune & LBNF

    This year’s Nobel Prize acknowledged a great step forward in our understanding of these ghostly, subatomic chameleons, but their entire story hasn’t been told. The next few decades will be a very interesting time.

    See the full article here .

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    NOVA is the highest rated science series on television and the most watched documentary series on public television. It is also one of television’s most acclaimed series, having won every major television award, most of them many times over.

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