Showing posts with label Neutrinos. Show all posts
Showing posts with label Neutrinos. Show all posts

Saturday, August 24, 2013

How to Make a Neutrino Beam

Hey why not get an animated view of the reasons how? It is from an Symmetry Magazine article on November of 2012. It is information worth remembering in the scheme of particle reductionism..




Neutrinos are elusive particles that are difficult to study, yet they may help explain some of the biggest mysteries of our universe. Using accelerators to make neutrino beams, scientists are unveiling the neutrinos’ secrets. See: How to make a neutrino beam



You might be interested in what they have been doing while us lay people have been pondering what this particle reductionism is all about.  I mean sure there must be benefits from the work that goes on right?



DEMONSTRATION OF COMMUNICATION USING NEUTRINOS




 See Also:

Saturday, April 21, 2012

A Blue Flash in Ice

Little is known about the ultra high-energy cosmic rays that regularly penetrate the atmosphere. Recent IceCube research rules out the leading theory that they come from gamma ray bursts. (Credit: NSF/J. Yang)

Future directions 

The lack of observation of neutrinos in coincidence with GRBs implies, at face value, that the theoretical models need to be revisited. “Calculations embracing the concept that cosmic ray protons are the decay products of neutrons that escaped the magnetic confinement of the GRB fireball are supported by the research community and have been convincingly excluded by the present data,” says Francis Halzen, IceCube principle investigator and a professor of physics at the University of Wisconsin-Madison. "IceCube will continue to collect more data with a final, better calibrated and better understood detector in the coming years." Since April 2011, IceCube has collected neutrino data using the full detector array. With the larger detector, researchers can see more neutrinos, providing a “higher resolution” picture of the neutrino sky. See: Cosmic Rays: 100 years of mystery

See Also: IceCube Neutrino Observatory Explores Origin of Cosmic Rays




IceCube’s 5,160 digital optical modules are suspended from 86 strings reaching a mile and a half below the surface at the South Pole. Each sphere contains a photomultiplier tube and electronics to capture the faint flashes of muons speeding through the ice, their direction and energy – and thus that of the neutrinos that created them – tracked by multiple detections. At lower left is the processed signal of an energetic muon moving upward through the array, created by a neutrino that traveled all the way through the Earth.


“This result represents a coming-of-age of neutrino astronomy,” says Nathan Whitehorn from the University of Wisconsin-Madison, who led the recent GRB research with Peter Redl of the University of Maryland. “IceCube, while still under construction, was able to rule out 15 years of predictions and has begun to challenge one of only two major possibilities for the origin of the highest-energy cosmic rays, namely gamma-ray bursts and active galactic nuclei.”


Redl says, “While not finding a neutrino signal originating from GRBs was disappointing, this is the first neutrino astronomy result that is able to strongly constrain extra-galactic astrophysics models, and therefore marks the beginning of an exciting new era of neutrino astronomy.” The IceCube Collaboration’s report on the search appears in the April 19, 2012, issue of the journal Nature. See: Where Do the Highest-Energy Cosmic Rays Come From? Probably Not from Gamma-Ray Bursts

Thursday, April 19, 2012

A Message from the Past?

The ATLAS Experiment offers the exciting possibility to study them in the lab (if they exist). The simulated collision event shown is viewed along the beampipe. The event is one in which a microscopic-black-hole was produced in the collision of two protons (not shown). The microscopic-black-hole decayed immediately into many particles. The colors of the tracks show different types of particles emerging from the collision (at the center).
Photo #: black-hole-event-wide


I was looking for something in the cosmos that would reveal what is also being revealed in the LHC. We are looking at "interaction points" that are a determinate for the collision point while information which has come from what existed "before" and is being expressed today?



 If such "a point on a line" recognizes that the lines extends "before" the universes birth then where did this information come from? Is it really a void?

Brookhaven National Laboratory
HOT A computer rendition of 4-trillion-degree Celsius quark-gluon plasma created in a demonstration of what scientists suspect shaped cosmic history.

If super fluids can exist in nature then in what circumstances can such information be transferred through that interaction point? Cosmologically this looks real while such comparative natures would say how could such microscopic conditions allow for cosmic particle decays? Chernenko in the ice transmitted through to these detectors as information containing the subject of the particle which collided and came from the cosmos and helped with the new creation of particle determinants?


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Thursday, March 15, 2012

Message Sent Through Rock Via Neutrino Beam

See:Cern Courier:The right spin for a neutrino superfluid

If like myself you are watching the history of communication,  it becomes important to understand the advances we have on the horizon for when we are looking across the expanse of space for consideration of that information transference.


MINERvA: Bringing Neutrinos into Sharp Focus

 
Like radio waves, neutrino beams spread out. Moving farther away from the neutrino source is somewhat like driving away from a radio tower: Eventually you lose the signal. Until physicists create more intense beams of neutrinos or build more powerful detectors, the goal of using neutrinos to communicate with people under the sea or outside Earth’s orbit will remain out of reach.See:Scientists send encoded message through rock via neutrino beam
  While relativistic interpretations are understood with Muon detection scenarios we are able to understand some things about the earth that we had not known before. So in this case we see where such communications are already defining for us some information about the world we live in.


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 Update:

DEMONSTRATION OF COMMUNICATION USING NEUTRINOS
 Beams of neutrinos have been proposed as a vehicle for communications under unusual circumstances, such as direct point-to-point global communication, communication with submarines, secure communications and interstellar communication. We report on the performance of a low-rate communications link established using the NuMI beam line and the MINERvA detector at Fermilab. The link achieved a decoded data rate of 0.1 bits/sec with a bit error rate of 1% over a distance of 1.035 km, including 240 m of earth.


ICARUS: the neutrino speed discrepancy is 0, not 60 ns

 ***
 We examine the possibility to employ neutrinos to communicate within the galaxy. We discuss various issues associated with transmission and reception, and suggest that the resonant neutrino energy near 6.3 PeV may be most appropriate. In one scheme we propose to make Z^o particles in an overtaking e^+ - e^- collider such that the resulting decay neutrinos are near the W^- resonance on electrons in the laboratory. Information is encoded via time structure of the beam. In another scheme we propose to use a 30 PeV pion accelerator to create neutrino or anti-neutrino beams. The latter encodes information via the particle/anti-particle content of the beam, as well as timing. Moreover, the latter beam requires far less power, and can be accomplished with presently foreseeable technology. Such signals from an advanced civilization, should they exist, will be eminently detectable in neutrino detectors now under construction. See:Galactic Neutrino Communication by John G. Learned, Sandip Pakvasa, A. Zee

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Friday, March 09, 2012

Daya Bay

The Daya Bay site in southern China. Image: Lawrence Berkeley Laboratory

An international collaboration of physicists working on a neutrino experiment in southern China announced today they have made a difficult measurement scientists have been chasing for more than a decade.

The results of the Daya Bay neutrino experiment open an important window into understanding the behavior of neutrinos, and now the race is on to determine the implications. Two American experiments, one proposed and one under construction, seem well positioned to take the next steps.
See:Daya Bay experiment makes key measurement, paves way for future discoveries

***
PMTs convert light from particle collisions to electric charge. Since the experiment must collect the light emitted from each event, the reflectors at top and bottom of the acrylic vessels enhance gathering of light.
See:The Daya Bay Neutrino Experiment: On Track to Completion

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  • Dialogos of Eide: Mysterious Behavior of Neutrinos sent Straight



  • Dec 24, 2009... to the NOvA detector in Minnesota. The neutrinos travel the 500 miles in less than three milliseconds. See:NOvA Neutrino Project. ***. Using the NuMI beam to search for electron neutrino appearance. The NOνA Experiment...


  • Dialogos of Eide: Gran Sasso and Fermilab


  • Oct 31, 2011 Funded by a grant from the University of Minnesota. (Credit: Fermilab Visual Media Services). ***. Fermilab experiment weighs in on neutrino mystery. Scientists of the MINOS experiment at the Department of Energy's Fermi...


  • Dialogos of Eide: Linking Experiments



  • Mar 29, 2010 Scientists would use the LBNE to explore whether neutrinos break one of the most fundamental laws of physics: the symmetry between matter and antimatter. In 1980, James Cronin and Val Fitch received the Nobel Prize for...


  • Dialogos of Eide: ICECUBE Blogging Research Material and more


  • Oct 27, 2011 Linking Experiments(Majorana, EXO); How do stars create the heavy elements? (DIANA); What role did neutrinos play in the evolution of the universe? (LBNE). In addition, scientists propose to build a generic underground...

    Thursday, October 27, 2011

    XKCD Significant-Speed of Light Issue?

    You got to love it when correlations can be made, and a thank you to the ICECUBE Blog
    If the histograms and data are exactly right, the paper quotes a one-in-ten-thousand (0.0001) chance that this bump is a fluke. That's pretty small; although bear in mind that lots of distributions like this get plotted. If you plot 100 different distributions, the chances become about one in a hundred (0.01) that you'll see something odd in one of them. The Tevatron goes bump

    http://imgs.xkcd.com/comics/significant.png

    Tuesday, October 18, 2011

    Aspera

    Home Site Located in Title


    A European Network For Astroparticle Physics in Europe

    ASPERA is a network of national government agencies responsible for coordinating and funding national research efforts in Astroparticle Physics



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    See Also: LAGUNA large neutrino observatory design moves forward

    Wednesday, October 05, 2011

    Proton Collision ->Decay to Muons and Muon Neutrinos ->Tau Neutrino ->

    .....tau lepton may travel some tens of microns before decaying back into neutrino and charged tracks




     Before I comment on the result, let me give you a little background on the whole thing. Opera is a very innovative concept in neutrino detection. Its aim is to detect tau neutrino appearance in a beam of muon neutrinos. A Six-Sigma Signal Of Superluminal Neutrinos From Opera!

    The OPERA result is based on the observation of over 15000 neutrino events measured at Gran Sasso, and appears to indicate that the neutrinos travel at a velocity 20 parts per million above the speed of light, nature’s cosmic speed limit. Given the potential far-reaching consequences of such a result, independent measurements are needed before the effect can either be refuted or firmly established. This is why the OPERA collaboration has decided to open the result to broader scrutiny. The collaboration’s result is available on the preprint server arxiv.orghttp://arxiv.org/abs/1109.4897.

    In order to perform this study, the OPERA Collaboration teamed up with experts in metrology from CERN and other institutions to perform a series of high precision measurements of the distance between the source and the detector, and of the neutrinos’ time of flight. The distance between the origin of the neutrino beam and OPERA was measured with an uncertainty of 20 cm over the 730 km travel path. The neutrinos’ time of flight was determined with an accuracy of less than 10 nanoseconds by using sophisticated instruments including advanced GPS systems and atomic clocks. The time response of all elements of the CNGS beam line and of the OPERA detector has also been measured with great precision.

    ***

    By classifying the neutrino interactions according to the type of neutrino involved (electron-neutrino or muon-neutrino) and counting their relative numbers as a function of the distance from their creation point, we conclude that the muon-neutrinos are "oscillating." See: STATEMENT: EVIDENCE FOR MASSIVE NEUTRINOS FOUND by Dave Casper

     ***
    We present an analysis of atmospheric neutrino data from a 33.0 kiloton-year (535-day)exposure of the Super-Kamiokande detector. The data exhibit a zenith angle dependent de ficit of muon neutrinos which is inconsistent with expectations based on calculations of the atmospheric neutrino flux. Experimental biases and uncertainties in the prediction of neutrino fluxes and cross sections are unable to explain our observation. . Evidence for oscillation of atmospheric neutrinos



    See:

    Tuesday, October 04, 2011

    Cherenkov radiation


    Taking the formalisms of electromagnetic radiation and supposing a tachyon had an electric charge—as there is no reason to suppose a priori that tachyons must be either neutral or charged—then a charged tachyon must lose energy as Cherenkov radiation[15]—just as ordinary charged particles do when they exceed the local speed of light in a medium. A charged tachyon traveling in a vacuum therefore undergoes a constant proper time acceleration and, by necessity, its worldline forms a hyperbola in space-time. However, as we have seen, reducing a tachyon's energy increases its speed, so that the single hyperbola formed is of two oppositely charged tachyons with opposite momenta (same magnitude, opposite sign) which annihilate each other when they simultaneously reach infinite speed at the same place in space. (At infinite speed the two tachyons have no energy each and finite momentum of opposite direction, so no conservation laws are violated in their mutual annihilation. The time of annihilation is frame dependent.) Even an electrically neutral tachyon would be expected to lose energy via gravitational Cherenkov radiation, because it has a gravitational mass, and therefore increase in speed as it travels, as described above. See: Tachyon
     ***
    An early set of experiments with a facility called the solar neutrino telescope, measured the rate of neutrino emission from the sun at only one third of the expected flux. Often referred to as the Solar Neutrino Problem, this deficiency of neutrinos has been difficult to explain. Recent results from the Sudbury Neutrino Observatory suggest that a fraction of the electron neutrinos produced by the sun are transformed into muon neutrinos on the way to the earth. The observations at Sudbury are consistent with the solar models of neutrino flux assuming that this "neutrino oscillation" is responsible for observation of neutrinos other than electron neutrinos. See: Detection of Neutrinos

    P.I. Chats: Faster-than-light neutrinos?

    Measurements by GPS confirm that the neutrinos identified by the Super-Kamiokande detector were indeed produced on the east coast of Japan. The physicists therefore estimate that the results obtained point to a 99.3% probability that electron neutrino appearance was detected.Neutrino Oscillations Caught in the Act



    The Gran Sasso National Laboratory (LNGS) is one of four INFN national laboratories.




    PERIMETER INSTITUTE RECORDED SEMINAR ARCHIVE



    PIRSA:11090135  ( Flash Presentation , MP3 , PDF ) Which Format?
    P.I. Chats: Faster-than-light neutrinos?
    Abstract: Can neutrinos really travel faster than light? Recently released experimental data from CERN suggests that they can. Join host Dr. Richard Epp and a panel of Perimeter Institute scientists in a live webinar to discuss this unexpected and puzzling experimental result, and some theoretical questions it might raise.
    Date: 28/09/2011 - 12:15 pm
    Thanks Phil 

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    Using the NuMI beam to search for electron neutrino appearance.

    The NOνA Experiment (Fermilab E929) will construct a detector optimized for electron neutrino detection in the existing NuMI neutrino beam. The primary goal of the experiment is to search for evidence of muon to electron neutrino oscillations. This oscillation, if it occurs, holds the key to many of the unanswered questions in neutrino oscillation physics. In addition to providing a measurement of the last unknown mixing angle, θ13, this oscillation channel opens the possibility of seeing matter/anti-matter asymmetries in neutrinos and determination of the ordering of the neutrino mass states.See:The NOνA Experiment at Fermilab (E929)

    ***

    Image from a neutrino detection experiment. (Credit: Image courtesy of Southern Methodist University)

    Hunting Oscillation of Muon to Electron: Neutrino Data to Flow in 2010; NOvA Scientists Tune Design


    Bee:And for all I know you need a charge for Cherenkov radiation and neutrinos don't have one.

    Thursday, September 29, 2011

    Cassiopeia A

    In conclusion, we have a rich panorama of experiments that all make use of neutrinos as probes of exotic phenomena as well as processes which we have to measure better to gain understanding of fundamental physics as well as gather information about the universe. See:Vernon Barger: perspectives on neutrino physics May 22, 2008


    This image presents a beautiful composite of X-rays from Chandra (red, green, and blue) and optical data from Hubble (gold) of Cassiopeia A, the remains of a massive star that exploded in a supernova. Evidence for a bizarre state of matter has been found in the dense core of the star left behind, a so-called neutron star, based on cooling observed over a decade of Chandra observations. The artist's illustration in the inset shows a cut-out of the interior of the neutron star where densities increase from the crust (orange) to the core (red) and finally to the region where the "superfluid" exists (inner red ball). X-ray: NASA/CXC/UNAM/Ioffe/D. Page, P. Shternin et al.; Optical: NASA/STScI; Illustration: NASA/CXC/M. WeissSee Also:Superfluid and superconductor discovered in star's core

    Illustration of Cassiopeia A Neutron Star
    This is an artist's impression of the neutron star at the center of the Cassiopeia A supernova remnant. The different colored layers in the cutout region show the crust (orange), the higher density core (red) and the part of the core where the neutrons are thought to be in a superfluid state (inner red ball). The blue rays emanating from the center of the star represent the copious numbers of neutrinos that are created as the core temperature falls below a critical level and a superfluid is formed.
    (Credit: Illustration: NASA/CXC/M.Weiss)


    X-ray and Optical Images of Cassiopeia A
    Two independent research teams studied the supernova remnant Cassiopeia A, the remains of a massive star, 11,000 light years away that would have appeared to explode about 330 years as observed from Earth. Chandra data are shown in red, green and blue along with optical data from Hubble in gold. The Chandra data revealed a rapid decline in the temperature of the ultra-dense neutron star that remained after the supernova. The data showed that it had cooled by about 4% over a ten-year period, indicating that a superfluid is forming in its core.
    (Credit: X-ray: NASA/CXC/UNAM/Ioffe/D.Page,P.Shternin et al; Optical: NASA/STScI)
    ***

    See: Galactic Neutrino Communications

    Friday, September 23, 2011

    Measurement of the neutrino velocity with the OPERA detector

    New results from OPERA on neutrino propertieslive from Main Amphitheatre.

    “This result comes as a complete surprise,” said OPERA spokesperson, Antonio Ereditato of the University of Bern. “After many months of studies and cross checks we have not found any instrumental effect that could explain the result of the measurement. While OPERA researchers will continue their studies, we are also looking forward to independent measurements to fully assess the nature of this observation.” 


     “When an experiment finds an apparently unbelievable result and can find no artefact of the measurement to account for it, it’s normal procedure to invite broader scrutiny, and this is exactly what the OPERA collaboration is doing, it’s good scientific practice,” said CERN Research Director Sergio Bertolucci. “If this measurement is confirmed, it might change our view of physics, but we need to be sure that there are no other, more mundane, explanations. That will require independent measurements.”See:OPERA experiment reports anomaly in flight time of neutrinos from CERN to Gran Sasso




    Have we considered their mediums of expression to know that we have witnessed Cerenkov radiation as a process in the faster than light, to know the circumstances of such expressions to have been understood as backdrop measures of processes we are familiar with. Explain the history of particulate expressions from vast distances across our universe?

    The OPERA Detector


    This is something very different though and it will be very interesting the dialogue and thoughts shared so as to look at the evidence in a way that helps us to consider what is sound in it's understanding, as speed of light.

    See Also:

    Friday, April 22, 2011

    Geo-neutrinos



    The main geophysical and geochemical processes that have driven the evolution of the Earth are strictly bound by the planet̓s energy budget. The current flux of energy entering the Earth’s atmosphere is well known: the main contribution comes from solar radiation (1.4 × 103 W m–2), while the energy deposited by cosmic rays is significantly smaller (10–8 W m–2). The uncertainties on terrestrial thermal power are larger – although the most quoted models estimate a global heat loss in the range of 40–47 TW, a global power of 30 TW is not excluded. The measurements of the temperature gradient taken from some 4 × 104 drill holes distributed around the world provide a constraint on the Earth’s heat production. Nevertheless, these direct investigations fail near the oceanic ridge, where the mantle content emerges: here hydrothermal circulation is a highly efficient heat-transport mechanism.

    The generation of the Earth’s magnetic field, its mantle circulation, plate tectonics and secular (i.e. long lasting) cooling are processes that depend on terrestrial heat production and distribution, and on the separate contributions to Earth’s energy supply (radiogenic, gravitational, chemical etc.). An unambiguous and observationally based determination of radiogenic heat production is therefore necessary for understanding the Earth’s energetics. Such an observation requires determining the quantity of long-lived radioactive elements in the Earth. However, the direct geochemical investigations only go as far as the upper portion of the mantle, so all of the geochemical estimates of the global abundances of heat-generating elements depend on the assumption that the composition of meteorites reflects that of the Earth.
    See:Looking into the Earth’s interior with geo-neutrinos

    Monday, March 29, 2010

    Linking Experiments

    Illustration: Sandbox Studio

     

    The first round of physics

    Nine proposals are under consideration for the initial suite of physics experiments at DUSEL, and scientists have received $21 million in NSF funding to refine them. The proposals cover four areas of research:
    • What is the nature of dark matter? (Proposals for LZ3, COUPP, GEODM, and MAX)
    • Are neutrinos their own antiparticles? (Majorana, EXO)
    • How do stars create the heavy elements? (DIANA)
    • What role did neutrinos play in the evolution of the universe? (LBNE)
    In addition, scientists propose to build a generic underground facility (FAARM) that will monitor the mine's naturally occurring radioactivity, which can interfere with the search for dark matter. The facility also would measure particle emissions from various materials, and help develop and refine technologies for future underground physics experiments.
    But why are there four separate proposals for how to search for dark matter? Not knowing the nature of dark-matter particles and their interactions with ordinary matter, scientists would like to use a variety of detector materials to look for the particles and study their interactions with atoms of different sizes. The use of different technologies would also provide an independent cross check of the experimental results.
    "We strongly feel we need two or more experiments," says Bernard Sadoulet of UC Berkeley, an expert on dark-matter searches. "If money were not an issue, you would build at least three experiments."
    The largest experiment intended for DUSEL is the Long-Baseline Neutrino Experiment (see graphic), a project that involves both the DOE and NSF. Scientists would use the LBNE to explore whether neutrinos break one of the most fundamental laws of physics: the symmetry between matter and antimatter. In 1980, James Cronin and Val Fitch received the Nobel Prize for the observation that quarks can violate this symmetry. But the effect is too small to explain the dominance of matter over antimatter in our universe. Neutrinos might be the answer.
    The LBNE scientists would generate a high-intensity neutrino beam at DOE's Fermi National Accelerator Laboratory, 800 miles east of Homestake, and aim it straight through the Earth at two or more enormous neutrino detectors in the DUSEL mine, each containing the equivalent of 100,000 tons of water.
    Studies have shown that the rock at the 4850-foot level of the mine would support the safe construction of these caverns. In January, the LBNE experiment received first-stage approval, also known as Mission Need, from the DOE.
    Lesko and his team now are combining all engineering studies and science proposals into an overall proposal for review.
    "By the end of this summer, we hope to complete a preliminary design of the DUSEL facility and then integrate it with a generic suite of experiments," Lesko says. "While formal selection of the experiments will not have been made by that time, we know enough about them now that we can move forward with the preliminary design. The experiments themselves will be selected through a peer-review process, as is common in the NSF."
    If all goes well, Lesko says, scientists and engineers could break ground on the major DUSEL excavations in 2013, marking the start of a new era for deep underground research in the United States. SEE:Big Plans for Deep Science

    See Also: 

    Monday, March 22, 2010

    A first look at the Earth interior from the Gran Sasso underground laboratory

    The Gran Sasso National Laboratory (LNGS) is one of four INFN national laboratories.
    It is the largest underground laboratory in the world for experiments in particle physics, particle astrophysics and nuclear astrophysics. It is used as a worldwide facility by scientists, presently 750 in number, from 22 different countries, working at about 15 experiments in their different phases.

    It is located between the towns of L'Aquila and Teramo, about 120 km from Rome
    .
    The underground facilities are located on a side of the ten kilometres long freeway tunnel crossing the Gran Sasso Mountain. They consist of three large experimental halls, each about 100 m long, 20 m wide and 18 m high and service tunnels, for a total volume of about 180,000 cubic metres.
    ***
    Slide by Takaaki Kajita
    In June 1998 the Super-Kamiokande collaboration revealed its eagerly anticipated results on neutrino interactions to 400 physicists at the Neutrino ’98 conference in Takayama, Japan. A hearty round of applause marked the end of a memorable presentation by Takaaki Kajita of the University of Tokyo that included this slide. He presented strong evidence that neutrinos behave differently than predicted by the Standard Model of particles: The three known types of neutrinos apparently transform into each other, a phenomenon known as oscillation.

    Super-K’s detector, located 1000 meters underground, had collected data on neutrinos produced by a steady stream of cosmic rays hitting the Earth’s atmosphere. The data allowed scientists to distinguish between two types of atmospheric neutrinos: those that produce an electron when interacting with matter (e-like), and those that produce a muon (μ-like). The graph in this slide shows the direction the neutrinos came from (represented by cos theta, on the x-axis); the number of neutrinos observed (points marked with crosses); and the number expected according to the Standard Model (shaded boxes).

    In the case of the μ-like neutrinos, the number coming straight down from the sky into the detector agreed well with theoretical prediction. But the number coming up through the ground was much lower than anticipated. These neutrinos, which originated in the atmosphere on the opposite side of the globe, travelled 13,000 kilometers through the Earth before reaching the detector. The long journey gave a significant fraction of them enough time to “disappear”—shedding their μ-like appearance by oscillating into a different type of neutrino. While earlier experiments had pointed to the possibility of neutrino oscillations, the disappearance of μ-like neutrinos in the Super-K experiment provided solid evidence.
    ***
    Click on this BlogTitled link



    The Borexino Collaboration announced the observation of geo-neutrinos at the underground Gran Sasso National Laboratory of Italian Institute for Nuclear Physics (INFN), Italy. The data reveal, for the first time, a definite anti-neutrino signal with the expected energy spectrum due to radioactive decays of U and Th in the Earth well above background.

    The International Borexino Collaboration, with institutions from Italy, US, Germany, Russia, Poland and France, operates a 300-ton liquid-scintillator detector designed to observe and study low-energy solar neutrinos. The low background of the Borexino detector has been key to the detection of geo-neutrinos. Technologies developed by Borexino Collaborators have achieved very low background levels. The central core of the Borexino scintillator is now the lowest background detector available for these observations. The ultra-low background of Borexino was developed to make the first measurements of solar neutrinos below 1 MeV and has now produced this first, firm observation of geo-neutrinos.

    Geo-neutrinos are anti-neutrinos produced in radioactive decays of naturally occurring Uranium, Thorium, Potassium, and Rubidium. Decays from these radioactive elements are believed to contribute a significant but unknown fraction of the heat generated inside our planet. The heat generates convective movements in the Earth's mantle that influence volcanic activity and tectonic plate movements inducing seismic activity, and the geo-dynamo that creates the Earth's magnetic field.
    More above......

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    Links borrowed from here

    Browsing experiments
     • auger (7 photos)
     • borexino (6 photos)
     • cobra (6 photos)
     • cresst (5 photos)
     • cryostem (2 photos)
     • cuore (5 photos)
     • cuoricino (3 photos)
     • dama (9 photos)
     • eastop (4 photos)
     • ermes (2 photos)
     • genius (3 photos)
     • gerda (1 photos)
     • gigs (3 photos)
     • gno (6 photos)
     • hdms (2 photos)
     • hmbb (1 photos)
     • icarus (19 photos)
     • lisa (1 photos)
     • luna (5 photos)
     • lvd (4 photos)
     • macro (4 photos)
     • mibeta (1 photos)
     • opera (26 photos)
     • tellus (1 photos)
     • underseis (8 photos)
     • vip (1 photos)
     • warp (10 photos)
     • xenon (4 photos)
     • zoo (3 photos)


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    See Also:

    Friday, March 19, 2010

    Neutrinoless Double Beta Decay

    You don’t see what you’re seeing until you see it,” Dr. Thurston said, “but when you do see it, it lets you see many other things.Elusive Proof, Elusive Prover: A New Mathematical Mystery


    The Enriched Xenon Observatory is an experiment in particle physics aiming to detect "neutrino-less double beta decay" using large amounts of xenon isotopically enriched in the isotope 136. A 200-kg detector using liquid Xe is currently being installed at the Waste Isolation Pilot Plant (WIPP) near Carlsbad, New Mexico. Many research and development efforts are underway for a ton-scale experiment, with the goal of probing new physics and the mass of the neutrino. The Enriched Xenon Observatory

    ***
    Feynman diagram of neutrinoless double-beta decay, with two neutrons decaying to two protons. The only emitted products in this process are two electrons, which can only occur if the neutrino and antineutrino are the same particle (i.e. Majorana neutrinos) so the same neutrino can be emitted and absorbed within the nucleus. In conventional double-beta decay, two antineutrinos - one arising from each W vertex - are emitted from the nucleus, in addition to the two electrons. The detection of neutrinoless double-beta decay is thus a sensitive test of whether neutrinos are Majorana particles.


    Neutrinoless double-beta decay experiments

    Numerous experiments have been carried out to search for neutrinoless double-beta decay. Some recent and proposed future experiments include:

    See:Direct Dark Matter Detection


     See Also: South Dakota's LUX will join the dark matter wars