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Cosmic Closure: Relating the Ultimate Fate of Massive Stars and the Ultimate Fate of the Universe

Description: We give a brief overview of the status of core collapse supernova modeling, particularly as it pertains to predictions of neutrino signatures for the next galactic or near extragalactic supernova. We also consider the implications of neutrino mass for both the supernova mechanism and neutrino signature predictions.
Date: September 7, 1998
Creator: Bruenn, S.W. & Mezzacappa, A.
Partner: UNT Libraries Government Documents Department

A Lower Bound on Neutrino Mass And Its Implication on the Z-Burst Scenario

Description: We show that the cascade limit on ultra high energy cosmic neutrino (UHEC/nu) flux imposes a lower bound on the neutrino mass provided that super-GZK events of ultra high energy cosmic rays (UHECRs) are produced from Z-bursts. Based on the data from HiRes and AGASA, the obtained neutrino mass lower bound violates its existing cosmological upper bound. We conclude that the Z-burst cannot be the dominant source for the observed super-GZK UHECR events. This is consistent with the recent ANITA-lite data.
Date: January 11, 2006
Creator: Lai, Kwang-Chang; /Taiwan, Natl. Taiwan U.; Chen, Pisin & /KIPAC, Menlo Park
Partner: UNT Libraries Government Documents Department

MeV Dark Matter and Small Scale Structure

Description: WIMPs with electroweak scale masses (neutralinos, etc.) remain in kinetic equilibrium with other particle species until temperatures approximately in the range of 10 MeV to 1 GeV, leading to the formation of dark matter substructure with masses as small as 10{sup -4} M{sub {circle_dot}} to 10{sup -12} M{sub {circle_dot}}. However, if dark matter consists of particles with MeV scale masses, as motivated by the observation of 511 keV emission from the Galactic Bulge, such particles are naturally expected to remain in kinetic equilibrium with the cosmic neutrino background until considerably later times. This would lead to a strong suppression of small scale structure with masses below about 10{sup 7}M{sub {circle_dot}} to 10{sup 4} M{sub {circle_dot}}. This cutoff scale has important implications for present and future searches for faint Local Group satellite galaxies and for the missing satellites problem.
Date: April 1, 2007
Creator: Hooper, Dan; /Fermilab; Kaplinghat, Manoj; Strigari, Louis E.; /UC, Irvine; Zurek, Kathryn M. et al.
Partner: UNT Libraries Government Documents Department

A prototype station for ARIANNA: a detector for cosmic neutrinos

Description: The Antarctic Ross Iceshelf Antenna Neutrino Array (ARIANNA) is a proposed detector for ultra-high energy astrophysical neutrinos. It will detect coherent radio Cherenkov emission from the particle showers produced by neutrinos with energies above about 1017 eV. ARIANNA will be built on the Ross Ice Shelf just off the coast of Antarctica, where it will eventually cover about 900 km2 in surface area. There, the ice-water interface below the shelf reflects radio waves, giving ARIANNA sensitivity to downward going neutrinos and improving its sensitivity to horizontally incident neutrinos. ARIANNA detector stations will each contain 4-8 antennas which search for brief pulses of 50 MHz to 1 GHz radio emission from neutrino interactions. We describe a prototype station for ARIANNA which was deployed in Moore's Bay on the Ross Ice Shelf in December 2009, discuss the design and deployment, and present some initial figures on performance. The ice shelf thickness was measured to be 572 +- 6 m at the deployment site.
Date: May 27, 2010
Creator: Gerhardt, L.; Klein, S.; Stezelberger, T.; Barwick, S.; Dookayka, K.; Hanson, J. et al.
Partner: UNT Libraries Government Documents Department

Relic neutrino detector

Description: Probably the most promising way of detecting cosmic neutrinos is measuring the mechanical force exerted by clastic scattering of cosmic neutrinos from macroscopic targets. The expected acceleration is ~10<sup>-23</sup>cm/s<sup>2</sup> for Dirac neutrinos of mass ~10 eV and local density ~10<sup>7</sup>/cm<sup>3</sup>. A novel torsion balance design is presented, which addresses the sensitivity-limiting factors of existing balances, such as seismic and thermal noise, and angular readout resolution and stability.
Date: January 27, 1999
Creator: Hagmann, C.
Partner: UNT Libraries Government Documents Department

The atmospheric neutrino flavor ratio in Soudan 2.

Description: We have measured the flavor ratio of ratios (R) in atmospheric neutrino interactions using a 1.52 kton-year exposure of Soudan 2. We find R = 0.67 {+-} 0.15{sub {minus}0.06}{sup +0.04}. This value is about 2{sigma} from the expected value of 1.0 and is consistent with the anomalous ratios measured by the Kamiokande and IMB experiments. We note that since our acceptance matrix is different from those of the water Cherenkov experiments we would not expect to measure the same value of R, unless R=1.
Date: October 15, 1997
Creator: Goodman, M.
Partner: UNT Libraries Government Documents Department

AMANDA Observations Constrain the Ultrahigh Energy Neutrino Flux

Description: A number of experimental techniques are currently being deployed in an effort to make the first detection of ultra-high energy cosmic neutrinos. To accomplish this goal, techniques using radio and acoustic detectors are being developed, which are optimally designed for studying neutrinos with energies in the PeV-EeV range and above. Data from the AMANDA experiment, in contrast, has been used to place limits on the cosmic neutrino flux at less extreme energies (up to {approx}10 PeV). In this letter, we show that by adopting a different analysis strategy, optimized for much higher energy neutrinos, the same AMANDA data can be used to place a limit competitive with radio techniques at EeV energies. We also discuss the sensitivity of the IceCube experiment, in various stages of deployment, to ultra-high energy neutrinos.
Date: May 1, 2006
Creator: Halzen, Francis; /Wisconsin U., Madison; Hooper, Dan & /Fermilab
Partner: UNT Libraries Government Documents Department

Study of electron and neutrino interactions. Final report

Description: This is the final report for the DOE-sponsored experimental particle physics program at Virginia Tech to study the properties of the Standard Model of strong and electroweak interactions. This contract (DE-AS05-80ER10713) covers the period from August 1, 1980 to January 31, 1993. Task B of this contract, headed by Professor Alexander Abashian, is described in this final report. This program has been pursued on many fronts by the researchers in a search for axions at SLAC, in electron-positron collisions in the AMY experiment at the TRISTAN collider in Japan, in measurements of muon decay properties in the MEGA and RHO experiments at the LAMPF accelerator, in a detailed analysis of scattering effects in the purported observation of a 17 keV neutrino at Oxford, in a search for a disoriented chiral condensate with the MiniMax experiment at Fermilab, and in an R&D program on resistive plate counters that could find use in low-cost high-quality charged particle detection at low rates.
Date: March 18, 1997
Creator: Abashian, A.
Partner: UNT Libraries Government Documents Department

Search for AGN neutrinos with the Soudan 2 detector

Description: Several authors have presented models for neutrino production from Active Galactic Nuclei (AGN) that allow for the possibility of AGN neutrinos outnumbering the atmospheric neutrino flux for energies in excess of 30 TeV. Preliminary results from a search for high energy neutrinos from AGN using the underground Soudan 2 Detector are presented.
Date: May 1, 1997
Creator: DeMuth, D. M.
Partner: UNT Libraries Government Documents Department

Search for AGN neutrinos with the soudan 2 detector.

Description: Several authors have presented models for neutrino production from Active Galactic Nuclei (AGN) that allow for the possibility of AGN neutrinos outnumbering the atmospheric neutrino flux for energies in excess of 30 TeV. The authors present preliminary results from a search for high energy neutrinos from AGN using the underground Soudan 2 Detector.
Date: October 15, 1997
Creator: DeMuth, D. M.
Partner: UNT Libraries Government Documents Department

Ideas for a long-baseline neutrino detector

Description: The Atmospheric Neutrino Deficit defines a region in {Delta}m{sup 2}-sin{sup 2}2{theta} space which ought to be conclusively tested in a long-baseline experiment. This talk sets out a region to cover (which may change as more data is analyzed) and translates that region into an L/E. I present exclusion curves for different experiments based on their distance and their precision; I conclude that an experiment which can detect oscillations down to 1% located at 1200 km will cleanly test the allowed region from Kamioka and IMB. I then describe the techniques which can perform such a measurement and outline both a detector capable of performing such an experiment and some of the systematic problems we might expect.
Date: February 1, 1992
Creator: Bernstein, R.
Partner: UNT Libraries Government Documents Department

New Limits on the Ultra-High Energy Cosmic Neutrino Flux from the ANITA Experiment

Description: We report initial results of the first flight of the Antarctic Impulsive Transient Antenna (ANITA-1) 2006-2007 Long Duration Balloon flight, which searched for evidence of a diffuse flux of cosmic neutrinos above energies of E{sub v} = 3 x 10{sup 18} eV. ANITA-1 flew for 35 days looking for radio impulses due to the Askaryan effect in neutrino-induced electromagnetic showers within the Antarctic ice sheets. We report here on our initial analysis, which was performed as a blind search of the data. No neutrino candidates are seen, with no detected physics background. We set model-independent limits based on this result. Upper limits derived from our analysis rule out the highest cosmogenic neutrino models. In a background horizontal-polarization channel, we also detect six events consistent with radio impulses from ultrahigh energy extensive air showers.
Date: December 1, 2011
Creator: Gorham, P.W.; Allison, P.; U., /Hawaii; Barwick, S.W.; /UC, Irvine; Beatty, J.J. et al.
Partner: UNT Libraries Government Documents Department

Cosmic Neutrinos

Description: I recall the place of neutrinos in the electroweak theory and summarize what we know about neutrino mass and flavor change. I next review the essential characteristics expected for relic neutrinos and survey what we can say about the neutrino contribution to the dark matter of the Universe. Then I discuss the standard-model interactions of ultrahigh-energy neutrinos, paying attention to the consequences of neutrino oscillations, and illustrate a few topics of interest to neutrino observatories. I conclude with short comments on the remote possibility of detecting relic neutrinos through annihilations of ultrahigh-energy neutrinos at the Z resonance.
Date: February 1, 2008
Creator: Quigg, Chris
Partner: UNT Libraries Government Documents Department

Extremely high energy cosmic neutrinos and relic neutrinos

Description: I review the essentials of ultrahigh-energy neutrino interactions, show how neutral-current detection and flavor tagging can enhance the scientific potential of neutrino telescopes, and sketch new studies on neutrino encounters with dark matter relics and on gravitational lensing of neutrinos.
Date: March 1, 2006
Creator: Quigg, Chris
Partner: UNT Libraries Government Documents Department

Cosmological neutrino mass detection: The Best probe of neutrino lifetime

Description: Future cosmological data may be sensitive to the effects of a finite sum of neutrino masses even as small as {approx}0.06 eV, the lower limit guaranteed by neutrino oscillation experiments. We show that a cosmological detection of neutrino mass at that level would improve by many orders of magnitude the existing limits on neutrino lifetime, and as a consequence on neutrino secret interactions with (quasi-)massless particles as in majoron models. On the other hand, neutrino decay may provide a way-out to explain a discrepancy {approx}&lt; 0.1 eV between cosmic neutrino bounds and Lab data.
Date: January 1, 2007
Creator: Serpico, Pasquale D.
Partner: UNT Libraries Government Documents Department

Probing exotic physics with cosmic neutrinos

Description: Traditionally, collider experiments have been the primary tool used in searching for particle physics beyond the Standard Model. In this talk, I will discuss alternative approaches for exploring exotic physics scenarios using high energy and ultra-high energy cosmic neutrinos. Such neutrinos can be used to study interactions at energies higher, and over baselines longer, than those accessible to colliders. In this way, neutrino astronomy can provide a window into fundamental physics which is highly complementary to collider techniques. I will discuss the role of neutrino astronomy in fundamental physics, considering the use of such techniques in studying several specific scenarios including low scale gravity models, Standard Model electroweak instanton induced interactions, decaying neutrinos and quantum decoherence.
Date: October 1, 2005
Creator: Hooper, Dan
Partner: UNT Libraries Government Documents Department

Neutrino clouds and dark matter

Description: We have examined the consequences of assuming the existence of a light scalar boson, weakly coupled to neutrinos, and not coupled to any other light fermions. For a range of parameters, we find that this hypothesis leads to the development of neutrino clusters which form in the early Universe and which provide gravitational fluctuations on scales small compared to a parsec (i.e., the scale of solar systems). Under some conditions, this can produce anomalous gravitational acceleration within solar systems and lead to a vanishing of neutrino mass-squared differences, giving rise to strong neutrino oscillation effects.
Date: December 31, 1996
Creator: Goldman, T.; McKellar, B.H.J. & Stephenson, G.J. Jr.
Partner: UNT Libraries Government Documents Department

Long-Baseline Neutrino Oscillation Experiments

Description: There is no unambiguous definition for long baseline neutrino oscillation experiments. The term is generally used for accelerator neutrino oscillation experiments which are sensitive to {Delta}m{sup 2} < 1.0 eV{sup 2}, and for which the detector is not on the accelerator site. The Snowmass N2L working group met to discuss the issues facing such experiments. The Fermilab Program Advisory Committee adopted several recommendations concerning the Fermilab neutrino program at their Aspen meeting immediately prior to the Snowmass Workshop. This heightened the attention for the proposals to use Fermilab for a long-baseline neutrino experiment at the workshop. The plan for a neutrino oscillation program at Brookhaven was also thoroughly discussed. Opportunities at CERN were considered, particularly the use of detectors at the Gran Sasso laboratory. The idea to build a neutrino beam from KEK towards Superkamiokande was not discussed at the Snowmass meeting, but there has been considerable development of this idea since then. Brookhaven and KEK would use low energy neutrino beams, while FNAL and CERN would plan have medium energy beams. This report will summarize a few topics common to LBL proposals and attempt to give a snapshot of where things stand in this fast developing field.
Date: December 31, 1994
Creator: Crane, Dan & Goodman, Maury
Partner: UNT Libraries Government Documents Department

Interactions of atmospheric {nu}{sub {mu}} and {nu}{sub e} observed in Soudan 2

Description: We present preliminary measurements of the relative rates of atmospheric {nu}{sub {mu}} and {nu}{sub e} interactions from the first 0.5 kton-year exposure of the Soudan 2 experiment. The results are consistent with deficit of {nu}{sub {mu}} relative to {nu}{sub e} reported by the water Cerenkov experiments, which may be evidence for neutrino oscillations.
Date: December 31, 1992
Creator: Goodman, Maury
Partner: UNT Libraries Government Documents Department

DUMAND-II progress report

Description: The design, scientific goals, and capabilities of the DUMAND II detector system are described. Construction was authorized by DOE in 1990, and development of various detector subsystems is under way. Current plans include deployment of the shore cable, junction box and three strings of optical detector modules in 1992, with expansion to the full 9-string configuration about one year later.
Date: December 31, 1991
Creator: Wilkes, R. J. & Collaboration, DUMAND
Partner: UNT Libraries Government Documents Department

Search for AGN {nu}`s with the Soudan 2 detector

Description: We present a preliminary null result from a search for diffuse high energy neutrino emission by Active Galactic Nuclei. The method relies on the measurement of catastrophic energy loss by high energy muons in the Soudan 2 calorimeter. A Monte Carlo calculation of the energy loss of high energy muons is described.
Date: August 1, 1992
Creator: Ambats, I.; Ayres, D. S.; Balka, L. J.; Barrett, W. L.; Brock, T.; Dawson, J. W. et al.
Partner: UNT Libraries Government Documents Department

Accelerator-based neutrino oscillation searches

Description: This paper attempts to summarize the neutrino oscillation section of the Workshop on Future Directions in Particle and Nuclear Physics at Multi-GeV Hadron Beam Facilities. There were very lively discussions about the merits of the different oscillation channels, experiments, and facilities, but we believe a substantial consensus emerged. First, the next decade is one of great potential for discovery in neutrino physics, but it is also one of great peril. The possibility that neutrino oscillations explain the solar neutrino and atmospheric neutrino experiments, and the indirect evidence that Hot Dark Matter (HDM) in the form of light neutrinos might make up 30% of the mass of the universe, point to areas where accelerator-based experiments could play a crucial role in piecing together the puzzle. At the same time, the field faces a very uncertain future. The LSND experiment at LAMPF is the only funded neutrino oscillation experiment in the United States and it is threatened by the abrupt shutdown of LAMPF proposed for fiscal 1994. The future of neutrino physics at the Brookhaven National Laboratory AGS depends the continuation of High Energy Physics (HEP) funding after the RHIC startup. Most proposed neutrino oscillation searches at Fermilab depend on the completion of the Main Injector project and on the construction of a new neutrino beamline, which is uncertain at this point. The proposed KAON facility at TRIUMF would provide a neutrino beam similar to that at the AGS but with a much increase intensity. The future of KAON is also uncertain. Despite the difficult obstacles present, there is a real possibility that we are on the verge of understanding the masses and mixings of the neutrinos. The physics importance of such a discovery can not be overstated. The current experimental status and future possibilities are discussed below.
Date: October 1, 1993
Creator: Whitehouse, D. A.; Rameika, R. & Stanton, N.
Partner: UNT Libraries Government Documents Department

Probing low-x QCD with cosmic neutrinos at the Pierre Auger Observatory

Description: The sources of the observed ultra-high energy cosmic rays must also generate ultra-high energy neutrinos. Deep inelastic scattering of these neutrinos with nucleons on Earth probe center-of-mass energies {radical}s {approx} 100 TeV, well beyond those attainable at terrestrial colliders. By comparing the rates for two classes of observable events, any departure from the benchmark (unscreened perturbative QCD) neutrino-nucleon cross-section can be constrained. Using the projected sensitivity of the Pierre Auger Observatory to quasi-horizontal showers and Earth-skimming tau neutrinos, we show that a ''Super-Auger'' detector can thus provide an unique probe of strong interaction dynamics.
Date: May 1, 2006
Creator: Anchordoqui, Luis A.; /Northeastern U. /Wisconsin U., Milwaukee; Cooper-Sarkar, Amanda M.; U., /Oxford; Hooper, Dan; /Fermilab et al.
Partner: UNT Libraries Government Documents Department

Neutrino radiation hazards: A paper tiger

Description: Neutrinos are present in the natural environment due to terrestrial, solar, and cosmic sources and are also produced at accelerators both incidentally and intentionally as part of physics research programs. Progress in fundamental physics research has led to the creation of beams of neutrinos of ever-increasing intensity and/or energy. The large size and cost associated with these beams attracts, and indeed requires, public interest, support, and some understanding of the `exotic` particles produced, including the neutrinos. Furthermore, the very word neutrino (`little neutral one`, as coined by Enrico Fermi) can lead to public concern due to confusion with `neutron`, a word widely associated with radiological hazards. Adding to such possible concerns is a recent assertion, widely publicized, that neutrinos from astronomical events may have led to the extinction of some biological species. Presented here are methods for conservatively estimating the dose equivalent due to neutrinos as well as an assessment of the possible role of neutrinos in biological extinction processes. It is found that neutrinos produced by the sun and modern particle accelerators produce inconsequential dose equivalent rates. Examining recent calculations concerning neutrinos incident upon the earth due to stellar collapse, it is concluded that it is highly unlikely that these neutrinos caused the mass extinctions of species found in the paleontological record. Neutrino radiation hazards are, then, truly a `paper tiger`. 14 refs., 1 fig., 1 tab.
Date: September 1, 1996
Creator: Cossairt, J.D.; Grossman, N.L. & Marshall, E.T.
Partner: UNT Libraries Government Documents Department