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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

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

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

Current trends in non-accelerator particle physics: 1, Neutrino mass and oscillation. 2, High energy neutrino astrophysics. 3, Detection of dark matter. 4, Search for strange quark matter. 5, Magnetic monopole searches

Description: This report is a compilation of papers reflecting current trends in non-accelerator particle physics, corresponding to talks that its author was invited to present at the Workshop on Tibet Cosmic Ray Experiment and Related Physics Topics held in Beijing, China, April 4--13, 1995. The papers are entitled `Neutrino Mass and Oscillation`, `High Energy Neutrino Astrophysics`, `Detection of Dark Matter`, `Search for Strange Quark Matter`, and `Magnetic Monopole Searches`. The report is introduced by a survey of the field and a brief description of each of the author`s papers.
Date: July 1, 1995
Creator: He, Yudong
Partner: UNT Libraries Government Documents Department

The large scale microwave background anisotropy in decaying particle cosmology

Description: We investigate the large-scale anisotropy of the microwave background radiation in cosmological models with decaying particles. The observed value of the quadrupole moment combined with other constraints gives an upper limit on the redshift of the decay z/sub d/ < 3-5. 12 refs., 2 figs.
Date: June 1, 1987
Creator: Panek, M.
Partner: UNT Libraries Government Documents Department

Indirect detection of heavy supersymmetric dark matter

Description: If neutralinos reside in the galactic halo they will be captured in the Sun and annihilate therein producing high-energy neutrinos. Present limits on the flux of such neutrinos from underground detectors such as IMB and Kamiokande 2 may be used to rule out certain supersymmetric dark-matter candidates, while in many other supersymmetric models the rates are large enough that if neutralinos do reside in the galactic halo, observation of a neutrino signal may be possible in the near future. 10 refs., 2 figs.
Date: February 1, 1991
Creator: Kamionkowski, M. (Chicago Univ., IL (USA))/(Fermi National Accelerator Lab., Batavia, IL (USA))
Partner: UNT Libraries Government Documents Department

Muon/electron separation for atmospheric neutrino interactions

Description: A study has been made of the ability of the Soudan 2 nucleon decay detector to distinguish between showering and non-showering particles, utilizing several different pattern recognition techniques. This work has direct application in the determination of the {nu}{sub {mu}}/{nu}{sub e} ratio for atmospheric neutrino induced events. The results of the application of these techniques to Monte Carlo data and to calibration data from the ISIS test beam are presented.
Date: August 1, 1991
Creator: Allison, W.W.M.; Barr, G.D.; Brooks, C.B.; Cobb, J.H.; Kirby-Gallagher, L.M.; Giles, R.H. et al.
Partner: UNT Libraries Government Documents Department

Search for neutrino oscillations at BNL preliminary results from E 816 experiment

Description: Neutrino interactions in a fine-grain calorimeter have been analyzed with emphasis on events with associated electromagnetic showers. The good granularity of the detector allows to separate photon from electron showers. The number of events with an electron, according to the present status of our analysis, is found to be about three times larger than expected on the basis of the beam composition. 9 refs., 7 figs.
Date: March 1, 1987
Creator: Bernardi, G.
Partner: UNT Libraries Government Documents Department

A measurement of the hadronic component of air showers in a fine grained calorimeter

Description: The hadronic component of extensive air showers is studied using the E594 fine grained calorimeter and a air shower array trigger. Hadron angle and energy distributions are shown. Events with more than one separated hadron with substantial energy are studied carefully. The correlation of hadronic and muonic components is shown. 2 refs., 3 figs.
Date: January 1, 1987
Creator: Goodman, M.C.; Ellsworth, G.B.; Bofill, J.; Bogert, D.; Freudenreich, H.; Goodman, J.A. et al.
Partner: UNT Libraries Government Documents Department