skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: AMANDA Observations Constrain the Ultrahigh Energy Neutrino Flux

Abstract

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.

Authors:
; ; ;
Publication Date:
Research Org.:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
892504
Report Number(s):
FERMILAB-PUB-06-097-A
arXiv eprint number astro-ph/0605103; TRN: US0701483
DOE Contract Number:
AC02-76CH03000
Resource Type:
Journal Article
Resource Relation:
Journal Name: Phys.Rev.Lett.97:099901,2006
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ACOUSTICS; COSMIC NEUTRINOS; DETECTION; NEUTRINOS; SENSITIVITY; Astrophysics

Citation Formats

Halzen, Francis, /Wisconsin U., Madison, Hooper, Dan, and /Fermilab. AMANDA Observations Constrain the Ultrahigh Energy Neutrino Flux. United States: N. p., 2006. Web. doi:10.1103/PhysRevLett.97.071101.
Halzen, Francis, /Wisconsin U., Madison, Hooper, Dan, & /Fermilab. AMANDA Observations Constrain the Ultrahigh Energy Neutrino Flux. United States. doi:10.1103/PhysRevLett.97.071101.
Halzen, Francis, /Wisconsin U., Madison, Hooper, Dan, and /Fermilab. Mon . "AMANDA Observations Constrain the Ultrahigh Energy Neutrino Flux". United States. doi:10.1103/PhysRevLett.97.071101. https://www.osti.gov/servlets/purl/892504.
@article{osti_892504,
title = {AMANDA Observations Constrain the Ultrahigh Energy Neutrino Flux},
author = {Halzen, Francis and /Wisconsin U., Madison and Hooper, Dan and /Fermilab},
abstractNote = {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.},
doi = {10.1103/PhysRevLett.97.071101},
journal = {Phys.Rev.Lett.97:099901,2006},
number = ,
volume = ,
place = {United States},
year = {Mon May 01 00:00:00 EDT 2006},
month = {Mon May 01 00:00:00 EDT 2006}
}
  • The AMANDA-II detector, operating since 2000 in the deep ice at the geographic South Pole, has accumulated a large sample of atmospheric muon neutrinos in the 100 GeV to 10 TeV energy range. The zenith angle and energy distribution of these events can be used to search for various phenomenological signatures of quantum gravity in the neutrino sector, such as violation of Lorentz invariance (VLI) or quantum decoherence (QD). Analyzing a set of 5511 candidate neutrino events collected during 1387 days of livetime from 2000 to 2006, we find no evidence for such effects and set upper limits on VLImore » and QD parameters using a maximum likelihood method. Given the absence of evidence for new flavor-changing physics, we use the same methodology to determine the conventional atmospheric muon neutrino flux above 100 GeV.« less
  • The AMANDA-II detector, operating since 2000 in the deep ice at the geographic South Pole, has accumulated a large sample of atmospheric muon neutrinos in the 100 GeV to 10 TeV energy range. The zenith angle and energy distribution of these events can be used to search for various phenomenological signatures of quantum gravity in the neutrino sector, such as violation of Lorentz invariance or quantum decoherence. Analyzing a set of 5511 candidate neutrino events collected during 1387 days of livetime from 2000 to 2006, we find no evidence for such effects and set upper limits on violation of Lorentzmore » invariance and quantum decoherence parameters using a maximum likelihood method. Given the absence of evidence for new flavor-changing physics, we use the same methodology to determine the conventional atmospheric muon neutrino flux above 100 GeV.« less
  • A suppression in the spectrum of ultrahigh-energy (UHE, {ge} 10{sup 18} eV) neutrinos will be present in extra-dimensional scenarios, due to enhanced neutrino-antineutrino annihilation processes with the supernova relic neutrinos. In this scenario, neutrinos can not be responsible for the highest energy events observed in the UHE cosmic ray spectrum. A direct implication of these extra-dimensional interactions would be the absence of UHE neutrinos in ongoing and future neutrino telescopes.
  • We present new limits on ultrahigh energy neutrino fluxes above 10{sup 17} eV based on data collected by the Radio Ice Cherenkov Experiment (RICE) at the South Pole from 1999-2005. We discuss estimation of backgrounds, calibration and data analysis algorithms (both online and offline), procedures used for the dedicated neutrino search, and refinements in our Monte Carlo (MC) simulation, including recent in situ measurements of the complex ice dielectric constant. An enlarged data set and a more detailed study of hadronic showers results in a sensitivity improvement of more than 1 order of magnitude compared to our previously published results.more » Examination of the full RICE data set yields zero acceptable neutrino candidates, resulting in 95% confidence-level model-dependent limits on the flux E{sub {nu}}{sup 2}d{phi}/dE{sub {nu}}<10{sup -6} GeV/(cm{sup 2} s sr) in the energy range 10{sup 17}<E{sub {nu}}<10{sup 20} eV. The new RICE results rule out the most intense flux model projections at 95% confidence level.« less
  • The detection of Earth-skimming tau neutrinos has turned into a very promising strategy for the observation of ultra-high-energy cosmic neutrinos. The sensitivity of this channel crucially depends on the parameters of the propagation of the tau neutrinos through the terrestrial crust, which governs the flux of emerging tau leptons that can be detected. One of the characteristics of this propagation is the possibility of regeneration through multiple {nu}{sub {tau}}{r_reversible}{tau} conversions, which are often neglected in the standard picture. In this paper, we solve the transport equations governing the {nu}{sub {tau}} propagation and compare the flux of emerging tau leptons obtainedmore » allowing regeneration or not. We discuss the validity of the approximation of neglecting the {nu}{sub {tau}} regeneration using different scenarios for the neutrino-nucleon cross sections and the tau energy losses.« less