675 research outputs found
7 Transboundary Movement of Recyclable Resources: Current Management System and Practices in Japan
The EHE Neutrino Search Capability of the IceCube Observatory
An initial study of the extremely high energy (EHE) physics capabilityof the
IceCube neutrino observatory is demonstrated by considering a GZK mechanism
neutrino production model, which is a guaranteed source for EHE neutrinos. We
study EHE event properties in the energy range E GeV
observed by IceCube using detailed Monte Carlo simulation. Results of a
simulation study show that about 0.7 EHE neutrino events per year is expected
with the full IceCube configuration over a 0.03 atmospheric muon background
which passed an EHE event criteria. It is also shown that with the present
partial IceCube detector with the same criteria is capable of studying EHE
physics and the sensitivity improves with the number of deployed strings in the
ice.Comment: Proceedings of the Cosmic Ray International Seminar (CRIS 2006) on
UHECR: Status and Perspective
Constraints on the origin of the ultra-high energy cosmic-rays using cosmic diffuse neutrino flux limits: An analytical approach
Astrophysical neutrinos are expected to be produced in the interactions of
ultra-high energy cosmic-rays with surrounding photons. The fluxes of the
astrophysical neutrinos are highly dependent on the characteristics of the
cosmic-ray sources, such as their cosmological distributions. We study possible
constraints on the properties of cosmic-ray sources in a model-independent way
using experimentally obtained diffuse neutrino flux above 100 PeV. The
semi-analytic formula is derived to estimate the cosmogenic neutrino fluxes as
functions of source evolution parameter and source extension in redshift. The
obtained formula converts the upper-limits on the neutrino fluxes into the
constraints on the cosmic-ray sources. It is found that the recently obtained
upper-limit on the cosmogenic neutrinos by IceCube constrains the scenarios
with strongly evolving ultra-high energy cosmic-ray sources, and the future
limits from an 1 km^3 scale detector are able to further constrain the
ultra-high energy cosmic-rays sources with evolutions comparable to the cosmic
star formation rate.Comment: 9 pages, 3 figures and 1 table. Accepted by Phys. Rev.
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