817 research outputs found
Proceedings of the First Workshop on Exotic Physics with Neutrino Telescopes, EPNT06
The first Workshop on Exotic Physics with Neutrino Telescopes was held in
Uppsala, Sweden, between September 20-22, 2006.
The workshop was based on talks giving an overview of relevant subjects both
from experiments and theorists. The theory talks provided guidelines for
experimental searches, and covered the signatures expected in neutrino
telescopes from different dark matter candidates, micro black holes, models
with extra dimensions, non--standard neutrino oscillation scenarios and new
neutrino interactions. The existing and planned neutrino telescopes presented
their results and perspectives on the mentioned subjects.Comment: 28 contributions, 164 pages. C. de los Heros (editor
Including Systematic Uncertainties in Confidence Interval Construction for Poisson Statistics
One way to incorporate systematic uncertainties into the calculation of
confidence intervals is by integrating over probability density functions
parametrizing the uncertainties. In this note we present a development of this
method which takes into account uncertainties in the prediction of background
processes, uncertainties in the signal detection efficiency and background
efficiency and allows for a correlation between the signal and background
detection efficiencies. We implement this method with the Feldman & Cousins
unified approach with and without conditioning. We present studies of coverage
for the Feldman & Cousins and Neyman ordering schemes. In particular, we
present two different types of coverage tests for the case where systematic
uncertainties are included. To illustrate the method we show the relative
effect of including systematic uncertainties the case of dark matter search as
performed by modern neutrino tel escopes.Comment: 23 pages, 10 figures, replaced to match published versio
Testing the Dark Matter Interpretation of the DAMA/LIBRA Result with Super-Kamiokande
We consider the prospects for testing the dark matter interpretation of the
DAMA/LIBRA signal with the Super-Kamiokande experiment. The DAMA/LIBRA signal
favors dark matter with low mass and high scattering cross section. We show
that these characteristics imply that the scattering cross section that enters
the DAMA/LIBRA event rate determines the annihilation rate probed by
Super-Kamiokande. Current limits from Super-Kamiokande through-going events do
not test the DAMA/LIBRA favored region. We show, however, that upcoming
analyses including fully-contained events with sensitivity to dark matter
masses from 5 to 10 GeV may corroborate the DAMA/LIBRA signal. We conclude by
considering three specific dark matter candidates, neutralinos, WIMPless dark
matter, and mirror dark matter, which illustrate the various model-dependent
assumptions entering our analysis.Comment: 10 pages, 1 figure; v2: projected super-K sensitivity corrected and
strengthened, references added; v3: published versio
Low-mass e+e- pair production in 158 A GeV Pb-Au collisions at the CERN SPS, its dependence on multiplicity and transverse momentum
We report a measurement of low-mass electron pairs observed in 158
GeV/nucleon Pb-Au collisions. The pair yield integrated over the range of
invariant masses 0.2 < m < 2.0 GeV is enhanced by a factor of 3.5 +/- 0.4
(stat) +/- 0.9 (syst) over the expectation from neutral meson decays. As
observed previously in S-Au collisions, the enhancement is most pronounced in
the invariant-mass region 300-700 MeV. For Pb-Au we find evidence for a strong
increase of the enhancement with centrality. In addition, we show that the
enhancement covers a wide range in transverse momentum, but is largest at the
lowest observed pt.Comment: 17 pages, 4 figures, submitted to Phys.Lett.
The AMANDA Neutrino Telescope and the Indirect Search for Dark Matter
With an effective telescope area of order 10^4 m^2, a threshold of ~50 GeV
and a pointing accuracy of 2.5 degrees, the AMANDA detector represents the
first of a new generation of high energy neutrino telescopes, reaching a scale
envisaged over 25 years ago. We describe its performance, focussing on the
capability to detect halo dark matter particles via their annihilation into
neutrinos.Comment: Latex2.09, 16 pages, uses epsf.sty to place 15 postscript figures.
Talk presented at the 3rd International Symposium on Sources and Detection of
Dark Matter in the Universe (DM98), Santa Monica, California, Feb. 199
e+e--pair production in Pb-Au collisions at 158 GeV per nucleon
We present the combined results on electron-pair production in 158 GeV/n
{Pb-Au} (= 17.2 GeV) collisions taken at the CERN SPS in 1995 and
1996, and give a detailed account of the data analysis. The enhancement over
the reference of neutral meson decays amounts to a factor of 2.31 for semi-central collisions (28%
) when yields are integrated over 200 MeV/ in
invariant mass. The measured yield, its stronger-than-linear scaling with
, and the dominance of low pair strongly suggest an
interpretation as {\it thermal radiation} from pion annihilation in the
hadronic fireball. The shape of the excess centring at 500
MeV/, however, cannot be described without strong medium modifications of
the meson. The results are put into perspective by comparison to
predictions from Brown-Rho scaling governed by chiral symmetry restoration, and
from the spectral-function many-body treatment in which the approach to the
phase boundary is less explicit.Comment: 39 pages, 40 figures, to appear in Eur.Phys.J.C. (2005
Measurement of negative particle multiplicity in S - Pb collisions at 200 GeV/c per nucleon with the NA36 TPC
A high statistics study of the negative multiplicity distribution from S-Pb collisions at 200 GeV/c per nucleon is presented. The NA36 TPC was used to detect charged particles; corrections are based upon the maximum entropy method.A high statistics study of the negative multiplicity distribution from S-Pb collisions at 200 GeV/c per nucleon is presented. The NA36 TPC was used to detect charged particles; corrections are based upon the maximum entropy method.A high statistics study of the negative particle multiplicity distribution from S–Pb collisions at 200 GeV/ c per nucleon is presented. The NA36 TPC was used to detect charged particles; corrections are based upon the maximum entropy method
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