2,731 research outputs found
Seasonal variations of the rate of multiple-muons in the Gran Sasso underground laboratory
It is well known that the rate of cosmic ray muons depends on the atmospheric
temperature, and that for events with a single muon the peak of the rate is in
summer, in underground laboratories in the northern hemisphere. In 2015 the
MINOS experiment, in USA, found that, for small distances between the
multiple-muons, the rate of multiple-muons peaks in the winter and that the
amplitude of the modulation is smaller than in the case of a single muon. I
have done a re-analysis of data of the past MACRO experiment. The result is
that under Gran Sasso the rate of multiple-muons at small distances peaks in
the summer. This difference with MINOS could be explained by differences in the
atmospheric temperature due to latitude. This results could be of interest for
dark matter experiments looking to dark matter seasonal modulation due to the
Earth's motion.Comment: presented to the RICAP 2016 conferenc
New distributed offline processing scheme at Belle
The offline processing of the data collected by the Belle detector has been
recently upgraded to cope with the excellent performance of the KEKB
accelerator. The 127/fb of data (120 TB on tape) collected between autumn 2003
and summer 2004 has been processed in 2 months, thanks to the high speed and
stability of the new, distributed processing scheme. We present here this new
processing scheme and its performance.Comment: 4 pages, 8 figures, uses CHEP2004.cl
Detection of high energy cosmic rays with the resonant gravitational wave detectors NAUTILUS and EXPLORER and comparison with the direct measurements with an aluminum superconductive bar
The cryogenic resonant gravitational wave detectors NAUTILUS and EXPLORER, made of an aluminum alloy bar, can detect cosmic ray showers. At temperatures above 1 K, when the material is in the normal conducting state, the measured signals are in good agreement with the values expected based on the cosmic rays data and on the thermo-acoustic model. When NAUTILUS was operated at the temperature of 0.14 K, in superconductive state, large signals produced by cosmic ray interactions, more energetic than expected, were recorded. The NAUTILUS data in this case are in agreement with the measurements done by a dedicated experiment on a particle beam. The largest event detected up to now has an energy in the first longitudinal mode of ∼ 670 K corresponding to ∼ 360 TeV in the bar
Neutrino long base line experiments in Europe
A short summary of the past, present and future neutrino experiments in Europe is given. The main emphasis is on long base line accelerator experiments
Search for a possible space-time correlation between high energy neutrinos and -ray bursts
We look for space-time correlations between 2233 gamma-bursts in the Batse Catalogs and 894 upward-going muons produced by neutrino interactions in the rock below or inside MACRO. Considering a search cone of 10 degrees around GRB directions and a time window of 200 s we find 0 events to be compared to 0.035 expected background events due to atmospheric neutrinos. The corresponding upper limit (90% c.l.) is 0.87 * 10^-9 cm^-2 upward-going muons per average burst
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