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Title: New physics from ultrahigh energy cosmic rays

Abstract

Cosmic rays from outer space enter the atmosphere with energies of up to 10{sup 11} GeV. The initial particle or a secondary hadron inside the shower may then interact with an air nucleon to produce nonstandard particles. In this article we study the production of new physics by high energy cosmic rays, focusing on the long-lived gluino of split-SUSY models and a weakly interacting massive particle (WIMP) working as dark matter. We first deduce the total flux of hadron events at any depth in the atmosphere, showing that secondary hadrons can not be neglected. Then we use these results to find the flux of gluinos and WIMPs that reach the ground after being produced inside air showers. We also evaluate the probability of producing these exotic particles in a single proton shower of ultrahigh energy. Finally we discuss the possible signal in current and projected experiments. While the tiny flux of WIMPs does not seem to have any phenomenological consequences, we show that the gluinos could modify substantially the profile of a small fraction of extensive air showers. In particular, they could produce a distinct signal observable at AUGER in showers of large zenith angle.

Authors:
;  [1];  [2]
  1. CAFPE and Depto. de Fisica Teorica y del Cosmos, Universidad de Granada, 18071 Granada (Spain)
  2. INFN and Dipto. di Fisica, Universita degli Studi di Roma 'La Sapienza', 00185 Rome (Italy)
Publication Date:
OSTI Identifier:
21020087
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevD.75.055002; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ENERGY SPECTRA; EXTENSIVE AIR SHOWERS; NONLUMINOUS MATTER; PARTICLE IDENTIFICATION; PARTICLE INTERACTIONS; PARTICLE PRODUCTION; PEV RANGE; SPARTICLES; SUPERSYMMETRY; WEAK INTERACTIONS

Citation Formats

Illana, J. I., Masip, M., and Meloni, D. New physics from ultrahigh energy cosmic rays. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.055002.
Illana, J. I., Masip, M., & Meloni, D. New physics from ultrahigh energy cosmic rays. United States. doi:10.1103/PHYSREVD.75.055002.
Illana, J. I., Masip, M., and Meloni, D. Thu . "New physics from ultrahigh energy cosmic rays". United States. doi:10.1103/PHYSREVD.75.055002.
@article{osti_21020087,
title = {New physics from ultrahigh energy cosmic rays},
author = {Illana, J. I. and Masip, M. and Meloni, D.},
abstractNote = {Cosmic rays from outer space enter the atmosphere with energies of up to 10{sup 11} GeV. The initial particle or a secondary hadron inside the shower may then interact with an air nucleon to produce nonstandard particles. In this article we study the production of new physics by high energy cosmic rays, focusing on the long-lived gluino of split-SUSY models and a weakly interacting massive particle (WIMP) working as dark matter. We first deduce the total flux of hadron events at any depth in the atmosphere, showing that secondary hadrons can not be neglected. Then we use these results to find the flux of gluinos and WIMPs that reach the ground after being produced inside air showers. We also evaluate the probability of producing these exotic particles in a single proton shower of ultrahigh energy. Finally we discuss the possible signal in current and projected experiments. While the tiny flux of WIMPs does not seem to have any phenomenological consequences, we show that the gluinos could modify substantially the profile of a small fraction of extensive air showers. In particular, they could produce a distinct signal observable at AUGER in showers of large zenith angle.},
doi = {10.1103/PHYSREVD.75.055002},
journal = {Physical Review. D, Particles Fields},
number = 5,
volume = 75,
place = {United States},
year = {Thu Mar 01 00:00:00 EST 2007},
month = {Thu Mar 01 00:00:00 EST 2007}
}
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