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Title: Energy Spectra of Abundant Cosmic-ray Nuclei in Sources, According to the ATIC Experiment

Abstract

One of the main results of the ATIC (Advanced Thin Ionization Calorimeter) experiment is a collection of energy spectra of abundant cosmic-ray nuclei: protons, He, C, O, Ne, Mg, Si, and Fe measured in terms of energy per particle in the energy range from 50 GeV to tens of teraelectronvolts. In this paper, the ATIC energy spectra of abundant primary nuclei are back-propagated to the spectra in sources in terms of magnetic rigidity using a leaky-box approximation of three different GALPROP-based diffusion models of propagation that fit the latest B/C data of the AMS-02 experiment. It is shown that the results of a comparison of the slopes of the spectra in sources are weakly model dependent; therefore the differences of spectral indices are reliable data. A regular growth of the steepness of spectra in sources in the range of magnetic rigidity of 50–1350 GV is found for a charge range from helium to iron. This conclusion is statistically reliable with significance better than 3.2 standard deviations. The results are discussed and compared to the data of other modern experiments.

Authors:
; ;  [1]
  1. Moscow State University, Skobeltsyn Institute of Nuclear Physics, Moscow, 119991 (Russian Federation)
Publication Date:
OSTI Identifier:
22661314
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 837; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCELERATION; APPROXIMATIONS; CARBON; COMPARATIVE EVALUATIONS; COSMIC RADIATION; DIFFUSION; ENERGY SPECTRA; GEV RANGE; HELIUM; IRON; MAGNESIUM; MAGNETIC RIGIDITY; NEON; NUCLEI; OXYGEN; PROTONS; SHOWER COUNTERS; SILICON

Citation Formats

Panov, A. D., Sokolskaya, N. V., and Zatsepin, V. I., E-mail: panov@dec1.sinp.msu.ru. Energy Spectra of Abundant Cosmic-ray Nuclei in Sources, According to the ATIC Experiment. United States: N. p., 2017. Web. doi:10.3847/1538-4357/AA6041.
Panov, A. D., Sokolskaya, N. V., & Zatsepin, V. I., E-mail: panov@dec1.sinp.msu.ru. Energy Spectra of Abundant Cosmic-ray Nuclei in Sources, According to the ATIC Experiment. United States. doi:10.3847/1538-4357/AA6041.
Panov, A. D., Sokolskaya, N. V., and Zatsepin, V. I., E-mail: panov@dec1.sinp.msu.ru. Wed . "Energy Spectra of Abundant Cosmic-ray Nuclei in Sources, According to the ATIC Experiment". United States. doi:10.3847/1538-4357/AA6041.
@article{osti_22661314,
title = {Energy Spectra of Abundant Cosmic-ray Nuclei in Sources, According to the ATIC Experiment},
author = {Panov, A. D. and Sokolskaya, N. V. and Zatsepin, V. I., E-mail: panov@dec1.sinp.msu.ru},
abstractNote = {One of the main results of the ATIC (Advanced Thin Ionization Calorimeter) experiment is a collection of energy spectra of abundant cosmic-ray nuclei: protons, He, C, O, Ne, Mg, Si, and Fe measured in terms of energy per particle in the energy range from 50 GeV to tens of teraelectronvolts. In this paper, the ATIC energy spectra of abundant primary nuclei are back-propagated to the spectra in sources in terms of magnetic rigidity using a leaky-box approximation of three different GALPROP-based diffusion models of propagation that fit the latest B/C data of the AMS-02 experiment. It is shown that the results of a comparison of the slopes of the spectra in sources are weakly model dependent; therefore the differences of spectral indices are reliable data. A regular growth of the steepness of spectra in sources in the range of magnetic rigidity of 50–1350 GV is found for a charge range from helium to iron. This conclusion is statistically reliable with significance better than 3.2 standard deviations. The results are discussed and compared to the data of other modern experiments.},
doi = {10.3847/1538-4357/AA6041},
journal = {Astrophysical Journal},
number = 1,
volume = 837,
place = {United States},
year = {Wed Mar 01 00:00:00 EST 2017},
month = {Wed Mar 01 00:00:00 EST 2017}
}
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