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Title: Proton and Helium Spectra from the CREAM-III Flight

Abstract

Primary cosmic-ray elemental spectra have been measured with the balloon-borne Cosmic Ray Energetics And Mass (CREAM) experiment since 2004. The third CREAM payload (CREAM-III) flew for 29 days during the 2007–2008 Antarctic season. Energies of incident particles above 1 TeV are measured with a calorimeter. Individual elements are clearly separated with a charge resolution of ∼0.12 e (in charge units) and ∼0.14 e for protons and helium nuclei, respectively, using two layers of silicon charge detectors. The measured proton and helium energy spectra at the top of the atmosphere are harder than other existing measurements at a few tens of GeV. The relative abundance of protons to helium nuclei is 9.53 ± 0.03 for the range of 1 TeV/n to 63 TeV/n. This ratio is considerably smaller than other measurements at a few tens of GeV/n. The spectra become softer above ∼20 TeV. However, our statistical uncertainties are large at these energies and more data are needed.

Authors:
; ; ; ; ;  [1]; ; ; ;  [2]; ;  [3]; ; ; ;  [4]; ;  [5];  [6];  [7] more »; « less
  1. Institute for Physical Science and Technology, University of Maryland, College Park, MD, 20742 (United States)
  2. Department of Physics, Penn State University, University Park, PA 16802 (United States)
  3. Laboratoire de Physique Subatomique et Cosmologie, Grenoble (France)
  4. Department of Physics, Sungkyunkwan University, Suwon 16419 (Korea, Republic of)
  5. Astrophysics Space Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)
  6. Instituto de Fisica, Universidad Nacional Autonoma de Mexico (Mexico)
  7. Department of Physics, Northern Kentucky University, Highland Heights, KY 41099 (United States)
Publication Date:
OSTI Identifier:
22661170
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 839; 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; ANTARCTIC REGIONS; CALORIMETERS; DATA ANALYSIS; ENERGY SPECTRA; GEV RANGE; HELIUM; LAYERS; MASS; NUCLEI; PRIMARY COSMIC RADIATION; PROTONS; RESOLUTION; SILICON; TEV RANGE

Citation Formats

Yoon, Y. S., Han, J. H., Kim, K. C., Kim, M. H., Lee, M. H., Lee, S. E., Anderson, T., Conklin, N. B., Coutu, S., Mognet, S. I., Barrau, A., Derome, L., Jeon, J. A., Lee, H. Y., Lee, J., Park, I. H., Link, J. T., Mitchell, J. W., Menchaca-Rocha, A., Nutter, S., and and others. Proton and Helium Spectra from the CREAM-III Flight. United States: N. p., 2017. Web. doi:10.3847/1538-4357/AA68E4.
Yoon, Y. S., Han, J. H., Kim, K. C., Kim, M. H., Lee, M. H., Lee, S. E., Anderson, T., Conklin, N. B., Coutu, S., Mognet, S. I., Barrau, A., Derome, L., Jeon, J. A., Lee, H. Y., Lee, J., Park, I. H., Link, J. T., Mitchell, J. W., Menchaca-Rocha, A., Nutter, S., & and others. Proton and Helium Spectra from the CREAM-III Flight. United States. doi:10.3847/1538-4357/AA68E4.
Yoon, Y. S., Han, J. H., Kim, K. C., Kim, M. H., Lee, M. H., Lee, S. E., Anderson, T., Conklin, N. B., Coutu, S., Mognet, S. I., Barrau, A., Derome, L., Jeon, J. A., Lee, H. Y., Lee, J., Park, I. H., Link, J. T., Mitchell, J. W., Menchaca-Rocha, A., Nutter, S., and and others. Mon . "Proton and Helium Spectra from the CREAM-III Flight". United States. doi:10.3847/1538-4357/AA68E4.
@article{osti_22661170,
title = {Proton and Helium Spectra from the CREAM-III Flight},
author = {Yoon, Y. S. and Han, J. H. and Kim, K. C. and Kim, M. H. and Lee, M. H. and Lee, S. E. and Anderson, T. and Conklin, N. B. and Coutu, S. and Mognet, S. I. and Barrau, A. and Derome, L. and Jeon, J. A. and Lee, H. Y. and Lee, J. and Park, I. H. and Link, J. T. and Mitchell, J. W. and Menchaca-Rocha, A. and Nutter, S. and and others},
abstractNote = {Primary cosmic-ray elemental spectra have been measured with the balloon-borne Cosmic Ray Energetics And Mass (CREAM) experiment since 2004. The third CREAM payload (CREAM-III) flew for 29 days during the 2007–2008 Antarctic season. Energies of incident particles above 1 TeV are measured with a calorimeter. Individual elements are clearly separated with a charge resolution of ∼0.12 e (in charge units) and ∼0.14 e for protons and helium nuclei, respectively, using two layers of silicon charge detectors. The measured proton and helium energy spectra at the top of the atmosphere are harder than other existing measurements at a few tens of GeV. The relative abundance of protons to helium nuclei is 9.53 ± 0.03 for the range of 1 TeV/n to 63 TeV/n. This ratio is considerably smaller than other measurements at a few tens of GeV/n. The spectra become softer above ∼20 TeV. However, our statistical uncertainties are large at these energies and more data are needed.},
doi = {10.3847/1538-4357/AA68E4},
journal = {Astrophysical Journal},
number = 1,
volume = 839,
place = {United States},
year = {Mon Apr 10 00:00:00 EDT 2017},
month = {Mon Apr 10 00:00:00 EDT 2017}
}
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