12 research outputs found

    Possible structure in the cosmic ray electron spectrum measured by the ATIC-2 and ATIC-4 experiments

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    A strong excess in a form of a wide peak in the energy range of 300-800 GeV was discovered in the first measurements of the electron spectrum in the energy range from 20 GeV to 3 TeV by the balloon-borne experiment ATIC (J. Chang et al. Nature, 2008). The experimental data processing and analysis of the electron spectrum with different criteria for selection of electrons, completely independent of the results reported in (J. Chang et al. Nature, 2008) is employed in the present paper. The new independent analysis generally confirms the results of (J. Chang et al. Nature, 2008), but shows that the spectrum in the region of the excess is represented by a number of narrow peaks. The measured spectrum is compared to the spectrum of (J. Chang et al. Nature, 2008) and to the spectrum of the Fermi/LAT experiment.Comment: LaTeX2e, 10 pages, 4 figures, a paper for ECRS 2010 (Turku, Finland); http://www.astrophys-space-sci-trans.net/7/119/2011

    Energy dependence of Ti/Fe ratio in the Galactic cosmic rays measured by the ATIC-2 experiment

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    Titanium is a rare, secondary nucleus among Galactic cosmic rays. Using the Silicon matrix in the ATIC experiment, Titanium has been separated. The energy dependence of the Ti to Fe flux ratio in the energy region from 5 GeV per nucleon to about 500 GeV per nucleon is presented.Comment: 8 pages, 4 figures, accepted for publication in Astronomy Letter

    Systematics in the Electron Spectrum Measured by ATIC

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    An analysis of different parameters to separate electrons from protons in the ATIC experiment has been performed. Five separate discriminants were studied by different Monte Carlo programs, leading to a variety of results. Application to the ATIC data indicates the range of variation possible in the interpretation of the data. The results of this analysis, when compared with the published results [5], show good agreement in the most interesting region of energy (from 90 GeV to 600 GeV). The measured electron spectrum is compared with the recent data reported by Fermi/LAT, and there is no major disagreement between ATIC s results and Fermi/LAT. Finally, possible systematics-free, short energy scale features of the ATIC electron spectrum are mentioned. Keywords: ATIC, electron spectrum, fine structur

    LONG-TERM CHANGES IN POLLUTION OF THE MARINE ENVIRONMENT IN THE SHOAL ZONE OF THE WESTERN PART OF THE NORTHERN CASPIAN SEA

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    The provides long-term data ĐŸŃ‚ the state of the medium shallow waters west of the North Caspian

    Status of the ATIC experiment

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    The ATIC collaboration has constructed a spectrometer for measuring the energy spectra of Galactic cosmic rays with an individual charge resolution from protons to nickel in the energy range from about 5*10 /sup 10/ eV to about 10/sup 14/ eV. In September 1999, the ATIC was calibrated at CERN, and is currently ready for operation. The first long-term flight around the South Pole is scheduled for December 2000. (10 refs)
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