Cosmic Ray Flux Variation Estimated from the Raw Solar Images

  • Oh, Suyeon (Department of Astronomy and Space Science, Chungnam National University) ;
  • Park, Hyungmin (Astronomy Program, Physics and Astronomy, Seoul National University) ;
  • Park, Keunchan (Department of Astronomy and Space Science, Chungnam National University) ;
  • Chae, Jongchul (Astronomy Program, Physics and Astronomy, Seoul National University) ;
  • Yi, Yu (Department of Astronomy and Space Science, Chungnam National University)
  • Published : 2013.10.08

Abstract

The solar images are taken by the CCD detectors of the Sun monitoring satellites. The solar images are constructed after removing the traces of cosmic rays on the raw CCD data files. Thus, while applying the method of removing the cosmic rays traces, we can estimate the cosmic rays flux by counting the number of traces. The cosmic ray flux in the steady state might be the sum of the solar and galactic cosmic rays. However, the abrupt change in the flux could be assumed to be originated from the Sun. Therefore, we can identify the solar origins of the sudden solar cosmic ray flux changes from the phenomena shown in the processed solar images taken by SOHO/EIT. As the results, the estimated cosmic ray flux in the steady state is the anti-correlated with sunspot numbers, which shows the minima in cosmic ray flux at the solar cycle maxima defined by the sunspot numbers. The profiles of estimated solar cosmic ray associated with the ground level enhancements have the significant increase in the cosmic ray flux with good correlation. Thus, the solar images are valuable data useful in estimating the solar cosmic ray long term and transient flux variations.

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