Relation between quiet-time low energy particle fluxes and chromospheric activity

V. N. Ishkov, K. Kecskemety, Yu I. Logachev, M. A. Zeldovich

Research output: Contribution to conferencePaper


The relation of quiet-time fluxes of 0.3-8 MeV/n protons and helium nuclei with parameters of solar activity is studied over 3 solar cycles using IMP 8 and SOHO data. Quiet periods were selected requiring a) 1 MeV proton intensity should not exceed 10-1 protons/cm2 s sr MeV at least for 2 days; b) no flare above soft X-ray class C1 should be observed during that period and one day before. Positive correlation is found between quiet-time fluxes and the background X-ray and radio emission 10.7 cm fluxes. The closest correlation is found between particle fluxes and the value of the MgII core-to-wing ratio (the MgII index) i.e. a measure of chromospheric activity. During the 21st and 23rd SC minima both the particle fluxes and the MgII index are found to be lower than their corresponding values at the 22nd SC minimum revealing the influence of 22-year magnetic solar cycle. During other phases of solar activity the lowest particle fluxes were preceded (or were observed simultaneously) by the lowest values of the MgII index. These intervals also exhibited lower values of the H/He ratio than other quiettime periods. Our previous studies indicated that at 1 AU the quiet-time particle fluxes are of solar (predominantly flare) origin throughout the solar cycle except minimum. A possible assumption is that the lowest particle fluxes originate from small active processes in the solar chromosphere and/or in the quiet low corona.

Original languageEnglish
Publication statusPublished - Jan 1 2009
Event31st International Cosmic Ray Conference, ICRC 2009 - Lodz, Poland
Duration: Jul 7 2009Jul 15 2009


Other31st International Cosmic Ray Conference, ICRC 2009



  • Solar quiet-time particles

ASJC Scopus subject areas

  • Nuclear and High Energy Physics

Cite this

Ishkov, V. N., Kecskemety, K., Logachev, Y. I., & Zeldovich, M. A. (2009). Relation between quiet-time low energy particle fluxes and chromospheric activity. Paper presented at 31st International Cosmic Ray Conference, ICRC 2009, Lodz, Poland.