On connection of dynamics of active solar regions and hard cosmic ray flux variation

Abstract

The problem of connection between Solar activity and hard cosmic ray flux (HCRF) change near ground surface was investigated. Solar activity is characterized by Wolf number, as well as number size and location of active solar regions on the solar disc. The measurements of HCRF were carried out by gamma-spectrometer with scintillation detector in Vilnius city in 2006-2008. Data on solar activity were obtained from the Mees Solar Observatory website. The connection between tendencies of course of HCRF, Wolf number and number of active regions (NAR) is defined. The correlation coefficient between HCRF and NAR was higher than between HCRF and Wolf number. The correlation coefficient between NAR and HCRF in 2008 was equal to 0.71. The correlation coefficient between HCRF and Wolf number was lower, i.e. 0.61. There were found leaps of HCRF in 2006.11, 2007.01 and 2008.03. Leaps of NAR and Wolf number were registered in the same months. The same course of HCRF and NAR is obtained. However, the tendency of course of HCRF was 3 months ahead in comparison with NAR in 2006-2007 and one month ahead during 2008.