Correlation of the quasi-biennial oscillations in galactic cosmic rays and in the solar activity indices

Abstract

Quasi-biennial oscillation (QBO) is a well-known variation in solar activity, interplanetary parameters, geomagnetic disturbances and cosmic rays. Solar QBO is translated to the space via open magnetic flux and modulates intensity of cosmic rays. The highest negative correlation exists in the QBO of cosmic rays with QBO in the heliospheric magnetic field strength B as well as with QBO in the scalar product BV, where V is the solar wind velocity, cosmic ray being delayed by ≈ 1 month. During ≈ 50 years of cosmic ray monitoring the QBO periods demonstrated some intermittency. It is argued that the Gnevyshev Gap effect and the step-like changes in the cosmic ray intensity appeared to be a part of QBO in cosmic rays.