Variability of Cosmic Ray Power Spectra
Variability of the power spectra of cosmic ray temporal profiles in the frequency interval 1.2 × 10<SUP>-5</SUP> Hz (<I>f</I><SUB>1</SUB>) to 1.7 × 10<SUP>-3</SUP> Hz (<I>f</I><SUB>2</SUB>) in the period of two years shows that the integrals of power spectrum density over the interval <I>f</I><SUB>1</SUB> to 2.8 × 10<SUP>-4</SUP> Hz (<I>P</I><SUB>1</SUB>) are significantly correlated at two neutron monitors differing inacceptance cones and cut-off rigidities. At high frequency region, J>2.8 × 10<SUP>-4</SUP>Hz, the integrals <I>P</I><SUB>2</SUB> are correlated much less. <I>P</I><SUB>1</SUB> are weakly correlated with the cosmic ray intensity itself. Cross correlation between the time series <I>P</I><SUB>1</SUB> and the daily averages of geomagnetic indices (<I>Kp</I>, <I>Dst</I> and <I>Ap</I>) is asymmetric, with the maximum shifted to positive time lag. This indicates the stronger relation of the daily averaged geomagnetic indices measured for given day with the <I>P</I><SUB>1</SUB> obtained a day before, than with the <I>P</I><SUB>1</SUB> at the same day. The shift is not obtained if cosmic ray intensity, instead of <I>P</I><SUB>1</SUB>, is cross-correlated with geomagnetic indices.
- Journal of geomagnetism and geoelectricity
Journal of geomagnetism and geoelectricity 48(8), 1017-1024, 1996-08
Society of Geomagnetism and Earth, Planetary and Space Sciences