Variation of cosmic rays and solar wind properties with respect to the heliospheric current sheet: 2. Rigidity dependence of the latitudinal gradient of cosmic rays at 1 AU

We discuss the role which empirical determinations of the latitudinal variation of cosmic rays with respect to the current sheet may have in illuminating the importance of the cross‐field drift of particles in the large‐scale heliospheric magnetic field. Using K coronameter observations and measured solar wind speeds, we have determined the latitudinal gradients with respect to the current sheet for cosmic rays in four rigidity ranges. Gradients vary between approximately −2 and −50% per astronomical unit. The rigidity dependence of the decrease of cosmic ray flux with distance from the current sheet lies between P −0.72 and P −0.86 , with the exact dependence being determined by the definition used for the median rigidity of each monitor.