Three-dimensional wavy heliospheric current sheet drifts

We present an analytic method to determine the directions of the three-dimensional (3D) heliospheric current sheet (HCS) drift for any tilt angle based on Parker's heliospheric magnetic field and compare it with published two-dimensional and quasi-3D methods. We also present a new approach to determine the magnitude of the 3D HCS drift numerically. Implications of these new methods for the solar modulation of Galactic cosmic rays are considered and compared with results from prior methods reported in the literature. Our results support the concept that HCS drift plays an important role in the solar modulation of cosmic rays. © 2012 The American Astronomical Society. All rights reserved.