Implications of Solar Magnetograms for the Drifts of Cosmic Rays

Discussion timeslot (ZOOM-Meeting): 16. July 2021 - 18:00
ZOOM-Meeting URL: https://icrc2021.desy.de/pf_access_abstracts
Corresponding Session: https://icrc2021-venue.desy.de/channel/Presenter-Forum-1-Evening-All-Categories/48
Abstract:
'While gradient and curvature drifts are well-established elements ofrnthe propagation of cosmic rays in the heliospheric magnetic field,rntheir perturbation by the solar activity-induced large-scalerndistortions of dipole-like field configurations even during solarrnminima and by magnetic turbulence is an open problem. Variousrnempirical or phenomenological approaches have been suggested tornquantify these effects so that they can be straightforwardlyrnincorporated in modulation models covering the 22-year periodicityrn(including the sign) of solar activity. These approaches, however,rneither lack clear physics-based parametrizations (e.g., in terms ofrnthe tilt-angle of the heliospheric current sheet) or have been shownrnto be incompatible with measurements (like a dependence on thernnormalized turbulence level $delta B/B$). We propose here a newrnapproach to the treatment of drifts over an entire solar cyclernincluding maximum periods, which is based on solar magnetograms. Thisrnnot only provides a physics-based approach to the reduction of driftsrnduring solar activity maxima but also a treatment that is fullyrnconsistent with those MHD models of the solar wind and the embeddedrnheliospheric magnetic field that exploit solar magnetograms as innerrnboundary conditions.'

Authors: Horst Fichtner | Andreas Kopp
Indico-ID: 704
Proceeding URL: https://pos.sissa.it/395/1342