MHD-simulation of corotating interaction regions in the heliosphere using different boundary conditions and codes

The paper presents the results of MHD modeling of corotating interaction regions (CIRs) at distances of 0.1 AU from the Sun (inner boundary) to much larger distances (20–30 AU) in two variants in which the magnetic field on the photosphere (1) is determined from a detailed synoptic map and (2) is represented only by the dipole component. The calculations are made for Carrington rotation 2066 (January–February 2008), using two independent software packages of Russian and Chinese groups. The time period under study is characterized by the presence of long-lived coronal holes on the Sun and a stable recurrent variation in heliosphere characteristics, as well as in the intensity of galactic cosmic rays. We discuss the advantages and disadvantages of modeling CIRs by detailed and dipole models of the photospheric magnetic field, as well as with the two mentioned software packages. The mechanisms of formation and evolution of CIRs with distance in the two models are compared and correlated to the conclusions of our previous works.