The Relation between Coronal Holes and CMEs during the Rise, Maximum and Declining Phases of the Solar Cycle 23
Abstract
We investigate the influence of coronal holes (CHs) on the propagation of CMEs considering both magnetic clouds (MCs) and non-magnetic clouds (non-MCs), during the three phases of the solar cycle 23. We consider events originating within a central meridian distance of 15○. The influence of the CHs is computed as a fictitious force that depends on the CH area, the distance between the CH and the eruption region, and the magnetic field within the CH at the photospheric level. We find that the influence parameter is the smallest during the rise phase of the cycle and increases during the maximum and then in the declining phases. The largest influence parameter was observed to be for non-MCs in the Maximum phase F= 2.9 G. However, the average influence parameter is only about half of what was computed for driverless shocks F= 5.8 G. The CH effect on the non-MCs is found to be larger than that for MCs during maximum phase; this may suggest that non-MCs may also have flux rope structure which is hidden from observation due to the deflection by the nearby CHs as has been suggested in the case of driverless shocks (Gopalswamy et al., 2009, JGR). reference: Gopalswamy, N., p. Makela, H. Xie, S. Akiyama, and S. Yashiro, (2009), "CME Interaction with coronal holes and their interplanetary consequences" , J. Geophys. Res., 114,A00A22 doi:10.1029/2008JA013686.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2010
- Bibcode:
- 2010AGUFMSH23B1852M
- Keywords:
-
- 2111 INTERPLANETARY PHYSICS / Ejecta;
- driver gases;
- and magnetic clouds;
- 2139 INTERPLANETARY PHYSICS / Interplanetary shocks;
- 7511 SOLAR PHYSICS;
- ASTROPHYSICS;
- AND ASTRONOMY / Coronal holes;
- 7513 SOLAR PHYSICS;
- ASTROPHYSICS;
- AND ASTRONOMY / Coronal mass ejections