Two Minima Coronal transient Events: Their Solar Sources and Interplanetary Counterparts

CREMADES, H.; MANDRINI, C.H.; DASSO, S.

Foz do Iguacu

Congreso; 2010 American Geophysical Union Meeting of the Americas; 2010

AGU

In the frame of two coordinated observational and research efforts, two full solar rotations were investigated in times of two distinct solar minima. These two campaigns were dubbed Whole Sun Month (WSM; August 10 - September 8, 1996) and Whole Heliosphere Interval (WHI; March 20 - April 16, 2008). The nearly uninterrupted gathering of solar coronal data since the beginning of the SOHO era offers the exceptional possibility of comparing two solar minima for the first time, with regard to the coronal transient aspect. This study characterizes the variety of outward-travelling transients observed in the solar corona during both time intervals, from very narrow jet-like events to coronal mass ejections (CMEs). Their solar source regions and ensuing interplanetary (IP) structures were identified and characterized as well, towards a global-scale description of their role in determining the heliosphere?s conditions. Multi-wavelength images provided by the space missions SOHO, Yohkoh (only WSM), and STEREO (only WHI) and ground-based observatories were analyzed for coronal ejecta and their solar sources, while data registered by the Wind and ACE spacecraft were inspected for interplanetary CMEs and magnetic clouds. Notable differences arise from the analysis of the detailed survey of events: more (less) ejecta during WHI (WSM), less than 20 % (more than 40%) were produced by active regions during WHI (WSM), nearly no (high) deflection during WHI (WSM). Instrumental aspects such as dissimilar resolution, cadence, and fields of view are considered in order to discern instrumentally-driven disparities from inherent differences between both solar minima.