Mica Observations of Coronal Transients

Dynamical processes are well known to occur in the inner solar atmosphere, many of them giving origin to spectacular eruptions known as coronal mass ejections (CMEs). The projected speed of propagation of these events ranges from less than 100 km/sec to greater than 1200 km/sec. In order to study the initial evolution of the faster processes it is necessary to image the inner corona at a very high cadence. Although ground-based observations of the solar corona are strongly a ected by sky conditions they allow imaging at a high temporal resolution as compared to coronagraphic observations from space. In the recently inaugurated German-Argentinean Solar-Observatory at El Leoncito, San Juan, Argentina, a mirror coronagraph (MICA) daily images the inner solar corona with high temporal and spatial resolution in two spectral ranges: the well known green (1:8 10 K) and red (1:0 10 K) coronal lines at 5303 A and 6374 A respectively. It is essentially similar in design to LASCO-C1 on board SOHO, its eld-of-view ranging from 1:05 to 2:0 solar radii. Thus it is ideally suited to observe the hot material and reveal the fast processes that occur in the coronal plasma. In this work we will present observations of a few such events. This study would allow us to have a better understanding of the conditions that trigger the coronal mass ejections and their propagation in the inner solar corona.