Coronal mass ejections ( CMEs ) are thought to drive collisionless shocks in the solar corona , which in turn have been shown capable of accelerating solar energetic particles ( SEPs ) in minutes .
It has been notoriously difficult to extract information about energetic particle spectra in the corona , due to lack of in-situ measurements .
It is possible , however , to combine remote observations with data-driven models in order to deduce coronal shock properties relevant to the local acceleration of SEPs and their heliospheric connectivity to near-Earth space .
We present such novel analysis applied to the May 11 , 2011 CME event on the western solar limb , focusing on the evolution of the eruption-driven , dome-like shock wave observed by the Atmospheric Imaging Assembly ( AIA ) EUV telescopes on board the Solar Dynamics Observatory spacecraft .
We analyze the shock evolution and estimate its strength using emission measure modeling .
We apply a new method combining a geometric model of the shock front with a potential field source surface model to estimate time-dependent field-to-shock angles and heliospheric connectivity during shock passage in the low corona .
We find that the shock was weak , with an initial speed of \sim 450 km/s .
It was initially mostly quasi-parallel , but significant portion of it turned quasi-perpendicular later in the event .
There was good magnetic connectivity to near-Earth space towards the end of the event as observed by the AIA instrument .
The methods used in this analysis hold a significant potential for early characterization of coronal shock waves and forecasting of SEP spectra based on remote observations .