NuSTAR's First Solar Observations
Solar Physics General Session
Iain G. Hannah
University of Glasgow
D. Smith, A. Marsh (Santa Cruz), L. Glesener (UC Berkeley), S. Krucker (& FHNW), H. Hudson (& Glasgow), B. Grefenstette, K. Madsen, R. Mewaldt (Caltech), S. White (AFRL), A. Shih, S. Christe (GSFC), A. Caspi (SWRI), M. Pivovaroff, J. Vogel (LLNL)
We present imaging spectroscopy of the Sun with the NuSTAR hard X-ray (HXR) telescope, searching for high temperature and non-thermal emission in the “non-flaring” Sun. Launched in 2012, NASA's astrophysics mission NuSTAR uses focusing optics to directly image X-rays between ~2-80 keV. In the band below ~50 keV the field of view is 12'x12' and the instrument has an energy resolution of ~0.4 keV. Although not optimized for solar observations, NuSTAR’s high sensitivity can probe previously inaccessible X-ray emission from the Sun. For instance the weak X-ray signatures of a coronal energy release region in occulted flares or searching for the non-thermal emission from “nanoflares” in non-flaring active regions and the quiet Sun. NuSTAR observed the Sun three times during late 2014 and we present these first directly imaged hard X-rays from non-flaring active regions. Using NuSTAR’s imaging spectroscopy capabilities we are able to derive the active region’s multi-thermal characteristics. We will also discuss a hot (>3MK) source that appears to linger high in the corona and could be associated with the occulted active region AR12192.
09:00 - 10:30