HEROES will observe the Sun with unprecedented sensitivity and dynamic range by applying new hard X-ray focusing optics to solar observations for the first time. The most sensitive solar hard X-ray observations are currently provided by the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) and are obtained using a non- focusing imaging technique. Such indirect imaging, however, has intrinsically limited dynamic range and sensitivity, while through direct imaging, these limitations can be overcome. HEROES will provide new hard x-ray observations of the Sun with 100 times better sensitivity and 50 times more dynamic range than RHESSI. HEROES will:
- test theories of particle acceleration in solar flares
- investigate the possibility of nanoflare coronal heating by searching for signatures of energetic electrons in the non-flaring corona
- measure the x-ray flux reflected from the solar photosphere (albedo) during solar flares
This novel instrument will provide new views (improved angular resolution) of hard X-ray astrophysical targets. The hard X-ray band is a region where non-thermal processes dominate the emission. This energy region is still relatively unexplored with high sensitivity at fine spatial scales. The high angular resolution afforded by focusing optics is essential for mitigating source confusion in crowded fields and for direct imaging of extended sources. HEROES will:
- measure the angular extent of the crab Nebula
- investigate flaring and the long-term variability of the crab Nebula
- identify non-thermal components of Galactic X-ray binaries.