HESSI Observational
Characteristics
Energy Range   3 keV to 15 MeV
Energy Resolution (FWHM)   <1 keV FWHM at 3 keV
     increasing to 5 keV at 15 MeV
Angular Resolution   2 arcseconds to 100 keV
     7 arcseconds to 400 keV
     36 arcseconds to 15 MeV
Temporal Resolution   Tens of ms for basic image
     2 s for detailed image
Field of View   Full Sun
Effective Area - cm2   10-3 at 3 keV, 50 at 10 keV
       (with attenuators out)   60 at 100 keV, 20 at 10 MeV
Numbers of flares   ~1000 imaged to >100 keV.
     ~100 with spectroscopy to ~10 MeV