High Energy Astrophysics
Homework #1 - due August 31
1. A group designing a mission to survey the X-ray sky in the 10-30
keV
band decides to use silicon detectors. They require a detector
which is at least 40% efficient at 30 keV. How thick must the
silicon be?
2. Given the silicon detector from the previous question and
assuming
that the diffuse X-ray background has a flux of 1.3 photons cm-2
s-1 sr-1 in the 10-30 keV band, the detector
particle background rate is 0.1 events cm-2 s-1,
the detector area is 10,000 cm2, and the field of view of
the detector is 20° by 20°, what is the limiting sensitivity in
units of ergs cm-2 s-1 for a 5 sigma source
detection in a 1000 s observation? In a 100,000 s observation?
3. An X-ray instrument is designed to study Fe K line emission and
requires a resolution of 20 eV. What sort of detector should
be
used? Explain why.
4. You are designing a space-based instrument to detect gamma-rays
around 1 GeV. With the initial photon interaction likely be
photoelectron, Compton, or pair production?