High-Energy Sky

Question 1

How can X-rays be detected?

Answer 1

grazing incidence reflections using a nested shell of mirrors (increases collecting area).

Question 2

What device is used to detect gamma rays in the 1-30 MeV range?

Answer 2

Compton telescope.

Question 3

What device is used to detect gamma rays in the 30 MeV - 30 GeV range?

Answer 3

Pair Conversion detector.

Question 4

What device is used to detect gamma rays in the 100 GeV - 100 TeV range?

Answer 4

Cherenkov Telescope.

Question 5

How does a Compton telescope work?

Answer 5

detects the direction of source photons using the change in energy from a deflection and then the angle between that deflection and detection.

Question 6

What is a pair conversion detector?

Answer 6

layers of silicon interleaved with tungsten which triggers pair production.

Question 7

How does a pair conversion detector work?

Answer 7

follow the trajectory of e+/- to reconstruct arrival direction. Can also measure energy of e+/-.

Question 8

What is Cherenkov radiation?

Answer 8

It is emitted when something moves into a medium in which v>c/n.

Question 9

How can we detect Cherenkov radiation?

Answer 9

Use the Earth’s atmosphere. Record images using arrays of telescopes ~100m apart to locate source.