Answer:
Explanation:
Complete Question:
A.Compute no of electrons you expect to count if silicon detector is struck with a 1.04 Mev gamma ray produced in a decay of 136 Cs nucleus.
b.Explain counting of electrons is more precise as the detector is cooled well below room temperature
Answer:
a.
Gamma ray energy =
photon strikes the surface excite the electrons to move from valence band to conduction band where then counted by detector.
energy gap between valence band and conduction band in case of silicon = 1.1 eV
The minimum amount of energy required is 1.1 ev
minimum number of electron counted is =
=
b.
In the case of semi conductors
forbidden energy gap in inversely proportional to temperature
with decrease in temperature forbidden energy gap increases,hence electrons jumping from valence band to conduction band decreases and hence counting by detector decreases