OCTOBER 2017 Sub. Code: 4014
M.Sc. MEDICAL PHYSICS EXAMS
FIRST YEAR
PAPER IV RADIATION DOSIMETRY AND STANDARDIZATION
Q.P. Code 284014
Time Three hours Maximum 100 Marks
I. Elaborate on: x 20 40)
1. Explain about the IAEA TRS 398 protocol and calibration of cobalt beams using
this protocol.
2. Define exposure and absorbed dose.
Explain about Kerma in detail and derive a relationship between Kerma and
exposure.
Show that the roentgen to rad conversion factor for air is 0.876 under CPE.
II. Write notes on: (10 x 6 60)
1. Mass energy transfer and Mass energy absorption coefficients.
2. Photo neutrons.
3. Cyclotron produced isotopes.
4. Bragg-Gray cavity theory
5. Beta gamma coincidence counting.
6. Explain about the free air ionization chamber with a neat diagram.
7. Fricke dosimeter.
8. Define apparent activity, Reference Air Kerma Rate, Air Kerma Rate constant.
9. Chemical dosimeters in radiotherapy.
10. Theory and operation of Silicon Diode detectors.