ABR ABR Radiation Dosimetry

Question 1

What is the SI unit of absorbed dose used in radiation dosimetry?

Accepted Answer

Gray (Gy)

Answer

Sievert (Sv)

Answer

Becquerel (Bq)

Answer

Roentgen (R)

Question 2

Which type of ionization chamber is the recommended reference dosimeter for photon beam calibration per AAPM TG-51?

Accepted Answer

Farmer-type cylindrical chamber

Answer

Parallel-plate chamber

Answer

Thimble chamber

Answer

Diamond detector

Question 3

In TG-51 dosimetry protocol, what reference depth is used for photon beam calibration?

Accepted Answer

10 cm

Answer

5 cm

Answer

dmax

Answer

15 cm

Question 4

What is the purpose of the kQ factor in the TG-51 calibration protocol?

Accepted Answer

Corrects for beam quality differences from the calibration standard

Answer

Corrects for temperature and pressure

Answer

Accounts for chamber polarity effect

Answer

Corrects for ion recombination

Question 5

Which dosimetry formalism does AAPM TG-51 replace for clinical photon and electron beam calibration in the US?

Accepted Answer

TG-21

Answer

TG-43

Answer

TG-61

Answer

TG-25

Question 6

What correction factor accounts for the incomplete collection of ions in a dosimetry chamber?

Accepted Answer

Ion recombination correction (Pion)

Answer

Polarity correction (Ppol)

Answer

Perturbation correction (Pfl)

Answer

Wall correction (Pwall)