1. APHY398C 6/4/2016 1 Dosimetry   Quantifying the incidence of various biological changes as a function of the radiation dose.   Exposure Ratio of total charge produced by photons in air to the mass of air Unit: Roentgen (R) where 1 R = 2.58 x 10 -4 C/kg

2. APHY398C 6/4/2016 2 Dosimetry   Dose The energy absorbed per unit mass from any kind of ionizing radiation in any target. Unit: Gray (Gy) where 1 Gy = 1 J/kg = 100 rad   Dose Equivalent Allows for different effects by different radiation H = QD Unit: Sievert (Sv) where 1 Sv = 100 rem

3. APHY398C 6/4/2016 3 Dosimetry   Measuring the dose Bragg-Gray principle   X-rays and Gamma rays

4. APHY398C 6/4/2016 4 Dosimetry   Neutrons Calibrate a C-CO 2 chamber to neutron energies Must account for any gamma rays present Q ~ 3 for E n 10 keV

5. APHY398C 6/4/2016 5 Dosimetry   Calculations Alpha and Beta emitters Gamma ray point source

6. APHY398C 6/4/2016 6 Dosimetry Neutrons – fast and slow Fluence – the number of neutrons per unit area that cross a plane perpendicular to the beam ~ N/(4πd 2 ) Conversion from fluence to dose