Dose Calculations and 137Cs Shot Log

From New IAC Wiki
Jump to navigation Jump to search

Source Calibration and Dose Rate Data

Date Initial Source Strength (Ci) Current Source Strength (Ci) Distance to Faceplate (cm) Exposure Rate (Roentgen/hr)°
6/27/17 20 9.3 30.5 17.691
9/11/17 20 9.3 30.5 17.606

°Calculated by TSO using [math]\dot R = \frac {\Gamma A }{ D^2} [/math] where [math]\boldsymbol{\Gamma} = 3.3 \frac {(cm^2)(R)}{(mCi)(hr)} = .35 \frac {(m^2)(R)}{(Ci)(hr)} [/math] , [math]\mathbf{A} = 9.3 Ci [/math] , [math]\mathbf{D}=(\text{Distance to faceplate} + 11.2cm) [/math]

There is an adjustment distance of 11.2cm which accounts for the distance from the faceplate to the [math] ^{137}Cs[/math] source

Total exposures are calculated by [math]\int\limits_{t_0}^{t_f}\dot R\ dt [/math]

137Cs Shot Log

Dot OSLs

Date Run Number Run Time (s) Distance to Faceplate Number of OSLs in Stack Exposure Rate (R/hr) Total Exposed Dose (mR)
9/8/17 1 5660 30cm 11 18.7188 30148.8
9/8/17 1 5660 30cm 11 18.7188 30148.8
9/26/17 2 4500 30cm 11 18.7188 23398.6
9/26/17 2 4500 30cm 11 18.7188 23398.6

In these calculations, [math]\Gamma = 0.35 \frac {(m^2)(R)}{(Ci)(hr)} [/math]

Nanodot OSL Calibration and Quality Control

Calibration OSLs

Landauer Dosed OSLs

OSL # Listed Dose (mRad) Measured Dose (mRad) Average Dose (mRad)
DN08276339J Unexposed 71.19332 \
DN08276683L Unexposed 70.39211 72.10899
DN08258554P Unexposed 74.74154 /
DN10806640H 500 687.3246 \
DN10608908Z 500 681.0294 683.2422333
DN10806620J 500 681.3727 /
DN105057582 3000 3563.558 \
DN104085766 3000 3522.352 3567.258333
DN10608909X 3000 3615.865 /
DN108066085 50000 55966.55 \
DN103091798 50000 55420.36 55622.12
DN104086665 50000 55479.45 /
DN10606601L 100000 111610.5 \
DN106066095 100000 114271.2 114191.3333
DN10712163M 100000 116692.3 /

137Cs Calibration OSLs

10/24/27

Run for 82.9638 minutes for 25R

Run for 248.891 minutes for 75R

Run Time (s) Distance to Faceplate (cm) OSL # Total Exposed Dose (mR) Initial Dose (mRad) Measured Dose (mRad) Average Dose (mRad)
4977.83 30 DN08252102C - 7.210899 - -
4977.83 30 -DN08229824R - 9.84345 - -
4977.83 30 DN08241536W - 9.042238 - -

QC OSLs

OSL # Listed Dose (mRad) Measured Dose (mRad) Average Dose (mRad)
DN08264870R Unexposed 69.36198 \
DN082701640 Unexposed 77.25963 74.74153667
DN08269802P Unexposed 77.603 /
DN10712168C 1000 1235.238 \
DN10309170Q 1000 1223.106 1226.119667
DN102095379 1000 1220.015 /

Linear Fit

This fit was calculated using only the OSLs provided by Landauer for calibrating the OSL reader. [math] {\chi}^2 = 359.191[/math] [math] \text{# of Degrees of Freedom} = 13[/math]














Nanodot OSLS

Run 1, 10/12/17

Run Time (s) Distance to Faceplate (cm) Number of OSLs Total Exposed Dose (mR)
284.04 30.5cm 3 1476.92
OSL # Listed Dose (mRad) Measured Dose (mRad) Average Dose (mRad)
DN08252102C Unexposed 1161.413 \
DN08241536W Unexposed 1064.58 1148.9367
DN08229824R Unexposed 1220.817 /

Run 2, 10/23/17

Run Time (s) Distance to Faceplate (cm) Number of OSLs Total Exposed Dose (mR)
114.187 20 3 1000
OSL # Initial Dose (mRad) Measured Dose (mRad) Average Dose (mRad)
DN07916645R 64.3258 - \
DN08225747P 67.18726 - -
DN07924836M 66.72943 - /

Run 3, 10/23/17

Run Time (s) Distance to Faceplate (cm) Number of OSLs Total Exposed Dose (mR)
153.75 40 3 500
OSL # Initial Dose (mRad) Measured Dose (mRad) Average Dose (mRad)
DN08229607R 66.84389 - \
DN082562050 70.04873 - -
DN07923435X 67.6451 - /

Run 4

Run Time (s) Distance to Faceplate (cm) Number of OSLs Total Exposed Dose (mR)
- - -
OSL # Initial Dose (mRad) Measured Dose (mRad) Average Dose (mRad)
- - \
- - -
- - /

Reproducibility with 137Cs