Difference between revisions of "Measurements and Calculations (Introduction to Radiochemistry)"
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==== Background ==== | ==== Background ==== | ||
− | Note down the values from the background counting you started the day before.<br> Counting number | + | Note down the values from the background counting you started the day before.<br> Counting number <math>N_{bck}=\underline{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,}\mbox{Counts}</math><br> Counting time <math>t{bck}=\underline{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,}\mbox{sec}</math><br> Counting speed <math>\frac{N_{bck}}{t_{bck}}=\underline{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,}\mbox{cps}</math> <br> Standard deviation <math>\frac{\sqrt{N_{bck}}}{t_{bck}}=\underline{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,}\mbox{cps}</math><br> |
==== Counting Efficiency ==== | ==== Counting Efficiency ==== |
Revision as of 08:57, 3 July 2012
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Which detector did you use?
Contents
Background
Note down the values from the background counting you started the day before.
Counting number
Counting time
Counting speed
Standard deviation
Counting Efficiency
Do a one minute count on every shelf. Use these measurements to calculate the counting-efficiency of the GM-detector in %, for 234mPa. The activity of the sample can be calculated from the amount of UO3 used.
Counting number for each shelf (CPM) | Counting Efficency | |
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2 | ||
3 | ||
4 |
Twenty Measurements with Constant Distance from the Source
Do twenty measurements lasting for one minute with the source in the same position. Calculate the standard deviation and complete the table:
Nr | |||
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2 | |||
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4 | |||
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8 | |||
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19 | |||
20 | |||
SUM: | SUM: |
Mean value of the counting numbers
The squere of the mean value
Standard deviation
Discuss the results from and ?
Assessment of the Results
Write down the given measurements and calculate how many % of the countings that are outside of the intervals <N-SN,N+SN and <N-2SN,N+2SN>:
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Is there, in your opinion, to many single measurements outside of the given areas? Give a answer based on statistical normal distribution.