Difference between revisions of "Measurements and Calculations (Introduction to Radiochemistry)"
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==== Assessment of the Results ==== | ==== Assessment of the Results ==== | ||
− | Write down the given measurements and calculate how many % of the countings that are outside of the intervals <N-S<sub>N</sub>,N+S<sub>N</sub> and <N-2S<sub>N</sub>,N+2S<sub>N</sub>>: | + | Write down the given measurements and calculate how many % of the countings that are outside of the intervals <N-S<sub>N</sub>,N+S<sub>N</sub> and <N-2S<sub>N</sub>,N+2S<sub>N</sub>>: |
+ | |||
+ | {| width="200" cellspacing="1" cellpadding="1" border="1" | ||
+ | |- | ||
+ | | <math>\overline{N}</math> | ||
+ | | <math>\sqrt{\overline{N}}</math> | ||
+ | | <math>N\pm S_{N}</math> | ||
+ | | <math>N\pm 2S_{N}</math> | ||
+ | |- | ||
+ | | | ||
+ | | | ||
+ | | | ||
+ | | | ||
+ | |} |
Revision as of 16:08, 2 July 2012
Which detector did you use?
Contents
Background
Note down the values from the background counting you started the day before.
Counting number Nbck= counts
Counting time tbck= sec
Counting speed = cps
Standard deviation = cps
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 | |
1 | ||
2 | ||
3 | ||
4 |
Twenty Measurements with Constant Distance from the Source
Do twenty measurements on 1 minute with the source in the same position. Calculate the standard deviation and complete the table:
Nr | Np | ||
1 | |||
2 | |||
3 | |||
4 | |||
5 | |||
6 | |||
7 | |||
8 | |||
9 | |||
10 | |||
11 | |||
12 | |||
13 | |||
14 | |||
15 | |||
16 | |||
17 | |||
18 | |||
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>: