Difference between revisions of "Measurements and Calculations (Introduction to Radiochemistry)"
(→Background) |
(→Background) |
||
Line 8: | Line 8: | ||
==== Background ==== | ==== Background ==== | ||
− | 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> | + | Note down the values from the background counting you started the day before.<br> Counting number:<br> |
+ | <math>N_{bck}=\underline{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,}\mbox{counts}</math><br> Counting time:<br> | ||
+ | <math>t{bck}=\underline{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,}\mbox{sec}</math><br> Counting speed:<br> | ||
+ | <math>\frac{N_{bck}}{t_{bck}}=\underline{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,}\mbox{cps}</math> <br> Standard deviation:<br> | ||
+ | <math>\frac{\sqrt{N_{bck}}}{t_{bck}}=\underline{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,}\mbox{cps}</math><br> | ||
==== Counting Efficiency ==== | ==== Counting Efficiency ==== |
Revision as of 08:59, 3 July 2012
Return to Main
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 | |
1 | ||
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 | |||
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>:
|
|
|
|
Is there, in your opinion, to many single measurements outside of the given areas? Give a answer based on statistical normal distribution.