Use Deadtime Correction
The deadtime correction can be disabled for use in certain unusual analytical situations. The program will type a warning to the log window during a quantitative analysis if the deadtime correction is disabled. Two deadtime correction options are available, the normal expression shown here :
Expression # 1
:
Where : i is the raw measured counts in cps
is the deadtime constant in seconds
I is the deadtime corrected counts in cps
and a high precision expression (Willis, 1993) for use with very high count rates (> 50K cps) shown here :
Expression #2
:
This high precision expression differs from the normal expression only at very high count rates. The following table shows the difference between the two expressions at various count rates :
|
CPS |
#1 @ 1 us |
#2 @ 1 us |
#1 @ 2 us |
#2 @ 2 us |
#1 @ 4 us |
#2 @ 4 us |
|
5K |
.995 |
.9950125 |
.99 |
.99005 |
.98 |
.9802 |
|
10K |
.99 |
.99005 |
.98 |
.9802 |
.96 |
.9608 |
|
50K |
.95 |
.95125 |
.9 |
.905 |
.8 |
.82 |
|
100K |
.9 |
.905 |
.8 |
.82 |
.6 |
.68 |
|
200K |
.8 |
.82 |
.6 |
.68 |
.2 |
.52 |
|
400K |
.6 |
.68 |
.2 |
.52 |
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