PerkinElmer QuantaSmart 1694267

CALCULATIONS
PerkinElmer Life and Analytical Sciences 185
Half-life Correction
The process of half-life correction recalculates sample CPM or DPM and accounts
for the half-life decay of the sample nuclide. This calculation is performed as
follows:
The half-life correction is performed after the background correction.
IPA Background
The IPA background may be subtracted from all samples. The background value is
established as the mean of the first five background values collected via the SNC
(Self-Normalization and Calibration) protocol.
LCR (Low Count Reject)
Low Count Reject (LCR) is a means of rejecting samples if the sample nuclide
activity doesn’t meet a minimum specified criterion. Samples are rejected and
flagged if they do not reach the specified count level within the first 30 seconds of
the sample count.
LUM (% Luminescence)
This value represents the % luminescence of a sample and is calculated as
follows:
datecurrentthetodatereferencethefromhours,inintervaltimet
scale)clogarithminaturalof(base2.71828e
hoursinde,radionuclitheoflife-halftheT(HL)
nuclidetheofactivitystartingtheActivity
activityremainingcurrenttheActivity
:where
e x ActivityActivity
initial
current
hl)-0.693t/T(
initialcurrent
=
=
=
=
=
=
∑
=
5
1
iIPA
BKG BKG
100 x
events ecoincidenc true
events ecoincidenc chance
LUM =