PerkinElmer QuantaSmart 1694267, Reference Manual

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GLOSSARY
PerkinElmer Life and Analytical Sciences 193
Half-Life
Half-Life is the time in which one-half the atoms of a radioactive substance
disintegrate to another nuclear form.
IPA (Instrument Performance Assessment)
IPA is a process by which a TriCarb instrument measures background, counting
efficiency, sensitivity (Figure-of-Merit) and the reproducibility of sample counting
(Chi-Square test).
Isotope
This refers to atoms of the same element that have the same atomic number with
different atomic weights.
keV (kiloelectron Volt)
One thousand electron volts. This is the unit used to express the energy
associated with radioactive decay.
Library
In the QuantaSmart program, a library is a repository of data regarding sample
nuclides or standards.
Luminescence
This is a general term applied to the emission of light that cannot be attributed to
the radioactivity of the sample. It is typically due to a chemical reaction between
the sample and the emulsifier (detergent) containing cocktails. Luminescence is
most often caused by alkaline pH and peroxides in the sample.
Normalization
Normalization is a process used to establish a lower limit of measurement for
quench.
Nuclide
This is a general term applicable to all isotopes, stable and radioactive, of all
elements. Frequently, the term “isotope” is erroneously used to mean nuclide.
Photomultiplier Tube (PMT)
A PMT is a device capable of converting low levels of light into electrical energy
(photoelectrons). Photoelectrons generated in a PMT are multiplied to facilitate
their detection.
Photon
In the quantum theory of electromagnetic radiation, light is emitted in discrete
units of energy called photons.