How do you calculate intrinsic efficiency?
The intrinsic efficiency relates the counts in the spectrum to the number of gamma ray photons incident on the detector. Intrinsic efficiency is defined as: Intrinsic efficiency = Absolute efficiency ´ (4p/W) where W is the solid angle of the detector seen from the actual source position.
What is intrinsic efficiency?
Intrinsic efficiency is the ratio of the number of photons detected to the number of photons incident on the detector surface. Absolute and intrinsic efficiencies can be expressed as the full-energy peak efficiency which takes into consideration only the photons which result in counts in the full-energy peaks.
What is the intrinsic peak efficiency?
The intrinsic peak efficiency of the HPGe detector is the ratio of the counts of the HPGe detector to the number of monoenergetic photons irradiating it. Thus, the intrinsic efficiency of the detector does not vary with the source-to-detector distance, without the effect of the solid angle.
What is the efficiency of NaI TL scintillator?
The scintillation efficiency of a NaI(Tl) crystal to electrons in the energy range up to 70 keV has been deduced from the photon-excitation efficiency recently measured by the author. The efficiency curve has a peak at 7.8 keV and shows the highest values in the results ever reported in the region below 25 keV.
What is absolute efficiency?
Absolute efficiency is the ratio of the number of counts produced by the detector to the number of γ-rays emitted by the source into all directions. This efficiency depends on detector properties, sample properties and the relative sample-detector position.
How do you calculate radiation efficiency?
the efficiency of the detector for radiation from the sample must be calculated using formula ε(E) = ω ε0(E), finding the value of the coefficient ω for the relation (2).
What is scintillation in chemistry?
Scintillation is a flash of light produced in a transparent material by the passage of a particle (an electron, an alpha particle, an ion, or a high-energy photon).
What is geometric efficiency?
Geometric efficiency is defined as the number of radiation quanta (particles or photons) incident on the detector in a given interval divided by the number emitted by the radiation source in the same interval.
What is resolution of NaI detector?
2.2. Following were the specifications of the NaI(Tl) system: the resolution (FWHM) at 1.33 MeV 60Co was 60 keV, and the relative efficiency at 1.33 MeV 60Co was 7.5%. The detector was placed in the center of a two-layered chamber fabricated from stainless steel (10-mm thickness) and lead (30-mm thickness).
Why is thallium used in NaI detectors?
The doping of the NaI crystal with thallium improves the scintillation efficiency by improving the light emission due to the improved recombination by light emission of electrons and holes at the dopant site.
What is NaI TI detector?
A NaI(Tl) scintillation counter is a radiation detector which uses the effect known as scintillation. Scintillation, which occurs in the NaI(Tl) crystal, is a flash of light produced in a transparent material by the passage of a particle (an electron, an alpha particle, an ion, or a high-energy photon).