## How do you calculate efficiency of a detector?

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). For a cylindrical container l = H and for a complex-shaped container l = H – h.

### What is the efficiency of a radiation detector?

For a given detector, efficiency values depend on the type and energy of the incident radiation. For incident charged particles such as alpha particles or beta particles, many detectors have a total efficiency that is close to 100 percent.

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 gamma detection?

Like X-ray detection, gamma-ray detection is done photon-by-photon. Gamma rays are detected by observing the effects they have on matter. A gamma ray can collide with an electron and bounce off it like a billiard ball (Compton scatter) or it can push an electron to a higher energy level (photoelectric ionization).

## 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).

### Does the efficiency of a gamma detector increase or decrease as the energy of the ray increases?

The obtained results have been displayed as a function of gamma ray energy in Figure 4. The results are displayed in Figure 5 for 5 different distances and 6 different energies. It can be seen from this figure that the detection efficiency has decreased exponentially with the increasing distance from detector face.

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).

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 a good detector of gamma rays?

Silicon detectors are most heavily used in charged-particle spectroscopy and are also used for Compton- recoil spectroscopy of high-energy gamma rays. Other solid-state detection media besides germanium and silicon have been applied to gamma-ray spectroscopy.

### What detector detects gamma rays?

The thallium-activated sodium iodide detector, or NaI(Tl) detector, responds to the gamma ray by producing a small flash of light, or a scintillation. The scintillation occurs when scintillator electrons, excited by the energy of the photon, return to their ground state.

What is Nal scintillation detector?

What is detdetection efficiency of gamma detector?

Detection efficiency is one of the main parameter in detection system besides many other different parameters of the detector. The absolute efficiency of the gamma detector system will be used at Turkish Accelerator and Radiation Laboratory at Ankara (TARLA) is simulated using MCNPX code (version 2.4.0).

## What is the relative efficiency of a germanium detector?

Often, Germanium detector efficiencies are expressed as relative efficiencies. This is the efficiency relative to a 60 Co source (using the 1332 keV peak) measured with a 3″x 3″ NaI (Tl) detector at a distance of 25 cm from the detector.

### What is meant by relative efficiency of detector?

Relative Efficiency: Efficiency of one detector relative to another; commonly that of a germanium detector relative to a 3 in. diameter by 3 in. long NaI crystal, each at 25 cm from a point source, and specified at 1.33 MeV only.