Which detector has the best energy resolution?
Which detector has the best energy resolution?
Planar detectors usually achieve the best energy resolution, because of their low capacitance; they are preferred for detailed spectroscopy, such as the analysis of the complex low-energy gamma-ray and x-ray spectra of uranium and plutonium.
How do you find the resolution of a detector?
Re is obtained from the peak full width at half of the maximum height (FWHM) using the following equation: Re = FWHM / E (%), where E is the related energy of the peak. Re is better (i.e., its % value is lower) for higher energies.
What is gamma resolution?
Resolution figures are given with reference to specified gamma ray energies. Resolution can be expressed in absolute (i.e., eV or MeV) or relative terms. For example, a sodium iodide (NaI) detector may have a FWHM of 9.15 keV at 122 keV, and 82.75 keV at 662 keV. These resolution values are expressed in absolute terms.
How do you determine gamma?
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 energy resolution of a gamma camera?
The energy resolution for gamma cameras is typically in the 9% to 11% range for 99mTc. Figure 14-4 shows a typical gamma camera spectrum for 99mTc with the pulse-height analyzer (PHA) window set to 130 to 150 keV. This corresponds to approximately a 15% energy window, which is a common setting for clinical studies.
What is FWHM in resolution?
The full width at half maximum (FWHM) is the width of a line shape at half of its maximum amplitude, as shown below: A closely related quantity is the half width at half maximum (HWHM) or the Resolving Resolution and it is half of the FWHM.
How does a gamma detector work?
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 gamma ray the size of?
A gamma ray is electromagnetic radiation of the shortest wavelength and highest energy. Gamma-ray radiation has wavelengths generally smaller than a few tenths of an angstrom (10−10 meter), and gamma-ray photons have energies greater than tens of thousands of electron volts.
