Ústav technické a experimentální fyziky Institute of Experimental and Applied Physics

Energy-sensitive X-ray radiography and charge sharing effect in pixelated detector

NázevTitle
Energy-sensitive X-ray radiography and charge sharing effect in pixelated detectorEnergy-sensitive X-ray radiography and charge sharing effect in pixelated detector
Druh výsledkuResult type
Článek v časopiseJournal article
AutořiAuthors
J. Jakůbek
DOIDOI
10.1016/j.nima.2009.03.148
Časopis / citaceJournal / citation
Nuclear Instruments and Methods in Physics Research, Section A, Accelerators, Spectrometers, Detectors and Associated Equipment. 2009, 607(1), 192-195. ISSN 0168-9002.
RokYear
2009
JazykLanguage
eng
WoSWoS
000268987900055
ScopusScopus
2-s2.0-67649222284
RIVRIV
RIV/68407700:21670/09:00165388!RIV10-MSM-21670___
ProjektProject
Příprava, modifikace a charakterizace materiálů energetickým zářenímPreparation, Modification and Characterization of Materials by Energetic Radiation; Využití radionuklidů a ionizujícího zářeníApplication of radionuclides and ionising radiation

AbstraktAbstract

The possibility of per pixel energy measurement presents a substantial advantage for X-ray radiography with polychromatic X-ray sources allowing material identification via analysis of transmission energy spectra. The energy resolution of the pixelated planar detector is, however, influenced by charge sharing. The ionization charge generated by the particle (X-ray photon) can be collected by several pixels, forming a cluster. If the fraction of the charge collected by a particular pixel drops below the energy threshold it is not counted and therefore it is lost. This fact, together with the presence of noise, limits the energy resolution of the device. A simplified model of the charge sharing effect is studied in this work and compared with experimental data. The application of a energy-calibrated TimePix detector in the field of energy-sensitive X-ray radiography enables the recognition of soft biological materials (fat and muscle tissue) which is presented here.

The possibility of per pixel energy measurement presents a substantial advantage for X-ray radiography with polychromatic X-ray sources allowing material identification via analysis of transmission energy spectra. The energy resolution of the pixelated planar detector is, however, influenced by charge sharing. The ionization charge generated by the particle (X-ray photon) can be collected by several pixels, forming a cluster. If the fraction of the charge collected by a particular pixel drops below the energy threshold it is not counted and therefore it is lost. This fact, together with the presence of noise, limits the energy resolution of the device. A simplified model of the charge sharing effect is studied in this work and compared with experimental data. The application of a energy-calibrated TimePix detector in the field of energy-sensitive X-ray radiography enables the recognition of soft biological materials (fat and muscle tissue) which is presented here.