title: Analytic model of energy-absorption response functions in compound X-ray detector materials.
abstract: The absorbed energy distribution (AED) in X-ray imaging detectors is an important factor that affects both energy resolution and image quality through the Swank factor and detective quantum efficiency. In the diagnostic energy range (20-140 keV), escape of characteristic photons following photoelectric absorption and Compton scatter photons are primary sources of absorbed-energy dispersion in X-ray detectors. In this paper, we describe the development of an analytic model of the AED in compound X-ray detector materials, based on the cascaded-systems approach, that includes the effects of escape and reabsorption of characteristic and Compton-scatter photons. We derive analytic expressions for both semi-infinite slab and pixel geometries and validate our approach by Monte Carlo simulations. The analytic model provides the energy-dependent X-ray response function of arbitrary compound materials without time-consuming Monte Carlo simulations. We believe this model will be useful for correcting spectral distortion artifacts commonly observed in photon-counting applications and optimal design and development of novel X-ray detectors.
authors.forename: Seungman
authors.initials: S
authors.lastname: Yun
authors.forename: Ho Kyung
authors.initials: HK
authors.lastname: Kim
authors.forename: Hanbean
authors.initials: H
authors.lastname: Youn
authors.forename: Jesse
authors.initials: J
authors.lastname: Tanguay
authors.forename: Ian A
authors.initials: IA
authors.lastname: Cunningham
mesh_terms: D000042:Absorption; D008962:Models, Theoretical; D009010:Monte Carlo Method; D017785:Photons; D011859:Radiography / Q000295:instrumentation*; D015203:Reproducibility of Results; D012542:Scattering, Radiation; D014965:X-Rays