Energy resolution of a photon-counting silicon strip detector
2010 (English)In: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, ISSN 0168-9002, 156-162 p.Article in journal (Refereed) Published
A photon-counting silicon strip detector with two energy thresholds was investigated for spectral X-ray imaging in a mammography system. Preliminary studies already indicate clinical benefit of the detector, and the purpose of the present study is optimization with respect to energy resolution. Factors relevant for the energy response were measured, simulated, or gathered from previous studies, and used as input parameters to a cascaded detector model. Threshold scans over several X-ray spectra were used to calibrate threshold levels to energy, and to validate the model. The energy resolution of the detector assembly was assessed to range over ΔE/E=0.12–0.26 in the mammography region. Electronic noise dominated the peak broadening, followed by charge sharing between adjacent detector strips, and a channel-to-channel threshold spread. The energy resolution may be improved substantially if these effects are reduced to a minimum. Anti-coincidence logic mitigated double counting from charge sharing, but erased the energy resolution of all detected events, and optimization of the logic is desirable. Pile-up was found to be of minor importance at typical mammography rates.
Place, publisher, year, edition, pages
2010. 156-162 p.
Spectral X-ray imaging, Mammography; Silicon strip detector, Photon counting, Energy resolution, Cascaded detector model
Electrical Engineering, Electronic Engineering, Information Engineering Medical Laboratory and Measurements Technologies Other Engineering and Technologies not elsewhere specified Radiology, Nuclear Medicine and Medical Imaging
IdentifiersURN: urn:nbn:se:kth:diva-11636DOI: 10.1016/j.nima.2009.10.152ISI: 000274772800023ScopusID: 2-s2.0-77949279240OAI: oai:DiVA.org:kth-11636DiVA: diva2:278573
QC 201007142009-11-272009-11-272011-01-20Bibliographically approved