Test apparatus to monitor time-domain signals from semiconductor-detector pixel arrays

Kyle Haston; H. Bradford Barber; Lars R. Furenlid; Esen Salçin; Vaibhav Bora

doi:10.1117/12.898365

23 September 2011 Test apparatus to monitor time-domain signals from semiconductor-detector pixel arrays

Kyle Haston, H. Bradford Barber, Lars R. Furenlid, Esen Salçin, Vaibhav Bora

Author Affiliations +

Proceedings Volume 8143, Medical Applications of Radiation Detectors; 81430P (2011) https://doi.org/10.1117/12.898365
Event: SPIE Optical Engineering + Applications, 2011, San Diego, California, United States

Abstract

Pixellated semiconductor detectors, such as CdZnTe, CdTe, or TlBr, are used for gamma-ray imaging in medicine and astronomy. Data analysis for these detectors typically estimates the position (x, y, z) and energy (E) of each interacting gamma ray from a set of detector signals {S_i} corresponding to completed charge transport on the hit pixel and any of its neighbors that take part in charge sharing, plus the cathode. However, it is clear from an analysis of signal induction, that there are transient signal on all pixel electrodes during the charge transport and, when there is charge trapping, small negative residual signals on all electrodes. If we wish to optimally obtain the event parameters, we should take all these signals into account. We wish to estimate x,y,z and E from the set of all electrode signals, {S_i(t)}, including time dependence, using maximum-likelihood techniques[1]. To do this, we need to determine the probability of the electrode signals, given the event parameters {x, y, z, E}, i.e. Pr( {S_i(t)} | {x, y, z, E} ). Thus we need to map the detector response of all pixels, {S_i(t)}, for a large number of events with known x,y,z and E.In this paper we demonstrate the existence of the transient signals and residual signals and determine their magnitudes. They are typically 50-100 times smaller than the hit-pixel signals. We then describe development of an apparatus to measure the response of a 16-pixel semiconductor detector and show some preliminary results. We also discuss techniques for measuring the event parameters for individual gamma-ray interactions, a requirement for determining Pr( {S_i(t)} | {x, y, z, E}).

Citation Download Citation

Kyle Haston, H. Bradford Barber, Lars R. Furenlid, Esen Salçin, and Vaibhav Bora "Test apparatus to monitor time-domain signals from semiconductor-detector pixel arrays", Proc. SPIE 8143, Medical Applications of Radiation Detectors, 81430P (23 September 2011); https://doi.org/10.1117/12.898365

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

;

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE