Comparison of energy resolution spectra of CdTe TIMEPIX detector working in photon counting and time-over-threshold mode

DOI: 10.1109/NSSMIC.2013.6829825

Authors: David Krapohl (Mid Sweden University) , Chrsiter Frojdh (Mid Sweden University) , Goran Thungstrom (Mid Sweden University) , Erik Frojdh (CERN) , Eva Gimenez-Navarro (Diamond Light Source) , Heribert Wilhelm (Diamond Light Source) , Nicola Tartoni (Diamond Light Source) , Dzmitry Maneuski (University of Glasgow) , Val O'Shea (University of Glasgow) , Kennenth Wraight (University of Glasgow)
Co-authored by industrial partner: No

Type: Conference Paper
Conference: Nuclear Science Symposium and Medical Imaging Conference
Peer Reviewed: Yes

State: Published (Approved)
Published: November 2013

Abstract: Hybrid pixel detectors like the Medipix and TIMEPIX developed by the Medipix collaboration combined with high-z materials are of growing interest. In particular the TIMEPIX detector can be operated in photon counting mode and time-over-threshold mode (ToT) to obtain spectral information. Previous studies showed that 110ìm pixel sizes obtain a better energy resolution than 55ìm pixel sizes. Furthermore, threshold scans obtained a better spectral resolution than operation in ToT mode. In this work the influence of noise sources in different measurement approaches on the spectral response of a TIMEPIX chip bump-bonded to CdTe sensor are presented. Two 1mm thick CdTe sensors with pixel sizes of 55ìm and 110 ìm, bump-bonded to a TIMEPIX readout chip, were evaluated at the Diamond Light Source synchrotron. A finely collimated, perpendicular pencil beam with x-ray energies of 25 keV and 79 keV was used to investigate single pixels. A small area of 10x10 pixels was investigated in ToT-mode and compared to a threshold scan of the same pixels on both detectors. The measurements are compared to an analytical SPICE/Python simulation

Subject Areas: Physics, Engineering


Instruments: I15-Extreme Conditions

Added On: 30/06/2014 12:08

Documents:
Manuscript_R05-10.pdf

Discipline Tags:

Detectors Physics Engineering & Technology

Technical Tags:

Diffraction