Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Response of large area avalanche photodiodes to low energy X-rays

Published

Author(s)

Thomas R. Gentile, Uwe Arp, M J. Bales, R Farrell

Abstract

For an experiment to study neutron radiative beta-decay, we operated large area avalanche photodiodes (APDs) at liquid nitrogen temperature to detect X-rays with energies between 0.2 keV and 15 keV. Whereas there are numerous reports of X-ray spectrometry using APDs at energies above 1 keV, operation at liquid nitrogen temperature allowed us to reach a nominal threshold of 0.1 keV. However, due to the short penetration depth of X-rays below 1 keV, the pulse height spectrum of the APD become complex. We studied the response using monochromatic X-ray beams and employed phenomenological fits of the pulse height spectrum to model the measurement of a continuum spectrum from a synchrotron. In addition the measured pulse height spectrum was modelled using a profile for the variation in efficiency of collection of photoelectrons with depth into the APD. The best results are obtained with the collection efficiency model.
Citation
Review of Scientific Instruments

Keywords

avalanche photodiodes, beta-decay, X-ray

Citation

, T. , Arp, U. , Bales, M. and Farrell, R. (2012), Response of large area avalanche photodiodes to low energy X-rays, Review of Scientific Instruments, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=910652 (Accessed June 13, 2024)

Issues

If you have any questions about this publication or are having problems accessing it, please contact reflib@nist.gov.

Created April 30, 2012, Updated February 19, 2017