CdZnTe background measurement at balloon altitudes with an active BGO shield

Peter Forbes Bloser; Jonathan E. Grindlay; Tomohiko Narita; Fiona A. Harrison

doi:10.1117/12.330275

10 November 1998 CdZnTe background measurement at balloon altitudes with an active BGO shield

Peter Forbes Bloser, Jonathan E. Grindlay, Tomohiko Narita, Fiona A. Harrison

Proceedings Volume 3445, EUV, X-Ray, and Gamma-Ray Instrumentation for Astronomy IX; (1998) https://doi.org/10.1117/12.330275
Event: SPIE's International Symposium on Optical Science, Engineering, and Instrumentation, 1998, San Diego, CA, United States

Abstract

We report results of an experiment conducted in May 1997 to measure CdZnTe background and background reduction schemes in space flight conditions similar to those of proposed hard x-ray astrophysics missions. A 1 cm² CdZnTe detector was placed adjacent to a thick BGO anticoincidence shield and flown piggy backed onto the EXITE2 scientific balloon payload. The planar shield was designed to veto background counts produced by local gamma-ray production in passive material and neutron interactions in the detector. The CdZnTe and BGO were partially surrounded by a Pb-Sn-Cu shield to approximate the grammage of an x-ray collimator, although the field of view was still approximately 2 (pi) sr. At an altitude of 127000 feet we find a reduction in background by a factor of 6 at 100 keV. The non-vetoed background is 9 by 10⁴ cts cm^-2s^-1 at 100 keV, about a factor of 2 higher than that of the collimated EXITE2 phoswich detector. We compare our recorded spectrum with that expected from simulations using GEANT and find agreement within a factor of 2 between 30 and 300 keV. We also compare our results with those of previous experiments using passive lead and active NaI shields, and discus possible active shielding schemes in future astronomy mission employing large arrays of CdZnTe detectors.

Citation Download Citation

Peter Forbes Bloser, Jonathan E. Grindlay, Tomohiko Narita, and Fiona A. Harrison "CdZnTe background measurement at balloon altitudes with an active BGO shield", Proc. SPIE 3445, EUV, X-Ray, and Gamma-Ray Instrumentation for Astronomy IX, (10 November 1998); https://doi.org/10.1117/12.330275

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

Includes PDF, HTML & Video, when available