Journal of Radioanalytical and Nuclear Chemistry

, Volume 286, Issue 2, pp 477–482 | Cite as

Pulse shape analysis to reduce the background of BEGe detectors

  • Raquel González de Orduña
  • Mikael Hult
  • Erica Andreotti
  • Dušan Budjáš
  • Stefan Schönert
  • Marcin Misiaszek
Article

Abstract

A simple technique for pulse shape discrimination in HPGe-detectors of the so-called BEGe type, based on just one parameter obtained from one signal read out, is presented here. This technique allows discriminating between pulses generated when the deposited energy is located within a small region of about 1 mm3 from the pulses generated when the energy is deposited at different locations several mm or cm apart. Two possible applications using this technique are: (i) experiments that look for neutrinoless double β decay in 76Ge, such as GERDA; (ii) γ spectrometry measurements where the Compton continuum can be reduced and the efficiency for cascading γ-rays can remain high. With this active background reduction technique a Compton suppression factor of about 3 was obtained. The detector response may be influenced by the detector size. The detector used for this study had a diameter of 6 cm, a thickness of 2.6 cm and a relative efficiency of 19%. The results obtained with this detector were consistent with the results obtained by Budjáš et al. [J Instrum 4:10, 2009] with a 50% relative efficiency BEGe detector.

Keywords

Pulse shape discrimination BEGe detector Background reduction 

Abbreviations

PSA

Pulse shape analysis

PSD

Pulse shape discrimination

SSE

Single site event

MSE

Multiple site event

FEP

Full energy peak

DEP

Double escape peak

SEP

Single escape peak

CC

Compton continuum

BEGe

Broad energy germanium

GERDA

GERmanium detector array

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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2010

Authors and Affiliations

  • Raquel González de Orduña
    • 1
  • Mikael Hult
    • 1
  • Erica Andreotti
    • 1
  • Dušan Budjáš
    • 2
  • Stefan Schönert
    • 2
  • Marcin Misiaszek
    • 3
  1. 1.European Commission, Joint Research CentreInstitute for Reference Materials and MeasurementsGeelBelgium
  2. 2.Max-Planck-Institut für KernphysikHeidelbergGermany
  3. 3.M.Smoluchowski Institute of PhysicsJagiellonian UniversityKrakowPoland

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