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DOE OSTI · 22218170

Background modeling for the GERDA experiment

Becerici-Schmidt, N.
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Abstract

The neutrinoless double beta (0νββ) decay experiment GERDA at the LNGS of INFN has started physics data taking in November 2011. This paper presents an analysis aimed at understanding and modeling the observed background energy spectrum, which plays an essential role in searches for a rare signal like 0νββ decay. A very promising preliminary model has been obtained, with the systematic uncertainties still under study. Important information can be deduced from the model such as the expected background and its decomposition in the signal region. According to the model the main background contributions around Q{sub ββ} come from {sup 214}Bi, {sup 228}Th, {sup 42}K, {sup 60}Co and α emitting isotopes in the {sup 226}Ra decay chain, with a fraction depending on the assumed source positions.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICSALPHA DECAYBISMUTH 214COBALT 60COMPUTERIZED SIMULATIONDOUBLE BETA DECAYENERGY SPECTRAMASS NUMBERMULTIPARTICLE SPECTROMETERSPARTICLE IDENTIFICATIONPOTASSIUM 42RADIUM 226THORIUM 228

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Becerici-Schmidt, N.. 2013-08-08. Background modeling for the GERDA experiment. https://doi.org/10.1063/1.4818098

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