Critical revision of the ZEPLIN-I sensitivity to WIMP interactions

Abstract

The ZEPLIN collaboration has recently published its first result presenting a maximum sensitivity of $1.1\times 10^{-6}$ picobarn for a WIMP mass of $\approx$ 60 GeV. The analysis is based on a discrimination method using the different time distribution of scintillation light generated in electron recoil and nuclear recoil interactions. We show that the methodology followed both for the calibration of the ZEPLIN-I detector response and for the estimation of the discrimination power is not reliable enough to claim any background discrimination at the present stage. The ZEPLIN-I sensitivity appears then to be in the order of 10${}^{-3}$ picobarn, three orders of magnitude above the claimed 1.1 10${}^{-6}$ picobarn.

arXiv comment8 pages, 4 figures, minor corrections, two references updated, final version accepted in Physics Letters B

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Cited by in corpus (4)

• Technical aspects and dark matter searches
• Direct Search for Dark Matter - Striking the Balance - and the Future
• Status of direct searches for WIMP dark matter
• Reply to: Critical revision of the ZEPLIN-I sensitivity to WIMP interactions