Mainz 2012 – wissenschaftliches Programm
HK 24.7: Vortrag
Mittwoch, 21. März 2012, 15:45–16:00, RW 3
Measurement of neutron fluxes as a background for direct Dark Matter searches — •Valentin Kozlov — Karlsruher Institut für Technologie, Institut für Kernphysik, Postfach 3640, 76021 Karlsruhe
A very low interaction rate is expected for Dark Matter candidates, so-called weakly interacting massive particles (WIMP), scattering off a nucleus of a terrestrial detector. This emphasizes the importance of a detailed understanding of all potential backgrounds. Ambient and muon-induced neutrons constitute a prominent background component. Detailed studies carried out by the Edelweiss collaboration in this respect are presented. Edelweiss is a Ge-bolometer experiment searching for WIMPs and located in the underground laboratory Laboratoire Souterrain de Modane (LSM, France). The neutron background studies include dedicated calibrations with neutron sources, monitoring the neutron flux with 3He detectors and measurements with a neutron counter based on Gd-loaded liquid scintillator as well as corresponding MC simulations with full event topology. Studies of muon-induced neutrons are of particular interest and will be the main focus of the presentation. The impact of the neutron background on current Edelweiss data-taking as well as for next generation experiments such as EURECA will be discussed.
This work is supported by BMBF (Astroparticle Physics project 05A11VK2) and by the Helmholtz Alliance for Astroparticle Phyics HAP, by the French Agence Nationale pour la Recherche and the Russian Foundation for Basic Research (grant No. 07-02-00355-a).