Orateur
Dr
Marco Selvi
(INFN - Bologna)
Description
Presented by M. Selvi on behalf of the XENON1T collaboration.
Within the XENON program, we are operating a double-phase TPCs using liquid xenon (LXe) as target material. The current phase, XENON100 installed in the LNGS, is in science mode since the beginning of 2010, with a sensitivity goal of 2 x 10-45 cm2.
For the next step, we propose to build a detector with a total mass of 2.4 tons of LXe (1.1 fiducial): XENON1T. The goal is to reduce the background by two orders of magnitude with respect to XENON100, reaching a sensitivity of about 5 x 10-47 cm2.
Therefore it is crucial to reduce the external backgrounds: gammas and neutrons from the ambient radioactivity and the most dangerous muon-induced neutrons.
A careful study of the shield and muon veto needed by the experiment has been carried on with a full Geant4 MC simulation.
Two possibilities for the experimental site are considered: LNGS or LSM.
To shield the experiment at LNGS a water tank of 10 m diameter and 10 m height will be necessary; moreover the water will be instrumented with PMTs to act as a Cherenkov muon veto.
At LSM (where the muon flux is reduced by about a factor 50 with respect to LNGS , because of its larger rock overburden) a similar result could be achieved with a conventional passive shield and a plastic scintillator muon veto.
The results obtained for the two site options are presented in this work.
Author
Dr
Marco Selvi
(INFN - Bologna)
