To Whom it may concern,

on behalf of the DarkSide Collaboration I would like to submit a request to give a contribution to TIPP 2014. I am aware the deadline is passed and understand this might be difficult. However, considering the new results from our group, please take this into consideration. In the following an abstract. In case you could allocate a slot for us I will identify a speaker.

Thank you for your attention Best regards Aldo Ianni for the DS collaboration

Abstract

DarkSide-50 (DS-50) at Gran Sasso underground laboratory, Italy, is a direct dark matter search experiment based on a TPC with liquid argon from underground sources. The DS-50 TPC, with 50 kg of active argon and a projected fiducial mass of >33 kg, is installed inside an active neutron veto based on a boron-loaded organic scintillator. The neutron veto is built inside a water cherenkov muon veto. DS-50 has been taking data since Nov 2013, collecting more than 2e7 events with atmospheric argon. This data represents an exposure to the largest background, beta decays of Ar-39, comparable to the full three-year run planned for DS-50 with underground argon. When analyzed with a threshold that would give a sensitivity in the full run of about 1e-45 cm^2 at a WIMP mass of 100 GeV/c^2, there is no Ar-39 background observed. The detector design and performance will be presented as well as results from the atmospheric argon run still in progress. Plans for the underground argon run and for a ton-scale detector within the same neutron veto vessel will be presented.

-------------------------------------------------------------------- Aldo Ianni Research Division, INFN Gran Sasso Laboratory S.S. 17bis 67010 Assergi (AQ) Italy

tel: +39-0862-437-482 fax:+39-0862-437-570 email: aldo.ianni@lngs.infn.it