Speaker
Description
The DarkSide program aims at detecting weakly interacting particle dark matter using dual-phase Liquid Argon Time Projection Chambers (LAr TPC) of increasing sensitivity. One of the distinctive features of the program is the use of underground argon with significantly lower 39Ar when compared with atmospheric argon.
The first detector of the program, DarkSide-50 (DS-50) is running at LNGS since 2013. It is the first detector of its kind with a large (30 tonnes), liquid scintillator neutron veto and water Cherenkov (1,000 tonnes) muon veto concentrically enveloping the dark matter target. An initial 1,422 kg*day exposure run with atmospheric argon yielded a null result of the dark matter search and zero background from radioactive sources. Operations with underground argon started in March 2015, and results from background-free 500-day exposure have been recently released. Argon-39 suppression in underground argon is proven to be more than 1000-fold, making much larger detectors free of instrumental background possible. Recently, DS-50 has also yielded exquisite sensitivity for low and very-low mass dark matter particles, below 10 GeV/c2.
I will review the DS-50 results and present the future of the DarkSide program, DS-20k. DS-20k is multi-tens of tons detector designed for a background-free exposure of 100 tonne-years, with a projected sensitivity to WIMP-nucleon cross section of better than 10-47 cm2 for WIMPs of mass 1 TeV/c2, a mass scale of special interest because above the reach of the LHC. Details of the DS-20k detector and R&D towards its finalization will be presented in the global context of direct dark matter searches.
