SABRE NaI(Tl) Dark Matter investigation at low radioactivity

The interaction rate of hypothesised Dark Matter particles in an Earth bound detector is expected to undergo an annual modulation due to the planet's orbital motion. The DAMA experiment has observed such a modulation with high significance in an array of scintillating NaI(Tl) crystals, however this results remains today unconfirmed. SABRE aims to perform a higher sensitivity measurement with NaI(Tl) crystals able to verify the claim in a model independent way, but also to investigate the nature of Dark Matter interaction and the characteristics of the Dark Matter halo. This will be possible thanks to a lower background in the signal region and a lower energy threshold: we are developing high purity NaI(Tl) crystals, recently matching the purity of DAMA; moreover SABRE will enforce a 4π active background rejection with liquid scintillator and photomultiplier tubes with a lower background and a higher quantum efficiency. Our future design includes a pair of twin detectors at LNGS (Laboratori Nazionali del Gran Sasso, Italy) and SUPL (Stawell Underground Physics Laboratory, Australia). The combined analysis of data sets from the two hemispheres will allow to identify any terrestrial contribution to the modulating signal. We present here the progresses made on crystal development, the status of the Proof-of-Principle detector currently being installed at LNGS and the potentiality of the future detectors.