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Borexino is a liquid scintillation detector located deep underground at the Laboratori Nazionali del Gran Sasso (LNGS, Italy). Thanks to the unmatched radio purity of the scintillator, and to the well understood detector response at low energy, a new limit on the stability of the electron for decay into a neutrino and a single monoenergetic...

We report an improved geoneutrino measurement with Borexino from 2056 days of data taking. The present exposure is (5.5±0.3)×1031 proton×yr. Assuming a chondritic Th/U mass ratio of 3.9, we obtain 23.7-5.7+6.5(stat)-0.6+0.9(sys) geoneutrino events. The null observation of geoneutrinos with Borexino alone has a probability of 3.6×10-9 (5.9σ). A...

Borexino is a liquid scintillator detector primary designed to observe solar neutrinos. Thanks to the intrinsic radiopurity achieved in the scintillator, Borexino already measured the rate of neutrinos coming from the pp, pep, 7Be and 8B processes which take place inside the Sun. Due to its low background level as well as its position in Italy,...

Several observed anomalies in the neutrino sector could be explained by a fourth (sterile) neutrino with a squared mass difference in the order of 1eV2 to the other three standard neutrinos. This hypothesis can be tested with an artificial kCi antineutrino (Ce-144/Pr-144) source deployed near or inside a large low background detector like...

Most of the neutrino oscillation results can be explained by the three-neutrino paradigm. However several anomalies in short baseline oscillation data (L/E of about 1 m/MeV) could be interpreted by invoking a light sterile neutrino. This new state would be separated from the standard neutrinos by a squared mass difference Δm2new ∼ 0.1-1 eV2 and...

The DarkSide project at Laboratori Nazionali del Gran Sasso (LNGS) is a dark matter direct search experiment based on the detection of rare nuclear recoils possibly induced by hypothetical dark matter particles, which are supposed to be neutral, massive (> 10 GeV) and weakly interact- ing (WIMP). DarkSide aims to perform background-free WIMP...

We report the first results of DarkSide-50, a direct search for dark matter operating in the underground Laboratori Nazionali del Gran Sasso (LNGS) and searching for the rare nuclear recoils possibly induced by weakly interacting massive particles (WIMPs). The dark matter detector is a Liquid Argon Time Projection Chamber with a (46.4±0.7)kg...

The DarkSide experiment is designed for the direct detection of Dark Matter with a double phase liquid Argon TPC operating underground at Laboratori Nazionali del Gran Sasso. The TPC is placed inside a 30 tons liquid organic scintillator sphere, acting as a neutron veto, which is in turn installed inside a 1 kt water Cherenkov detector. The...

A Geant4-based Monte Carlo package named G4DS has been developed to simulate the response of DarkSide-50, an experiment operating since 2013 at LNGS, designed to detect WIMP interactions in liquid argon. In the process of WIMP searches, DarkSide-50 has achieved two fundamental milestones: the rejection of electron recoil background with a power...

We report measurements of the charged daughter fraction of 218Po as a result of the 222Rn alpha decay, and the mobility of 218Po+ ions, using radon-polonium coincidences from the 238U chain identified in 532 live-days of DarkSide-50 WIMP-search data. The fraction of 218Po that is charged is found to be 0.37 ± 0.03 and the mobility of 218Po+ is...

The DarkSide experiment aims to perform a background-free direct search for dark matter with a dual-phase argon TPC. The current phase of the experiment, DarkSide-50, is acquiring data at Laboratori Nazionali del Gran Sasso and produced the most sensitive limit on the WIMP-nucleon cross section ever obtained with a liquid argon target (2.0 ×...

Liquid argon is a bright scintillator with potent particle identification properties, making it an attractive target for direct-detection dark matter searches. The DarkSide-50 dark matter search here reports the first WIMP search results obtained using a target of low-radioactivity argon. DarkSide-50 is a dark matter detector, using a two-phase...