The Large Volume Detector (LVD) has been continuously taking data since 1992 at the INFN Gran Sasso National Laboratory. LVD is sensitive to neutrino bursts from gravitational stellar collapses with full detection probability over the Galaxy. We have searched for neutrino bursts in LVD data taken in 7335 days of operation. No evidence of neutrino signals has been found between June 1992 and December 2013. The 90% C.L. upper limit on the rate of core-collapse and failed supernova explosions out to distances of 25 kpc is found to be 0.114 y −1 .

Direct Dark Matter searches are nowadays one of the most fervid research topics with many experimental efforts devoted to the search for nuclear recoils induced by the scattering of Weakly Interactive Massive Particles (WIMPs). Detectors able to reconstruct the direction of the nucleus recoiling against the scattering WIMP are opening a new frontier to possibly extend Dark Matter searches beyond the neutrino background. Exploiting directionality would also prove the galactic origin of Dark Matter with an unambiguous signal-to-background separation. Indeed, the angular distribution of recoiled nuclei is centered around the direction of a

The purposes, tasks and design features of the new measuring system of the Cherenkov water detector NEVOD are discussed

We report the measurement of the time of flight of ∼17 GeV ν(μ) on the CNGS baseline (732 km) with the Large Volume Detector (LVD) at the Gran Sasso Laboratory. The CERN-SPS accelerator has been operated from May 10th to May 24th 2012, with a tightly bunched-beam structure to allow the velocity of neutrinos to be accurately measured on an event-by-event basis. LVD has detected 48 neutrino events, associated with the beam, with a high absolute time accuracy. These events allow us to establish the following limit on the difference between the neutrino speed and the light velocity: -3.8 × 10(-6) < (v(ν)-c)/c < 3.1 × 10(-6) (at 99% C.L.). This value is an order of magnitude lower than previous direct measurements.

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The Large Volume Detector (LVD), hosted in the INFN Laboratori Nazionali del Gran Sasso, is triggered by atmospheric muons at a rate of ∼ 0.1 Hz. The data collected over almost a quarter of century are used to study the muon intensity underground. The 50-million muon series, the longest ever exploited by an underground instrument, allows for the accurate longterm monitoring of the muon intensity underground. This is relevant as a study of the background in the Gran Sasso Laboratory, which hosts a variety of long-duration, low-background detectors. We describe the procedure to select muon-like events as well as the method used to compute the exposure. We report the value of the average muon flux measured from 1994 to 2017: I 0 µ = 3.35 ± 0.0005 stat ± 0.03 sys · 10 −4 m −2 s −1 . We show that the intensity is modulated around this average value due to temperature variations in the stratosphere. We quantify such a correlation by using temperature data from the European Center for Medium-range Weather Forecasts:we find an effective temperature coefficient α T = 0.94 ± 0.01 stat ± 0.01 sys , in agreement with other measurements at the same depth. We scrutinise the spectral content of the time series of the muon intensity by means of the Lomb-Scargle analysis. This yields the evidence of a 1-year periodicity, as well as the indication of others, both shorter and longer, suggesting that the series is not a pure sinusoidal wave. Consequently, and for the first time, we characterise the observed modulation in terms of amplitude and position of maximum and minimum on a year-by-year basis.When high-energy cosmic rays enter the atmosphere, they produce a large number of secondary particles, in a series of successive interactions with atmospheric nuclei, called extensive air showers (EAS). EAS particles produced in the upper atmosphere propagate longitudinally through the atmosphere: at ground level, the most abundant among them are muons, which are produced in the decay of short-lived mesons, namely charged pions and kaons. Thanks to their small energy loss, small cross-section and long lifetime, higher energy (above ∼ 1 TeV) muons can penetrate deeply underground. Thus, large acceptance instruments located underground, originally designed for, e.g., neutrino or proton decay studies, all have excellent capabilities for the study of high energy atmospheric muons.The Large Volume Detector (LVD) [1], located in the INFN Laboratori Nazionali del Gran Sasso (LNGS) at a minimal depth of 3100 m w.e., is one of such detectors. Despite the large amount of overhead rock, LVD is triggered by atmospheric muons at a rate of ∼ 0.1 Hz.Underground muons are exploited for a variety of physics analyses, most notably for the measurement of the flux and the composition of Galactic cosmic rays (see e.g., [2] and [3]) as well as for the search for anisotropies (see [4], [5] and [6]). Also, the study of muons underground allows for the measurement of the high-energy part (above 1 TeV) of the sea-level muon energy spectrum through the depth-intens...

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