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Abstract The search for neutrino events in correlation with 42 most intense fast radio bursts (FRBs) has been performed using the Borexino dataset from 05/2007 to 06/2021. We have searched for signals with visible energies above 250 keV within a time window of $$\pm \, 1000$$ ± 1000  s corresponding to detection time of a particular FRB. We also applied an alternative approach based on searching for specific shapes of neutrino-electron scattering spectra in the full exposure data of the Borexino detector. In particular, two incoming neutrino spectra were considered: the monoenergetic line and the spectrum expected from supernovae. The same spectra were considered for electron antineutrinos detected through inverse beta-decay reaction. No statistically significant excess over the background was observed. As a result, the strongest upper limits on FRB-associated neutrino fluences of all flavors have been obtained in the 0.5–50 MeV neutrino energy range. 

The SABRE (Sodium-iodide with Active Background REjection) experiment is a new detector based on NaI(Tl) scintillating crystals for the dark matter detection through the annual modulation. With ultra-pure crystals and an active veto system, based on liquid scintillator surrounding the crystal array, SABRE will reach unprecedented low background and the highest sensitivity among the present NaI(Tl) experiments. Moreover SABRE will be the first dark matter search with twin detectors located in the North and South hemispheres, in Gran Sasso National Laboratories (LNGS), Italy, and Stawell Underground Laboratories (SUPL), Australia, respectively. The double location will help to quantify possible seasonal effects, and is a unique feature to identify a modulation of dark matter origins. SABRE is presently in the Proof-of-Principle (PoP) phase, with the goal to measure the crystal intrinsic and cosmogenic backgrounds of one 5 kg crystal and the active veto efficiency. We have performed a full geometry Monte Carlo simulation in order to evaluate the background contributions in the two distinct operation modes foreseen for the PoP: the potassium Measurement Mode (KMM) and the Dark Matter Measurement Mode (DMM), where the liquid scintillator detector is used in coincidence or anti-coincidence with the crystal, respectively. This paper presents the results of a detailed background simulation and the expected sensitivity for the SABRE full scale experiment.