Future liquid-argon DarkSide-20k and Argo detectors, designed for direct dark matter search, will be sensitive also to core-collapse supernova neutrinos, via coherent elastic neutrino-nucleus scattering. This interaction channel is flavor-insensitive with a high-cross section, enabling for a high-statistics neutrino detection with target masses of ∼50 t and ∼360 t for DarkSide-20k and Argo respectively. Thanks to the low-energy threshold of ∼0.5 keV nr achievable by exploiting the ionization channel, DarkSide-20k and Argo have the potential to discover supernova bursts throughout our galaxy and up to the Small Magellanic Cloud, respectively, assuming a 11-M progenitor star. We report also on the sensitivity to the neutronization burst, whose electron neutrino flux is suppressed by oscillations when detected via charged current and elastic scattering. Finally, the accuracies in the reconstruction of the average and total neutrino energy in the different phases of the supernova burst, as well as its time profile, are also discussed, taking into account the expected background and the detector response.

Proportional electroluminescence (EL) in noble gases is used in two-phase detectors for dark matter searches to record (in the gas phase) the ionization signal induced by particle scattering in the liquid phase. The “standard” EL mechanism is considered to be due to noble gas excimer emission in the vacuum ultraviolet (VUV). In addition, there are two alternative mechanisms, producing light in the visible and near infrared (NIR) ranges. The first is due to bremsstrahlung of electrons scattered on neutral atoms (“neutral bremsstrahlung”, NBrS). The second, responsible for electron avalanche scintillation in the NIR at higher electric fields, is due to transitions between excited atomic states. In this work, we have for the first time demonstrated two alternative techniques of the optical readout of two-phase argon detectors, in the visible and NIR range, using a silicon photomultiplier matrix and electroluminescence due to either neutral bremsstrahlung or avalanche scintillation. The amplitude yield and position resolution were measured for these readout techniques, which allowed to assess the detection threshold for electron and nuclear recoils in two-phase argon detectors for dark matter searches. To the best of our knowledge, this is the first practical application of the NBrS effect in detection science.

Design and construction of a new detector to measure ultra low radioactiveisotope contamination of argon Article (Accepted Version) http://sro.sussex.ac.uk

Aria is a plant hosting a $${350}\,\hbox {m}$$ 350 m cryogenic isotopic distillation column, the tallest ever built, which is being installed in a mine shaft at Carbosulcis S.p.A., Nuraxi-Figus (SU), Italy. Aria is one of the pillars of the argon dark-matter search experimental program, lead by the Global Argon Dark Matter Collaboration. It was designed to reduce the isotopic abundance of $${^{39}\hbox {Ar}}$$ 39 Ar in argon extracted from underground sources, called Underground Argon (UAr), which is used for dark-matter searches. Indeed, $${^{39}\hbox {Ar}}$$ 39 Ar is a $$\beta $$ β -emitter of cosmogenic origin, whose activity poses background and pile-up concerns in the detectors. In this paper, we discuss the requirements, design, construction, tests, and projected performance of the plant for the isotopic cryogenic distillation of argon. We also present the successful results of the isotopic cryogenic distillation of nitrogen with a prototype plant.

AGILE, Astrorivelatore Gamma ad Immagini LEggero, is a small space mission of the Italian Space Agency (ASI) devoted to observations for astrophysics in the gamma ray energy range 30MeV-50GeV with a simultaneous window in the X-ray band 15keV-45keV. AGILE Payload is composed by four scientific detectors: a Tungsten-Silicon Tracker, a CsI MiniCalorimeter, a Silicon based X-ray imager and an anticoincidence system for particle background rejection. Moreover, the Payload is completed by a Power Supply Unit (PSU) and a Payload Data Handling Unit (PDHU) and by three ancillary sub-systems (a GPS receiver and two Star Sensors). The PDHU tasks are: the Payload scientific and ancillary sub-systems control, the operational modes management, the scientific data processing and the Telemetry and Telecommands management. The scientific data processing involves the gamma-ray photons filtering, the X-ray data acquisition and a Burst acquisition logic able to perform an on-board Burst coordinates determination. The HW and SW design and implementation is in charge of the Alenia Spazio S.p.A. -Laben. In this paper we present a general description of the PDHU and the guidelines for the scientific simulations and the HW and SW testing activities.