The most successful class of direct detection of WIMPs with masses from few GeV/c2 to TeV/c2 have utilized Liquid Xenon time projection chambers (TPCs). The XENON project adopted dual phase TPCs ...using ultra-pure liquid Xenon as both target and detection medium for WIMPs. The first ton-scale Liquid Xenon based TPC, XENON1T, is running at the Gran Sasso Laboratory. With an active mass inside the TPC of 2 tonnes, data were collected for 278.8 days live time. Within a fiducial mass of 1.3 tonne, this results in 1.0 tonne×year exposure. In the energy region of interest, the detector exhibits the lowest background ever obtained in direct dark matter search experiment. In these data no significant excess over background is found and the most stringent limits on WIMP-nucleon spin-independent elastic scattering cross section has been set for masses above 6 GeV/c2 with a minimum of 4.1×10−47cm2 at 30 GeV/c2.
Neutrino physics with DARWIN Benabderrahmane, M. L.
Journal of physics. Conference series,
09/2017, Letnik:
888, Številka:
1
Journal Article
Recenzirano
Odprti dostop
DARWIN (DARk matter WImp search with liquid xenoN) will be a multi-ton dark matter detector with the primary goal of exploring the entire experimentally accessible parameter space for weakly ...interacting massive particles (WIMPs) over a wide mass-range. With its 40 tonne active liquid xenon target, low-energy threshold and ultra-low background level, DARWIN can also search for other rare interactions. Here we present its sensitivity to low-energy solar neutrinos and to neutrinoless double beta decay. In a low-energy window of 2-30 keV a rate of 105/year, from pp and 7Be neutrinos can be reached. Such a measurement, with 1% precision will allow testing neutrinos models. DARWIN could also reach a competitive half-life sensitivity of 8.5 · 1027 y to the neutrinoless double beta decay (0νββ) of 136Xe after an exposure of 140 t×y of natural xenon. Nuclear recoils from coherent scattering of solar neutrinos will limit the sensitivity to WIMP masses below 5 GeV/c2, and the event rate from 8B neutrinos would range from a few to a few tens of events per tonne and year, depending on the energy threshold of the detector. Deviations from the predicted but yet unmeasured neutrino flux would be an indication for physics beyond the Standard Model
We report the first dark matter search results from XENON1T, a ∼2000-kg-target-mass dual-phase (liquid-gas) xenon time projection chamber in operation at the Laboratori Nazionali del Gran Sasso in ...Italy and the first ton-scale detector of this kind. The blinded search used 34.2 live days of data acquired between November 2016 and January 2017. Inside the (1042±12)-kg fiducial mass and in the 5,40 keV_{nr} energy range of interest for weakly interacting massive particle (WIMP) dark matter searches, the electronic recoil background was (1.93±0.25)×10^{-4} events/(kg×day×keV_{ee}), the lowest ever achieved in such a dark matter detector. A profile likelihood analysis shows that the data are consistent with the background-only hypothesis. We derive the most stringent exclusion limits on the spin-independent WIMP-nucleon interaction cross section for WIMP masses above 10 GeV/c^{2}, with a minimum of 7.7×10^{-47} cm^{2} for 35-GeV/c^{2} WIMPs at 90% C.L.
Abstract
The selection of low-radioactive construction materials is of utmost importance for the success of low-energy rare event search experiments. Besides radioactive contaminants in the bulk, the ...emanation of radioactive radon atoms from material surfaces attains increasing relevance in the effort to further reduce the background of such experiments. In this work, we present the
$$^{222}$$
222
Rn emanation measurements performed for the XENON1T dark matter experiment. Together with the bulk impurity screening campaign, the results enabled us to select the radio-purest construction materials, targeting a
$$^{222}$$
222
Rn activity concentration of
$$10\,\mathrm{\,}\upmu \mathrm{Bq}/\mathrm{kg}$$
10
μ
Bq
/
kg
in
$$3.2\,\mathrm{t}$$
3.2
t
of xenon. The knowledge of the distribution of the
$$^{222}$$
222
Rn sources allowed us to selectively eliminate problematic components in the course of the experiment. The predictions from the emanation measurements were compared to data of the
$$^{222}$$
222
Rn activity concentration in XENON1T. The final
$$^{222}$$
222
Rn activity concentration of
$$(4.5\pm 0.1)\,\mathrm{\,}\upmu \mathrm{Bq}/\mathrm{kg}$$
(
4.5
±
0.1
)
μ
Bq
/
kg
in the target of XENON1T is the lowest ever achieved in a xenon dark matter experiment.
Abstract
Terrestrial Gamma-ray Flashes (TGFs) are a prompt, high energy, very intense natural emission of gamma rays from Earth’s atmosphere. Consisting of an upward sub-millisecond bursts of gamma ...rays (energy up to one hundred MeV), TGFs are mostly generated in powerful thunderstorms by lightnings. Given their production mechanism, several TGF counterparts can be detected too (mostly radio waves, electron beams and neutrons from photo-production). To investigate the X- and gamma-ray components, the ideal experiment is a space-borne instrument, operating at Low Earth Orbit (LEO) and featuring a fast detector response, possibly with spectral abilities. The CubeSat space mission LIGHT-1, launched in December 21st, 2021 and deployed from the International Space Station (ISS) on February 3rd, 2022, has been tailored around such physics requirements and it represents the technological demonstrator of possible larger missions to detect and localize TGF events. LIGHT-1 will help in making advancements in the TGF current knowledge: TGF occurring rates, average ignition altitude, production mechanism and effects on daily life on Earth are yet to be fully modeled and understood. In this paper the main characteristics of LIGHT-1 mission and the first preliminary flight data are reported.
We characterize the neutron output of a deuterium–deuterium plasma fusion neutron generator, model 35-DD-W-S, manufactured by NSD/Gradel-Fusion. The measured energy spectrum is found to be dominated ...by neutron peaks at 2.2 MeV and 2.7 MeV. A detailed GEANT4 simulation accurately reproduces the measured energy spectrum and confirms our understanding of the fusion process in this generator. Additionally, a contribution of 14.1MeV neutrons from deuterium–tritium fusion is found at a level of 3.5%, from tritium produced in previous deuterium–deuterium reactions. We have measured both the absolute neutron flux as well as its relative variation on the operational parameters of the generator. We find the flux to be proportional to voltage V3.32±0.14 and current I0.97±0.01. Further, we have measured the angular dependence of the neutron emission with respect to the polar angle. We conclude that it is well described by isotropic production of neutrons within the cathode field cage.
A compact muon tracking system for didactic and outreach activities Antolini, R.; Candela, A.; Conicella, V. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
07/2016, Letnik:
824
Journal Article
Recenzirano
We present a cosmic ray telescope based on the use of plastic scintillator bars coupled to ASD-RGB1S-M Advansid Silicon Photomultipliers (SiPM) through wavelength shifter fibers. The system is ...comprised of 200 electronic channels organized into 10 couples of orthogonal planes allowing the 3D reconstruction of crossing muons. Two monolithic PCB boards have been designed to bias, readout all the SiPMs enclosed in the system, to monitor the working parameters and to remotely connect the detector. To make easier the display of muon tracks to non-expert users, two LED matrices, triggered by particle interactions, have been implemented. To improve the usability of the muon telescope, a controller board unit permits to select different levels of trigger and allows data acquisition for refined analyses for the more proficient user. A first prototype, funded by INFN and deployed in collaboration with NYUAD, is operating at the Toledo Metro station of Naples, while two further detectors will be developed and installed in Abu Dhabi in the next few months.
•A compact system for real time displaying of muon tracks is presented.•The system is based on scintillating plates composed of doped polystyrene bars.•By using SiPMs and corresponding LEDs the muon paths can be visualized.•The purpose of this system is to introduce the public to sub-nuclear particles.
Using the large acceptance apparatus FOPI, we study central collisions in the reactions (energies in A GeV are given in parentheses): 40Ca + 40Ca (0.4, 0.6, 0.8, 1.0, 1.5, 1.93), 58Ni + 58Ni (0.15, ...0.25, 0.4), 96Ru + 96Ru (0.4, 1.0, 1.5), 96Zr + 96Zr (0.4, 1.0, 1.5), 129Xe + CsI (0.15, 0.25, 0.4), 197Au + 197Au (0.09, 0.12, 0.15, 0.25, 0.4, 0.6, 0.8, 1.0, 1.2, 1.5). The observables include cluster multiplicities, longitudinal and transverse rapidity distributions and stopping, and radial flow. The data are compared to earlier data where possible and to transport model simulations.
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