COSINUS is a dark matter (DM) direct search experiment that uses sodium iodide (NaI) crystals as cryogenic calorimeters. Thanks to the low nuclear recoil energy threshold and event-by-event ...discrimination capability, COSINUS will address the long-standing DM claim made by the DAMA/LIBRA collaboration. The experiment is currently under construction at the Laboratori Nazionali del Gran Sasso, Italy, and employs a large cylindrical water tank as a passive shield to meet the required background rate. However, muon-induced neutrons can mimic a DM signal therefore requiring an active veto system, which is achieved by instrumenting the water tank with an array of photomultiplier tubes (PMTs). This study optimizes the number, arrangement, and trigger conditions of the PMTs as well as the size of an optically invisible region. The objective was to maximize the muon veto efficiency while minimizing the accidental trigger rate due to the ambient and instrumental background. The final configuration predicts a veto efficiency of 99.63 ± 0.16% and 44.4 ± 5.6% in the tagging of muon events and showers of secondary particles, respectively. The active veto will reduce the cosmogenic neutron background rate to 0.11 ± 0.02 cts
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kg
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1
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year
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1
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corresponding to less than one background event in the region of interest for the whole COSINUS-1
π
exposure of 1000 kg
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days.
The essays collected in Literary Location and Dislocation of Myth in the Colonial and Post/Colonial Anglophone World examine how narratives have conveyed the diverse experiences of territorial ...belonging and alienation in postcolonial communities by rewriting traditional myths or creating new ones.
Replacé dans une longue durée de l'imaginaire qui va du IVe siècle - celui d'Athanase qui écrivit la première Vie de saint Antoine - jusqu'à la fin du XVe siècle, avec le Mystère de saint Antoine en ...Viennois, en passant par les légendes dorées médiévales, saint Antoine l'ermite, « père des moines », révèle un nouveau visage. Le croisement des savoirs, faisant appel à l'anthropologie et au comparatisme, à l'histoire des idées et des croyances religieuses (pour expliquer le symbole du tau ou celui du cochon associés au saint), à l'histoire de l'art enfin (avec le témoignage d'Huysmans sur la représentation picturale des tentations), permet de scruter cette figure-clé de la «mythologie chrétienne». Ainsi, entre légende et mythe peut se définir, autour d'Antoine le mélancolique et l'initié, l'unité d'une tradition culturelle qui, par-delà les siècles et peut-être même les civilisations, fait dialoguer l'Orient et l'Occident, le texte et l'image, l'Antiquité, le Moyen Âge et la Modernité.
COSINUS is a dark matter (DM) direct search experiment that uses sodium iodide (NaI) crystals as cryogenic calorimeters. Thanks to the low nuclear recoil energy threshold and event-by-event ...discrimination capability, COSINUS will address the long-standing DM claim made by the DAMA/LIBRA collaboration. The experiment is currently under construction at the Laboratori Nazionali del Gran Sasso, Italy, and employs a large cylindrical water tank as a passive shield to meet the required background rate. However, muon-induced neutrons can mimic a DM signal therefore requiring an active veto system, which is achieved by instrumenting the water tank with an array of photomultiplier tubes (PMTs). This study optimizes the number, arrangement, and trigger conditions of the PMTs as well as the size of an optically invisible region. The objective was to maximize the muon veto efficiency while minimizing the accidental trigger rate due to the ambient and instrumental background. The final configuration predicts a veto efficiency of 99.63 \(\pm\) 0.16 \(\%\) and 44.4 \(\pm\) \(5.6\%\) in the tagging of muon events and showers of secondary particles, respectively. The active veto will reduce the cosmogenic neutron background rate to 0.11 \(\pm\) 0.02 cts\(\cdot\)kg$^{-1}$$\cdot\(year\)^{-1}\(, corresponding to less than one background event in the region of interest for the whole COSINUS-1\)\pi\( exposure of 1000 kg\)\cdot$days.
The COSINUS direct dark matter experiment situated at Laboratori Nazionali del Gran Sasso in Italy is set to investigate the nature of the annually modulating signal detected by the DAMA/LIBRA ...experiment. COSINUS has already demonstrated that sodium iodide crystals can be operated at mK temperature as cryogenic scintillating calorimeters using transition edge sensors, despite the complication of handling a hygroscopic and low melting point material. With results from a new COSINUS prototype, we show that particle discrimination on an event-by-event basis in NaI is feasible using the dual-channel readout of both phonons and scintillation light. The detector was mounted in the novel remoTES design and operated in an above-ground facility for 9.06 g\(\cdot\)d of exposure. With a 3.7 g NaI crystal, e\(^-\)/\(\gamma\) events could be clearly distinguished from nuclear recoils down to the nuclear recoil energy threshold of 15 keV.
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