A
bstract
Neutrinoless double-beta decay is a key process in particle physics. Its experimental investigation is the only viable method that can establish the Majorana nature of neutrinos, providing ...at the same time a sensitive inclusive test of lepton number violation. CROSS (Cryogenic Rare-event Observatory with Surface Sensitivity) aims at developing and testing a new bolometric technology to be applied to future large-scale experiments searching for neutrinoless double-beta decay of the promising nuclei
100
Mo and
130
Te. The limiting factor in large-scale bolometric searches for this rare process is the background induced by surface radioactive contamination, as shown by the results of the CUORE experiment. The basic concept of CROSS consists of rejecting this challenging background component by pulse-shape discrimination, assisted by a proper coating of the faces of the crystal containing the isotope of interest and serving as energy absorber of the bolometric detector. In this paper, we demonstrate that ultra-pure superconductive Al films deposited on the crystal surfaces act successfully as pulse-shape modifiers, both with fast and slow phonon sensors. Rejection factors higher than 99.9% of
α
surface radioactivity have been demonstrated in a series of prototypes based on crystals of Li
2
MoO
4
and TeO
2
. We have also shown that point-like energy depositions can be identified up to a distance of
∼
1 mm from the coated surface. The present program envisions an intermediate experiment to be installed underground in the Canfranc laboratory (Spain) in a CROSS-dedicated facility. This experiment, comprising
∼
3
×
10
25
nuclei of
100
Mo, will be a general test of the CROSS technology as well as a worldwide competitive search for neutrinoless double-beta decay, with sensitivity to the effective Majorana mass down to 70 meV in the most favorable conditions.
High Impedance TES Bolometers for EDELWEISS Marnieros, S.; Armengaud, E.; Arnaud, Q. ...
Journal of low temperature physics,
06/2023, Letnik:
211, Številka:
5-6
Journal Article
Recenzirano
The EDELWEISS collaboration aims for direct detection of light dark matter using germanium cryogenic detectors with low threshold phonon sensor technologies and efficient charge readout designs. We ...describe here the development of Ge bolometers equipped with high impedance thermistors based on a Nb
x
Si
1−x
TES alloy. High aspect ratio spiral designs allow the TES impedance to match with JFET or HEMT front-end amplifiers. We detail the behavior of the superconducting transition properties of these sensors and the detector optimization in terms of sensitivity to a-thermal phonons. We report preliminary results of a 200 g Ge detector that was calibrated using
71
Ge activation by neutrons at the LSM underground laboratory.
Introduction
Le syndrome thyro-gastrique auto-immun (STGA) est l’association d’une thyroïdite et d’une gastrite auto-immunes chez un même patient. Le substrat génétique de cette polyendocrinopathie ...auto-immune est inconnu.
Patients et méthodes
Nous avons recueilli les données cliniques et génétiques (DNA lymphocytaire) de quatre familles belges (9 F/1H), avec STGA (Hashimoto ou Basedow). Un séquençage de l'exome entier (WES), identifie plusieurs gènes candidats. Un panel de 12 gènes est conçu ensuite pour les études tNGS, incluant ATP4A et PTH1R (découverts chez deux familles) et SLC4A2, SLC26A7, SLC26A9 et PTH2R découverts dans l’étude WES, et aussi SLC9A2, SLC9A4, KCNE2, KCNQ1 et KCNJ16 et CCKBR2. En outre, 40 individus en bonne santé ont été recrutés comme contrôles.
Résultats
L’étude WES révèle une nouvelle mutation dans les gènes ATP4A et PTH Récepteur 1. Un deuxième groupe de variants d’échangeurs épithéliaux SLC4A2, SLC26A7 et SLC26A9, régulant la sécrétion acide gastrique, sont découverts. L’inactivation de ces gènes échangeurs par CRISP, dans des cellules HEK293T, détermine une apoptose sur stress oxydant (H2O2), suggérant un rôle principal de ces gènes dans le contrôle des ROS, l’équilibre acido-base cellulaire et la pathogenèse du STGA.
Conclusions
A partir de l’étude de nos familles et d’une large étude internationale1, nous décrivons un nouveau modèle génétique contribuant à la physiopathologie du SGTA. Nos données apportent des nouvelles perspectives pour la prédiction et le diagnostic de ces maladies auto-immunes ainsi que pour la prise en charge clinique des patients.
Références
1Calvete, Reyes, Valdes-Socin & al. Cell 2021 Dec; 10(12): 3500
The sensitivities of light Dark matter particle searches with cryogenic detectors are mostly limited by large backgrounds of events that do not produce ionization signal. The CRYOSEL project develops ...a new technique, where this background in a germanium cryogenic detector is rejected by using the signals from a superconducting single electron device (SSED) sensor designed to detect the phonons emitted through the Neganov–Trofimov–Luke effect by the e
-
h
+
pairs as they drift in a nearby very high-field region. A tag on signals from this device should suppress the heat-only background. The measurement of the response to IR laser pulses of the first CRYOSEL prototype show the relevance of such sensor technology.
The
Ricochet
reactor neutrino observatory is planned to be installed at Institut Laue–Langevin starting in mid-2022. The scientific goal of the
Ricochet
collaboration is to perform a low-energy and ...percentage precision CENNS measurement in order to explore exotic physics scenarios beyond the standard model. To that end,
Ricochet
will host two cryogenic detector arrays: the CryoCube (Ge target) and the Q-ARRAY (Zn target), both with unprecedented sensitivity to
O
(10) eV nuclear recoils. The CryoCube will be composed of 27 Ge crystals of 38 g instrumented with NTD-Ge thermal sensor as well as aluminum electrodes operated at 10 mK in order to measure both the ionization and the heat energies arising from a particle interaction. To be a competitive CENNS detector, the CryoCube array is designed with the following specifications: a low-energy threshold (
∼
50
eV), the ability to identify and reject with a high efficiency the overwhelming electromagnetic backgrounds (gamma, beta, and X-rays), and a sufficient payload (
∼
1
kg). After a brief introduction of the future
Ricochet
experiment and its CryoCube, the current works and first performance results on the optimization of the heat channel, and the electrode designs will be presented. We conclude with a preliminary estimation of the CryoCube sensitivity to the CENNS signal within
Ricochet
.
The future
Ricochet
experiment aims to search for new physics in the electroweak sector by measuring the Coherent Elastic Neutrino-Nucleus Scattering process from reactor antineutrinos with high ...precision down to the sub-100 eV nuclear recoil energy range. While the
Ricochet
collaboration is currently building the experimental setup at the reactor site, it is also finalizing the cryogenic detector arrays that will be integrated into the cryostat at the Institut Laue Langevin in early 2024. In this paper, we report on recent progress from the Ge cryogenic detector technology, called the CryoCube. More specifically, we present the first demonstration of a 30 eVee (electron equivalent) baseline ionization resolution (RMS) achieved with an early design of the detector assembly and its dedicated High Electron Mobility Transistor (HEMT) based front-end electronics with a total input capacitance of about 40 pF. This represents an order of magnitude improvement over the best ionization resolutions obtained on similar phonon-and-ionization germanium cryogenic detectors from the EDELWEISS and SuperCDMS dark matter experiments, and a factor of three improvement compared to the first fully-cryogenic HEMT-based preamplifier coupled to a CDMS-II germanium detector with a total input capacitance of 250 pF. Additionally, we discuss the implications of these results in the context of the future
Ricochet
experiment and its expected background mitigation performance.
The aim of the SELENDIS project within the EDELWEISS collaboration is to observe single e
-
h
+
pairs in lightweight (3.3 g) cryogenic germanium bolometers with charge and phonon readout at biases up ...to
∼
100
V. These devices are ideal to characterize in detail the mechanism of charge creation and collection in cryogenic germanium detectors. Electron–hole pairs are produced in the bulk of the detector either by the injection of pulsed IR laser or by neutron activation of germanium inducing the
K
,
L
and
M
lines from
71
Ge electron capture decays. Low-energy laser pulses are also used to probe the single e
-
h
+
pair sensitivity of Ge bolometers. Preliminary results are used to compare these two modes of charge creation, an important step toward a detailed characterization of Ge bolometers for their use in sub-MeV dark matter searches.
Ricochet Progress and Status Augier, C.; Beaulieu, G.; Belov, V. ...
Journal of low temperature physics,
08/2023, Letnik:
212, Številka:
3-4
Journal Article
Recenzirano
Odprti dostop
We present an overview of recent progress toward the
Ricochet
coherent elastic neutrino nucleus scattering (CE
ν
NS) experiment. The ILL research reactor in Grenoble, France has been selected as the ...experiment site, after in situ studies of vibration and particle backgrounds. We present background rate estimates specific to that site, along with descriptions of the planned CryoCube and Q-Array detector payloads.
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