72 research outputs found
Tendances du changement climatique observées dans les mesures pluviométriques en Rhénanie-du-Nord-Westphalie (Allemagne) depuis 1950 et leurs conséquences pour l'hydrologie urbaine
Optimiser la modélisation de l’écoulement des eaux pluviales pour la gestion des inondations en milieu urbain avec des ensembles de prévisions de radar à court terme (Nowcasts)
Bioconversion of lignocellulosic 'waste' to high-value food proteins: Recombinant production of bovine and human alpha(S1)-casein based on wheat straw lignocellulose
Amélioration de la résilience de la ville de Luebeck à des pluies importantes : le projet RainAhead
Impact du développement urbain et du changement climatique sur les systèmes de drainage urbain
Deep-underground dark matter search with a COSINUS detector prototype
Sodium iodide (NaI) based cryogenic scintillating calorimeters using quantum
sensors for signal read out have shown promising first results towards a
model-independent test of the annually modulating signal detected by the
DAMA/LIBRA dark matter experiment. The COSINUS collaboration has previously
reported on the first above-ground measurements using a dual channel readout of
phonons and light based on transition edge sensors (TESs) that allows for
particle discrimination on an event-by-event basis. In this letter, we outline
the first underground measurement of a NaI cryogenic calorimeter read out via
the novel remoTES scheme. A 3.67 g NaI absorber with an improved silicon light
detector design was operated at the Laboratori Nazionali del Gran Sasso, Italy.
A significant improvement in the discrimination power of /-events
to nuclear recoils was observed with a five-fold improvement in the nuclear
recoil baseline resolution, achieving = 441 eV. Furthermore, we
present a limit on the spin-independent dark-matter nucleon elastic scattering
cross-section achieving a sensitivity of (pb) with an exposure of
only 11.6 g d.Comment: 11 pages, 14 figure
Particle discrimination in a NaI crystal using the COSINUS remote TES design
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 gd of
exposure. With a 3.7 g NaI crystal, e/ events could be clearly
distinguished from nuclear recoils down to the nuclear recoil energy threshold
of 15 keV.Comment: 7 pages, 9 figure
High-Dimensional Bayesian Likelihood Normalisation for CRESST's Background Model
Using CaWO crystals as cryogenic calorimeters, the CRESST experiment
searches for nuclear recoils caused by the scattering of potential Dark Matter
particles. A reliable identification of a potential signal crucially depends on
an accurate background model. In this work we introduce an improved
normalisation method for CRESST's model of the electromagnetic backgrounds.
Spectral templates, based on Geant4 simulations, are normalised via a Bayesian
likelihood fit to experimental background data. Contrary to our previous work,
no assumption of partial secular equilibrium is required, which results in a
more robust and versatile applicability. Furthermore, considering the
correlation between all background components allows us to explain 82.7% of the
experimental background within [1 keV, 40 keV], an improvement of 18.6%
compared to our previous method.Comment: 24 pages, 14 figures, submitted to EPJ
Observation of a low energy nuclear recoil peak in the neutron calibration data of the CRESST-III Experiment
New-generation direct searches for low mass dark matter feature detection
thresholds at energies well below 100 eV, much lower than the energies of
commonly used X-ray calibration sources. This requires new calibration sources
with sub-keV energies. When searching for nuclear recoil signals, the
calibration source should ideally cause mono-energetic nuclear recoils in the
relevant energy range. Recently, a new calibration method based on the
radiative neutron capture on W with subsequent de-excitation via single
-emission leading to a nuclear recoil peak at 112 eV was proposed. The
CRESST-III dark matter search operated several CaWO-based detector
modules with detection thresholds below 100 eV in the past years. We report the
observation of a peak around the expected energy of 112 eV in the data of three
different detector modules recorded while irradiated with neutrons from
different AmBe calibration sources. We compare the properties of the observed
peaks with Geant-4 simulations and assess the prospects of using this for the
energy calibration of CRESST-III detectors.Comment: 8 pages, 4 figures; submitted to Phys. Rev.
- …