25 research outputs found
Tagging and localisation of ionizing events using NbSi transition edge phonon sensors for Dark Matter searches
In the context of direct searches of sub-GeV Dark Matter particles with
germanium detectors, the EDELWEISS collaboration has tested a new technique to
tag ionizing events using NbSi transition edge athermal phonon sensors. The
emission of the athermal phonons generated by the Neganov-Trofimov-Luke effect
associated with the drift of electrons and holes through the detectors is used
to tag ionization events generated in specific parts of the detector localized
in front of the NbSi sensor and to reject by more than a factor 5 (at 90% C.L.)
the background from heat-only events that dominates the spectrum above 3 keV.
This method is able to improve by a factor 2.8 the previous limit on
spin-independent interactions of 1 GeV/c2 WIMPs obtained with the same detector
and data set but without this tagging technique.Comment: 13 pages, 11 figure
Temporal bone verrucous carcinoma: outcomes and treatment controversy
Verrucous carcinoma is a rare tumor that presents in the head and neck with the most common sites being the oral cavity and larynx. Fourteen cases of verrucous carcinoma of the temporal bone have been described in literature; this study aims to examine treatment outcomes and discuss the controversy surrounding postoperative radiation. The study design included a literature review along with individual case report in the setting of a tertiary care medical center. Outcome analysis of all cases of verrucous carcinoma of the temporal bone, which are documented in the English literature, and presentation of a single patient report including gross, histologic and radiologic analyses were performed. The longest recorded survival for verrucous carcinoma of the temporal bone occurs in patients treated with surgery alone. Poorer outcomes for patients treated with adjuvant (chemo)radiation may be due to more advanced stage of disease at the time of treatment. Early reports of radiation leading to tumor dedifferentiation or early recurrence are not supported by more recent studies. Whether adjuvant radiation therapy is indicated in verrucous carcinoma of the temporal bone remains controversial
First demonstration of 30 eVee ionization energy resolution with Ricochet germanium cryogenic bolometers
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. This represents an order of
magnitude improvement over the best ionization resolutions obtained on similar
heat-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. Additionally, we discuss the implications of these results
in the context of the future Ricochet experiment and its expected background
mitigation performance.Comment: 10 pages, 5 figures, 1 tabl
Fast neutron background characterization of the future Ricochet experiment at the ILL research nuclear reactor
The future Ricochet experiment aims at searching for new physics in the
electroweak sector by providing a high precision measurement of the Coherent
Elastic Neutrino-Nucleus Scattering (CENNS) process down to the sub-100 eV
nuclear recoil energy range. The experiment will deploy a kg-scale
low-energy-threshold detector array combining Ge and Zn target crystals 8.8
meters away from the 58 MW research nuclear reactor core of the Institut Laue
Langevin (ILL) in Grenoble, France. Currently, the Ricochet collaboration is
characterizing the backgrounds at its future experimental site in order to
optimize the experiment's shielding design. The most threatening background
component, which cannot be actively rejected by particle identification,
consists of keV-scale neutron-induced nuclear recoils. These initial fast
neutrons are generated by the reactor core and surrounding experiments
(reactogenics), and by the cosmic rays producing primary neutrons and
muon-induced neutrons in the surrounding materials. In this paper, we present
the Ricochet neutron background characterization using He proportional
counters which exhibit a high sensitivity to thermal, epithermal and fast
neutrons. We compare these measurements to the Ricochet Geant4 simulations to
validate our reactogenic and cosmogenic neutron background estimations.
Eventually, we present our estimated neutron background for the future Ricochet
experiment and the resulting CENNS detection significance.Comment: 14 pages, 14 figures, 1 tabl
Coherent elastic neutrino-nucleus scattering: Terrestrial and astrophysical applications
Coherent elastic neutrino-nucleus scattering (CENS) is a process in which neutrinos scatter on a nucleus which acts as a single particle. Though the total cross section is large by neutrino standards, CENS has long proven difficult to detect, since the deposited energy into the nucleus is keV. In 2017, the COHERENT collaboration announced the detection of CENS using a stopped-pion source with CsI detectors, followed up the detection of CENS using an Ar target. The detection of CENS has spawned a flurry of activities in high-energy physics, inspiring new constraints on beyond the Standard Model (BSM) physics, and new experimental methods. The CENS process has important implications for not only high-energy physics, but also astrophysics, nuclear physics, and beyond. This whitepaper discusses the scientific importance of CENS, highlighting how present experiments such as COHERENT are informing theory, and also how future experiments will provide a wealth of information across the aforementioned fields of physics
Coherent elastic neutrino-nucleus scattering: Terrestrial and astrophysical applications
Coherent elastic neutrino-nucleus scattering (CENS) is a process inwhich neutrinos scatter on a nucleus which acts as a single particle. Thoughthe total cross section is large by neutrino standards, CENS has longproven difficult to detect, since the deposited energy into the nucleus is keV. In 2017, the COHERENT collaboration announced the detection ofCENS using a stopped-pion source with CsI detectors, followed up thedetection of CENS using an Ar target. The detection of CENS hasspawned a flurry of activities in high-energy physics, inspiring newconstraints on beyond the Standard Model (BSM) physics, and new experimentalmethods. The CENS process has important implications for not onlyhigh-energy physics, but also astrophysics, nuclear physics, and beyond. Thiswhitepaper discusses the scientific importance of CENS, highlighting howpresent experiments such as COHERENT are informing theory, and also how futureexperiments will provide a wealth of information across the aforementionedfields of physics.<br
Tagging and localisation of ionizing events using NbSi transition edge phonon sensors for Dark Matter searches
International audienceIn the context of direct searches of sub-GeV Dark Matter particles with germanium detectors, the EDELWEISS collaboration has tested a new technique to tag ionizing events using NbSi transition edge athermal phonon sensors. The emission of the athermal phonons generated by the Neganov-Trofimov-Luke effect associated with the drift of electrons and holes through the detectors is used to tag ionization events generated in specific parts of the detector localized in front of the NbSi sensor and to reject by more than a factor 5 (at 90% C.L.) the background from heat-only events that dominates the spectrum above 3 keV. This method is able to improve by a factor 2.8 the previous limit on spin-independent interactions of 1 GeV/c2 WIMPs obtained with the same detector and data set but without this tagging technique
Tagging and localisation of ionizing events using NbSi transition edge phonon sensors for Dark Matter searches
International audienceIn the context of direct searches of sub-GeV Dark Matter particles with germanium detectors, the EDELWEISS collaboration has tested a new technique to tag ionizing events using NbSi transition edge athermal phonon sensors. The emission of the athermal phonons generated by the Neganov-Trofimov-Luke effect associated with the drift of electrons and holes through the detectors is used to tag ionization events generated in specific parts of the detector localized in front of the NbSi sensor and to reject by more than a factor 5 (at 90% C.L.) the background from heat-only events that dominates the spectrum above 3 keV. This method is able to improve by a factor 2.8 the previous limit on spin-independent interactions of 1 GeV/c2 WIMPs obtained with the same detector and data set but without this tagging technique
Search for sub-GeV Dark Matter via Migdal effect with an EDELWEISS germanium detector with NbSi TES sensors
The EDELWEISS collaboration reports on the search for Dark Matter (DM) particle interactions via Migdal effect with masses between MeVc to GeVc using a g cryogenic Ge detector sensitive to simultaneously heat and ionization signals and operated underground at the Laboratoire Souterrain de Modane in France. The phonon signal was read out using a Transition Edge Sensor made of a NbSi thin film. The detector was biased at V in order to benefit from the Neganov-Trofimov-Luke amplification and resulting in a resolution on the energy of electron recoils of eV (RMS) and an analysis threshold of eV. The sensitivity is limited by a dominant background not associated to charge creation in the detector. The search constrains a new region of parameter space for cross-sections down to cm and masses between and MeVc. The achieved low threshold with the NbSi sensor shows the relevance of its use for athermal-phonon sensitive devices for low-mass DM searches