92 research outputs found
Study of cosmogenic activation above ground for the DarkSide-20k experiment
The activation of materials due to exposure to cosmic rays may become an important background source for experiments investigating rare event phenomena. DarkSide-20k, currently under construction at the Laboratori Nazionali del Gran Sasso, is a direct detection experiment for galactic dark matter particles, using a two-phase liquid-argon Time Projection Chamber (TPC) filled with 49.7 tonnes (active mass) of Underground Argon (UAr) depleted in 39Ar. Despite the outstanding capability of discriminating
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background in argon TPCs, this background must be considered because of induced dead time or accidental coincidences mimicking dark-matter signals and it is relevant for low-threshold electron-counting measurements. Here, the cosmogenic activity of relevant long-lived radioisotopes induced in the experiment has been estimated to set requirements and procedures during preparation of the experiment and to check that it is not dominant over primordial radioactivity; particular attention has been paid to the activation of the 120 t of UAr used in DarkSide-20k. Expected exposures above ground and production rates, either measured or calculated, have been considered in detail. From the simulated counting rates in the detector due to cosmogenic isotopes, it is concluded that activation in copper and stainless steel is not problematic. The activity of 39Ar induced during extraction, purification and transport on surface is evaluated to be 2.8% of the activity measured in UAr by DarkSide-50 experiment, which used the same underground source, and thus considered acceptable. Other isotopes in the UAr such as 37Ar and 3H are shown not to be relevant due to short half-life and assumed purification methods
Amazonian malaria vector anopheline relationships interpreted from ITS2 rDNA sequences
Latest results of dark matter detection with the DarkSide experiment
In this contribution the latest results of dark matter direct detection obtained by the DarkSide Collaboration are discussed. New limits on the scattering cross-section between dark matter particles and baryonic matter have been set. The results have been reached using the DarkSide-50 detector, a double-phase Time Projection Chamber (TPC) filled with 40Ar and installed at Laboratori Nazionali del Gran Sasso (LNGS). In 2018, the DarkSide Collaboration has performed three different types of analysis. The so-called high-mass analysis into the range between ∼ 10 GeV and ∼ 1000 GeV is discussed under the hypothesis of scattering between dark matter and Ar nuclei. The low-mass analysis, performed using the same hypothesis, extends the limit down to ∼1.8 GeV. Through a different hypothesis, that predicts dark matter scattering off the electrons inside of the Ar atom, it has been possible to set limits for sub-GeV dark matter masses
The present and future of QCD
This White Paper presents an overview of the current status and future perspective of QCD research, based on the community inputs and scientific conclusions from the 2022 Hot and Cold QCD Town Meeting. We present the progress made in the last decade toward a deep understanding of both the fundamental structure of the sub-atomic matter of nucleon and nucleus in cold QCD, and the hot QCD matter in heavy ion collisions. We identify key questions of QCD research and plausible paths to obtaining answers to those questions in the near future, hence defining priorities of our research over the coming decades
PO-0863: “First in Man” treatments with the MRI-linac provide clinical proof of the concept
Black hole spectroscopy via adiabatic invariant in a quantum corrected spacetime
Using the modified Kunstatter method, which employs as proper frequency the imaginary part instead of the real part of the quasinormal modes, the entropy spectrum and area spectrum of the modified Schwarzschild black holes in gravity’s rainbow are investigated. In the current study, two cases of modified dispersion relations concerning energy dependent and energy independent speed of light are considered. The entropy spectra with equal spacing are derived in these two cases. Furthermore, the obtained entropy spectra are independent of the energy of a test particle and are the same as the one of the usual Schwarzschild black hole. Also, the same area spectrum formulas are obtained in these different dispersion relations. However, due to the quantum effect of spacetime, the obtained area spectra are not equally spaced and are different from the one of the usual Schwarzschild black hole. Besides, in these two cases, the same black hole entropy formulas with logarithmic correction to the standard Bekenstein–Hawking area formula are obtained by the adiabatic invariant. The form of area spacing formulas and entropy formulas are independent of the particle’s energy, but the area spacing and entropy can have energy dependence through the area
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