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Measurements Of 161Tb Production Cross Section For Nuclear Data And Nuclear Medicine
No full textInternational audienceThe production of 161Tb, of particular interest in medicine for its theranostic approach, was studied. The production cross sections for natGd(d,x) reactions were measured. This enabled a refinement of the values present in the databases, which show disparities, and a determination of the purity that can be achieved by the 160Gd(d,x)161Tb (cum.) production route
Beauty hadron production in high energy proton-proton and heavy-ion collisions in the EPOS4HQ framework
No full textInternational audienceCharmed hadron observables from the RHIC to LHC energies have been very successfully described with the recently advanced EPOS4HQ event generator. Here we extend this investigation to the production of beauty hadrons in proton-proton (pp) and heavy ion (HI) collision
Tracing the impact of former uranium mine sites using stable Pb isotopes: A review
No full textInternational audienceTracing pollution originating from uranium (U) mining activities is a key challenge due to the diversity of U sources (geochemical background versus U-ore) and its daughter radionuclides. Among the available tracers that can be used to highlight the impact of these activities on the environment, the application of Pb stable isotopes is relevant. This paper is an overview of the use of Pb isotopes for tracing U-mining impacts due to mining and milling activities. For this purpose, this work outlines the different Pb isotope sources in the environment with a focus on the primary U-rich ores until the mineralized area. This information is an important prerequisite for the understanding of Pb fate during the physical and chemical processing of U-ores. Moreover, an important review regarding the Pb isotope composition of the different types of U mining waste is carried out. Finally, an additional part of analytical procedures including sample preparation and Pb isotopic analysis are also be presented
Search for quantum decoherence in neutrino oscillations with six detection units of KM3NeT/ORCA
No full textInternational audienceNeutrinos described as an open quantum system may interact with the environment which introduces stochastic perturbations to their quantum phase. This mechanism leads to a loss of coherence along the propagation of the neutrino a phenomenon commonly referred to as decoherence and ultimately, to a modification of the oscillation probabilities. Fluctuations in space-time, as envisaged by various theories of quantum gravity, are a potential candidate for a decoherence-inducing environment. Consequently, the search for decoherence provides a rare opportunity to investigate quantum gravitational effects which are usually beyond the reach of current experiments. In this work, quantum decoherence effects are searched for in neutrino data collected by the KM3NeT/ORCA detector from January 2020 to November 2021. The analysis focuses on atmospheric neutrinos within the energy range of a few GeV to . Adopting the open quantum system framework, decoherence is described in a phenomenological manner with the strength of the effect given by the parameters and . Following previous studies, a dependence of the type on the neutrino energy is assumed and the cases are explored. No significant deviation with respect to the standard oscillation hypothesis is observed. Therefore, CL upper limits are estimated as GeV and GeV for , and GeV and GeV for , respectively
Thermal axion production at hard and soft momenta
No full textInternational audienceHot axions, thermally produced in the Early Universe, would contribute to dark radiation and are thus subject to present and future constraints from . In this paper we quantify the contribution to and its uncertainty in models with axion-gluon couplings from thermal dynamics above the QCD transition. In more detail, we determine the leading-order thermal axion production rate for axion momenta of the order of the temperature adopting three different schemes for the incorporation of the collective dynamics of soft gluons. We show how these three schemes extrapolate differently into the regime of softer axion production, thus giving us a quantitative handle on the theory uncertainty of the rate. Upon solving the Boltzmann equation, we find that this theory uncertainty translates to an uncertainty of at most 0.002 for . The uncertainty from common momentum-averaged approximations to the Boltzmann equation is smaller. We also comment on existing rate determinations in the literature and discuss how QCD transition dynamics would need to be integrated into our results
Search for Neutrino Emission from GRB 221009A using the KM3NeT ARCA and ORCA detectors
No full textInternational audienceGamma-ray bursts are promising candidate sources of high-energy astrophysical neutrinos. The recent GRB 221009A event, identified as the brightest gamma-ray burst ever detected, provides a unique opportunity to investigate hadronic emissions involving neutrinos. The KM3NeT undersea neutrino detectors participated in the worldwide follow-up effort triggered by the event, searching for neutrino events. In this letter, we summarize subsequent searches, in a wide energy range from MeV up to a few PeVs. No neutrino events are found in any of the searches performed. Upper limits on the neutrino emission associated with GRB 221009A are computed
Cluster formation near midrapidity: How the production mechanisms can be identified experimentally
No full textInternational audienceThe formation of weakly bound clusters in the hot and dense environment at midrapidity is one of the surprising phenomena observed experimentally in heavy-ion collisions from a low center of mass energy of a few GeV up to an ultrarelativistic energy of several TeV. Three approaches have been advanced to describe the cluster formation: coalescence at kinetic freeze-out, cluster formation during the entire heavy-ion collision by potential interaction between nucleons, and deuteron production by hadronic kinetic reactions. Based on the parton-hadron-quantum molecular dynamics microscopic transport approach, which incorporates all three mechanisms for deuteron production, we identify experimental observables, which can discriminate these production mechanisms for deuterons
Astronomy potential of KM3NeT/ARCA
No full textInternational audienceThe KM3NeT/ARCA neutrino detector is currently under construction at 3500 m depth offshore Capo Passero, Sicily, in the Mediterranean Sea. The main science objectives are the detection of high-energy cosmic neutrinos and the discovery of their sources. Simulations were conducted for the full KM3NeT/ARCA detector, instrumenting a volume of 1 km, to estimate the sensitivity and discovery potential to point-like neutrino sources and an all-sky diffuse neutrino flux. This paper covers the reconstruction of track- and shower-like signatures, as well as the criteria employed for neutrino event selection. By leveraging both the track and shower observation channels, the KM3NeT/ARCA detector demonstrates the capability to detect the diffuse astrophysical neutrino flux within half a year of operation, achieving a 5 statistical significance. With an angular resolution below 0.1 for tracks and under 2 for showers, the sensitivity to point-like neutrino sources surpasses existing observed limits across the entire sky
Measurement of the radius dependence of charged-particle jet suppression in Pb–Pb collisions at <math altimg="si1.svg"><msqrt><mrow><msub><mrow><mi>s</mi></mrow><mrow><mi mathvariant="normal">NN</mi></mrow></msub></mrow></msqrt><mo linebreak="goodbreak" linebreakstyle="after">=</mo><mn>5.02</mn><mspace width="0.25em"/><mtext>TeV</mtext></math>
No full textInternational audienceThe ALICE Collaboration reports a differential measurement of inclusive jet suppression using pp and Pb–Pb collision data at a center-of-mass energy per nucleon–nucleon collision sNN=5.02 TeV. Charged-particle jets are reconstructed using the anti-kT algorithm with resolution parameters R=0.2, 0.3, 0.4, 0.5, and 0.6 in pp collisions and R=0.2, 0.4, 0.6 in central (0–10%), semi-central (30–50%), and peripheral (60–80%) Pb–Pb collisions. A novel approach based on machine learning is employed to mitigate the influence of jet background. This enables measurements of inclusive jet suppression in new regions of phase space, including down to the lowest jet pT≥40 GeV/c at R=0.6 in central Pb–Pb collisions. This is an important step for discriminating different models of jet quenching in the quark–gluon plasma. The transverse momentum spectra, nuclear modification factors, derived cross section, and nuclear modification factor ratios for different jet resolution parameters of charged-particle jets are presented and compared to model predictions. A mild dependence of the nuclear modification factor ratios on collision centrality and resolution parameter is observed. The results are compared to a variety of jet-quenching models with varying levels of agreement
Studying the interaction between charm and light-flavor mesons
No full textInternational audienceThe two-particle momentum correlation functions between charm mesons ( and ) and charged light-flavor mesons ( and K) in all charge-combinations are measured for the first time by the ALICE Collaboration in high-multiplicity proton-proton collisions at a center-of-mass energy of TeV. For and pairs, the experimental results are in agreement with theoretical predictions of the residual strong interaction based on quantum chromodynamics calculations on the lattice and chiral effective field theory. In the case of and pairs, tension between the calculations including strong interactions and the measurement is observed. For all particle pairs, the data can be adequately described by Coulomb interaction only, indicating a shallow interaction between charm and light-flavor mesons. Finally, the scattering lengths governing the residual strong interaction of the and systems are determined by fitting the experimental correlation functions with a model that employs a Gaussian potential. The extracted values are small and compatible with zero