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Depletion of atmospheric neutrino fluxes from parton energy loss
No full textInternational audienceThe phenomenon of fully coherent energy loss (FCEL) in the collisions of protons on light ions affects the physics of cosmic ray air showers. As an illustration, we address two closely related observables: hadron production in forthcoming proton-oxygen collisions at the LHC, and the atmospheric neutrino fluxes induced by the semileptonic decays of hadrons produced in proton-air collisions. In both cases, a significant nuclear suppression due to FCEL is predicted. The conventional and prompt neutrino fluxes are suppressed by in their relevant neutrino energy ranges. Previous estimates of atmospheric neutrino fluxes should be scaled down accordingly to account for FCEL
Synergies and prospects for early resolution of the neutrino mass ordering
No full textInternational audienceThe measurement of neutrino mass ordering (MO) is a fundamental element for the understanding of leptonic flavour sector of the Standard Model of Particle Physics. Its determination relies on the precise measurement of and using either neutrino vacuum oscillations, such as the ones studied by medium baseline reactor experiments, or matter effect modified oscillations such as those manifesting in long-baseline neutrino beams (LBB) or atmospheric neutrino experiments. Despite existing MO indication today, a fully resolved MO measurement () is most likely to await for the next generation of neutrino experiments: JUNO, whose stand-alone sensitivity is , or LBB experiments (DUNE and Hyper-Kamiokande). Upcoming atmospheric neutrino experiments are also expected to provide precious information. In this work, we study the possible context for the earliest full MO resolution. A firm resolution is possible even before 2028, exploiting mainly vacuum oscillation, upon the combination of JUNO and the current generation of LBB experiments (NOvA and T2K). This opportunity is possible thanks to a powerful synergy boosting the overall sensitivity where the sub-percent precision of by LBB experiments is found to be the leading order term for the MO earliest discovery. We also found that the comparison between matter and vacuum driven oscillation results enables unique discovery potential for physics beyond the Standard Model
Theories and Experiments for Testable Baryogenesis Mechanisms: A Snowmass White Paper
No full textInternational audienceThe baryon asymmetry of the Universe is one of the central motivations to expect physics beyond the Standard Model. In this Snowmass white paper, we review the challenges and opportunities in testing some of the central paradigms that predict physics at scales low enough to expect new experimental data in the next decade. Focusing on theoretical ideas and some of their experimental implications, in particular, we discuss neutron-antineutron transformations, flavor observables, next generation colliders, future neutron facilities, gravitational waves, searches for permanent electric dipole moments, decay and some future large underground experiments as methods to test post-sphaleron baryogenesis, electroweak baryogenesis, mesogenesis and low scale leptogenesis. Finally, we comment on the cases where high scale physics can be probed through some of these same mechanisms
The Arronax platform for proton flash irradiation: from beam production to the target
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Coherent elastic neutrino-nucleus scattering: Terrestrial and astrophysical applications
No full textInternational audienceCoherent 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
Nuclear data for light charged particle induced production of emerging medical radionuclides
No full textInternational audienceWhatever the radionuclide to be used in nuclear medicine, it is essential to know the expected yield during the production process, but also of all the possible radionuclidic impurities coproduced, that can have an impact on the product final quality, as well as in the related waste management. The availability of the majority of emerging radioisotopes, including the theranostic ones or pairs, is mainly limited by the fact that, for most of them, the optimal production route still needs to be strengthened if not defined in some cases. The aim of this work is to present a review on the charged particle induced nuclear cross sections to produce some emerging radionuclides for medical applications to show that all types of projectiles should be considered in the quest of producing medical radionuclides. An accurate analysis of the production routes is presented for some radionuclides ( 67 Cu, 47 Sc, 89 Zr, 103 Pd, 186g Re, 97 Ru, 211 At) chosen as examples to highlight (i) how the quality of the final product strongly depends on the chosen target/projectile/energy parameters set, (ii) how deuteron production routes may sometimes be more effective than the proton ones or lead to a different impurity profile and (iii) how α-particle beams may allow to bypass the limitations occurring when using Z = 1 beams. An overview of possible advantages and drawbacks of the cited production routes and of potential cross sections that still need to be measured, is also reported
Electrochemical co-deposition of Ni–GdO for composite thin targets preparation: Production of Tb as a case study
No full textInternational audienceIn the last years, 155Tb has attracted enormous interest due to its potential role in theranostics in nuclear medicine. To estimate its production yield, the aim of this study was to develop a method to prepare thin Gd-enriched-containing targets aimed at the 155Gd(d, 2n)155Tb nuclear cross section measurement. To this end, the electrochemical co-deposition method has been chosen to manufacture Ni–Gd2O3 composite targets. Several process parameters that have an impact on the deposit quality, have been investigated to increase the incorporation of Gd mass (up to 3 mg). To validate the concept, seven targets made by natural Gd were irradiated with deuteron beams at the GIP ARRONAX facility cyclotron, with an energy range ranging from 8 MeV to 30 MeV to extract the cross section values by using the stacked-foils method. Results obtained turned out to have great consistency with existing published data thus validating the proposed method. Therefore, an alternative target manufacturing concept aimed at cross section measurement is presented in this work
Couette flow of pentane in clay nanopores: Molecular dynamics simulation
No full textInternational audienceShear flow of n-pentane in slit nanopores between clay surfaces is investigated by molecular dynamics simulations. Pyrophyllite and hydrated Na-montmorillonite are considered as representative examples of hydrophobic and hydrophilic clay surfaces, respectively. The viscosity-density relations and slip lengths are calculated for both pentane-clay interfaces for different pore widths. The results show that the viscosity-density dependencies for n-pentane are not changed by the confinement in pores with sizes from 3 to 7 nm, compared to the bulk liquid. At the pyrophyllite-pentane interface the slip length is 0.29 nm on average for all studied densities and pore sizes. However, the slip length is negligible at the montmorillonite-pentane interface, likely due to the microscopic roughness of the interface between pentane and the adsorbed water layer. The orientation analysis shows some preference for pentane molecules ordering parallel to the wall surfaces, which is stronger in pyrophyllite pores compared to the montmorillonite, suggesting an influence of the details of fluid-wall interaction on the liquid structure in nanopore
Field flow fractionation (FFF): practical and experimental aspects
No full textInternational audienceThis chapter presents the most used FFF techniques and the main associated detectors. It addresses the applications according to the nature of the analytes, macromolecules, (sub) micron particles, and micrometric objects. Particular attention is paid to information obtained from characterization strategies involving field-flow fractionation either in possibly multitechnique coupling or as a sample preparation method offering gentle sorting of analytes