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Acerbi, F. et al, Cervera Villanueva, A., Garcia-Peris, M. A., Martin-Albo, J., Querol, M., Rocabado, J., et al. (2026). Cryogenic characterization of FBK NUV-HD-Cryo 3T SiPM sensors for the DUNE photon detection system. J. Instrum., 21(2), P02047–19pp.
Abstract: The Deep Underground Neutrino Experiment (DUNE) is a long-baseline neutrino experiment based in the U.S.A. and composed of a Near Detector (ND) complex at Fermi National Laboratory (FNAL), and a Far Detector (FD) complex located at the Sanford Underground Research Facility (SURF) similar to 1300 km distant. DUNE will study neutrino oscillations looking for unresolved issues of the Standard Model of particle physics (SM) such as CP violation in the leptonic sector, neutrino mass ordering and others, starting from the early 2030s. The FD, with a mass of similar to 17 kt, that will exploit both ionization and scintillation signals to detect neutrino interactions with Argon. Scintillating photons in LAr will be detected by the photon detection system (PDS) based on light collectors coupled to Silicon Photomultipliers (SiPMs). During a test campaign, different laboratories of the collaboration performed an investigation of the best SiPM candidates that fulfill the DUNE FD requirements. We identified two models of SiPM, produced by Hamamatsu Photonics K.K. (HPK) and Fondazione Bruno Kessler (FBK), respectively. In this paper, we focus on the FBK selected model showing its main features. We will describe the characterization protocol, the results at both room and cryogenic temperatures and the photon detection efficiency measurements.
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LHCb Collaboration(Aaij, R. et al), Fernandez Casani, A., Jaimes Elles, S. J., Jashal, B. K., Libralon, S., Lucio Martinez, M., et al. (2026). Measurement of charged-hadron distributions in heavy-flavor jets in proton-proton collisions at √s=13 TeV. J. High Energy Phys., 04, 029–36pp.
Abstract: Charged-hadron distributions in heavy-flavor jets are measured in proton-proton collisions at a center-of-mass energy of root s = 13TeV collected by the LHCb experiment. Distributions of the longitudinal momentum fraction, transverse momentum, and radial profile of charged hadrons are measured separately in beauty and charm jets. The distributions are compared to those previously measured by the LHCb collaboration in jets produced back-to-back with a Z boson, which in the forward region are primarily light-quark-initiated, to compare the hadronization mechanisms of heavy and light quarks. The observed differences between the heavy- and light-jet distributions are consistent with the heavy-quark dynamics expected to arise from the dead-cone effect, as well as with a hard fragmentation of the heavy-flavor hadron as previously measured in single-hadron fragmentation functions. This measurement provides additional constraints for the extraction of collinear and transverse-momentum-dependent heavy-flavor fragmentation functions and offers another approach to probing the mechanisms that govern heavy-flavor hadronization.
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Antusch, S., Levy, M., & Centelles Chulia, S. (2026). Gravity-assisted neutrino masses. Phys. Lett. B, 876, 140410–6pp.
Abstract: Gravity is generally expected to violate global symmetries, including lepton number. However, neutrino masses from the Planck-suppressed Weinberg operator are typically too small to account for oscillation data. We propose a new model-building approach to low-scale neutrino mass generation, in which an intermediate spontaneous symmetry-breaking scale generates masses and mixings in the heavy neutral lepton (HNL) sector, while leaving an unbroken residual symmetry Gres that forbids light-neutrino masses. The observed light-neutrino masses then arise because gravity breaks Gres via Planck-suppressed operators, inducing the small lepton-number violation required in low-scale seesaw constructions. The HNLs form pseudo-Dirac pairs, with masses potentially within reach of future colliders and complementary tests in precision searches such as charged lepton flavour violation (cLFV). As an illustration, we present a representative realisation of this class of models and show that, for O(1) operator coefficients, it predicts a region in the (MR, Theta 2)-plane that can be testable via displaced-vertex searches at the High-Luminosity (HL-)LHC and the FCC-ee.
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Domingo-Pardo, C., Lederer-Woods, C., & Mengoni, A. (2026). Constraining r-process nucleosynthesis via enhanced accuracy neutron-capture experiments. Eur. Phys. J. A, 62(4), 83–10pp.
Abstract: The isotopic abundances of r-process elements in the solar system are traditionally derived as residuals from the subtraction of s-process contributions from total solar abundances. However, the uncertainties in s-process nucleosynthesis – particularly those arising from Maxwellian Averaged Cross Sections (MACS) – propagate directly into the r-process residuals, affecting their reliability. Building upon the seminal work of Goriely (A&A 342:881-891, 1999), who introduced a multi-event s-process model to quantify these uncertainties, we revisit the problem using a simplified yet effective approach. By assuming that the relative uncertainty in s-process isotopic abundances scales linearly with the MACS uncertainties from data libraries (KADoNiS), we identify a subset of isotopes for which the r-process residuals remain significantly uncertain. Using updated solar abundances (Lodders in Space Sci Rev 221:23, 2025) and s-process contributions from Bisterzo et al. (ApJ 787:10, 2014), we present a short list of isotopes that are prime candidates for improved (n,gamma) measurements at CERN nTOF in the near future. Our analysis provides a practical framework for prioritizing future experimental efforts that will profit from upgrades and enhancements of the nTOF facility. It also highlights the need to revisit key neutron-capture cross sections to refine our understanding of the r-process isotopic abundance pattern, commonly used as a benchmark in stellar models of explosive nucleosynthesis.
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n_TOF Collaboration(Spelta, M. et al), Balibrea-Correa, J., Domingo-Pardo, C., Ladarescu, I., Lerendegui-Marco, J., & Tarifeño-Saldivia, A. (2026). First Results of the 64Ni(n,γ) Cross Section Measurement at n_TOF. Galaxies, 14(2), 29–8pp.
Abstract: The neutron capture cross section of 64Ni is an important parameter in nuclear astrophysics that is needed to accurately simulate stellar nucleosynthesis and validate stellar models. 64Ni is among the seeds of the s-process and its capture cross section has been found to have an important effect on the predicted abundances of many nuclei synthesized in Asymptotic Giant Branch (AGB) and massive stars. Despite its relevance, the measurements of the 64Ni(n,gamma) available in the literature are scarce and discrepant. For this reason, a new accurate time-of-flight measurement has been performed at the n_TOF facility at CERN, taking advantage of its high instantaneous neutron flux, and using a highly enriched 64Ni sample. The first preliminary results show important discrepancies with respect to the cross sections recommended in the most recent releases of the evaluated nuclear data libraries. In particular, a large resonance reported at 9.52 keV is not observed. As a consequence, a significant reduction in the Maxwellian-Averaged Cross Section (MACS) obtained from evaluated data libraries in the 5-25 keV thermal energy region is expected.
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