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ATLAS Collaboration(Aad, G. et al), Ahuja, S., Aikot, A., Cabrera Urban, S., Cantero, J., Carrion Martinez, C., et al. (2026). Evidence of Higgs Boson Inclusive Production at High Transverse Momentum Decaying to a Pair of b-Quarks with the ATLAS Detector. Phys. Rev. Lett., 137(7), 071801–24pp.
Abstract: This Letter reports on the first evidence of inclusive Higgs-boson production at high transverse momentum in the b (b) over bar final state, reconstructed in a single large-radius jet. The results are based on proton-proton collision data recorded by the ATLAS detector at the Large Hadron Collider at a center-of-mass energies of 13 and 13.6 TeV, corresponding to a total integrated luminosity of 301 fb(-1). The study profits from the large background suppression provided by the use of a new transformer-based algorithm for jet identification and the sharper mass and transverse momentum, p(T), resolution from a dedicated regression model. The yield relative to the standard model prediction for Higgs bosons produced at p(T) larger than 450 GeV is measured to be 1.53 +/- 0.27)(+0.33)(-0.27) +/- 0.17, where the first uncertainty is statistical, the second is experimental systematic, and the third accounts for theory systematic, corresponding to an observed (expected) significance of 3.8 sigma(2.5 sigma) relative to the background-only hypothesis. Results are also obtained in three Higgs boson p(T) intervals and found to be compatible with standard model predictions, where the first uncertainty is statistical, the second is experimental systematic, and the third accounts for theory systematic.
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DUNE Collaboration(Abbaslu, S. et al), Amar Es-Sghir, H., Amedo, P., Barenboim, G., Benitez Montiel, C., Capo, J., et al. (2026). Charge readout electronics for the DUNE horizontal drift far detector: design and performance in ProtoDUNE-HD. J. Instrum., 21(8), P08018–63pp.
Abstract: DUNE (Deep Underground Neutrino Experiment) is a long-baseline neutrino oscillation experiment currently under construction, whose far detectors will be the largest liquid argon time projection chambers ever built. This detector design calls for custom-built cryogenic front-end electronics to meet its performance requirements. This paper describes the charge readout electronics that will be used in the DUNE horizontal drift (HD) far detector and presents performance results using data from the ProtoDUNE-HD detector, a 770 ton liquid argon time projection chamber operated at the CERN Neutrino Platform in 2024 that served as the final prototype of the DUNE HD design.
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Granelli, A., Pascoli, S., & Rosauro-Alcaraz, S. (2026). Dark matter interpretation of the Super-Kamiokande antineutrino excess and predictions for JUNO. SciPost Phys., 21(4), 106–16pp.
Abstract: Super-Kamiokande has reported a small excess of electron antineutrino events in the 20 MeV energy range, in the search for the diffuse supernova neutrino background. We interpret this signal as a possible indication of dark matter that annihilates dominantly into neutrinos, pointing to a thermal dark matter candidate with s-wave annihilation and with mass in the tens of MeV range. This mass scale naturally fits into rich dark sector extensions of the Standard Model. Neutrino experiments, including JUNO, will be able to test this hypothesis in the coming years.
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König, K., Müller, P., Gesser, T., Burbach, E., Gandolfi, S., Heinz, M., et al. (2026). Accurate Charge Radius Measurement of 14C Confronts Ab Initio Theory. Phys. Rev. Lett., 137(18), 182501–10pp.
Abstract: Located at the neutron shell closure N = 8, the long-lived radioactive isotope 14C plays a critical role in geochronology and nuclear structure studies. Despite its widespread use, the nuclear charge radius of 14C has remained less precisely known than that of its stable counterpart 12C. Here, we report a high-precision determination of the 14C charge radius using collinear laser spectroscopy at the COALA setup at TU Darmstadt, improving upon the precision of previous muonic measurements by a factor of 5 and revealing a 1.9 sigma discrepancy of combined uncertainty, indicating a likely underestimated uncertainty in the muonic determination. This measurement challenges state-of-the-art ab initio nuclear theory calculations, including auxiliary field diffusion Monte Carlo, the valence-space in-medium similarity renormalization group, and the no-core shell model, augmented by neural-network techniques. With 12C and 14C now forming one of the most precisely characterized even-even isotope pairs, these results also enable improved QED tests.
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Zanon, I. et al, Gadea, A., & Valiente-Dobon, J. J. (2026). Inherited collectivity from shape-coexisting cores in the i13/2 rotational band of 189Hg. Phys. Rev. C, 114(5), 054305–10pp.
Abstract: Background: The neutron-deficient Hg isotopes provide one of the most prominent examples of nuclear shape coexistence. While the even-even nuclei have been extensively investigated, much less is known about how an unpaired neutron influences the evolution of collectivity in the odd-mass isotopes. Purpose: To determine lifetimes of low-spin states in 189Hg and investigate the evolution of collectivity in the rotational band built on the 13/2+ isomer through comparison with neighboring shape-coexisting Hg isotopes. Methods: Excited states in 189Hg were populated in the 160Gd(34S, 5n) 189Hg fusion-evaporation reaction at a beam energy of 185 MeV. The reaction channel of interest was selected by requiring coincidence with at least one neutron detected in the neutron wall array, while prompt gamma rays were measured with the GALILEO spectrometer. Lifetimes of low-lying states above the 13/2+ isomer were measured with the recoil-distance Doppler-shift method using the GALILEO plunger device. The experimental results were compared with total Routhian surface calculations. Results: Lifetimes of the 17/2+, 21/2+, and 25/2+ states were measured for the first time and the corresponding B(E2) strengths were extracted. The excitation energies and transition strengths closely follow the systematics observed in neighboring odd-and even-mass Hg isotopes, supporting the interpretation of the rotational sequence as the coupling of an i13/2 neutron to the weakly oblate structures of the neighboring even-even cores. The extracted B4/2-type ratio is significantly below unity, extending the occurrence of anomalous transition-strength ratios to this odd-mass nucleus. Total Routhian surface calculations reproduce the weakly oblate equilibrium deformation but not the observed evolution of the transition strengths. Conclusions: The present results indicate that the i13/2-based rotational band largely inherits the structural complexity of the neighboring shape-coexisting even-even Hg nuclei. They further demonstrate that electromagnetic transition strengths provide stringent constraints on the evolution of the underlying wave functions beyond those accessible from excitation energies or static mean-field descriptions alone.
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