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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. (2025). First observation of the Λb0 → Λc+Ds- K+ K- decay and search for pentaquarks in the Λc+Ds- system. Phys. Rev. D, 112(5), 052013–14pp.
Abstract: The Lambda(0)(b) -> Lambda D-+(c)s(-) K+ K- decay is observed for the first time using the data sample from proton-proton collisions recorded at a center-of-mass energy of 13 TeV with the LHCb detector, corresponding to an integrated luminosity of 6 fb-1. The ratio of branching fraction to that of Lambda(0)(b) -> Lambda D-+(c)s(-) decays is measured as 0.0141 +/- 0.0019 +/- 0.0012, where the first uncertainty is statistical and the second systematic. A search for hidden-charm pentaquarks with strangeness is performed in the Lambda D-+(c)s(-) system. No evidence is found, and upper limits on the production ratio of Pc (c) over bars(4338)(0) and Pc (c) over bars(4459)(0) pentaquarks relative to the Lambda D-+(c)s(-) final state are set at the 95% confidence level as 0.12 and 0.20, respectively.
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Pinetti, E., Vodeb, V., Amerio, A., Cuoco, A., Camera, S., Fornengo, N., et al. (2025). Dark matter and galaxy cross-correlations with the Cherenkov Telescope Array Observatory. Phys. Rev. D, 112(12), 123010–23pp.
Abstract: The Cherenkov Telescope Array Observatory (CTAO) will be a ground-based Cherenkov telescope performing wide-sky surveys, ideal for anisotropy studies such as cross-correlations with tracers of the cosmic large-scale structure. Cross-correlations can shed light on high-energy 7-ray sources and potentially reveal exotic signals from particle dark matter. In this work, we investigate CTAO sensitivity to crosscorrelation signals between 7-ray emission and galaxy distributions. We find that by using dense, lowredshift catalogs like 2 MASS, and for integration times around 50 hours, this technique achieves sensitivities to both annihilating and decaying dark matter signals that are competitive with those from dwarf galaxy and cluster analyses.
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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. (2025). Spatial and temporal evaluations of the liquid argon purity in ProtoDUNE-SP. J. Instrum., 20(9), P09008–37pp.
Abstract: Liquid argon time projection chambers (LArTPCs) rely on highly pure argon to ensure that ionization electrons produced by charged particles reach readout arrays. ProtoDUNE Single-Phase (ProtoDUNE-SP) was an approximately 700-ton liquid argon detector intended to prototype the Deep Underground Neutrino Experiment (DUNE) Far Detector Horizontal Drift module. It contains two drift volumes bisected by the cathode plane assembly, which is biased to create an almost uniform electric field in both volumes. The DUNE Far Detector modules must have robust cryogenic systems capable of filtering argon and supplying the TPC with clean liquid. This paper will explore comparisons of the argon purity measured by the purity monitors with those measured using muons in the TPC from October 2018 to November 2018. A new method is introduced to measure the liquid argon purity in the TPC using muons crossing both drift volumes of ProtoDUNE-SP. For extended periods on the timescale of weeks, the drift electron lifetime was measured to be above 30 ms using both systems. A particular focus will be placed on the measured purity of argon as a function of position in the detector.
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ATLAS Collaboration(Aad, G. et al), Aikot, A., Amos, K. R., Bouchhar, N., Cabrera Urban, S., Cantero, J., et al. (2025). Search for t(t)over-bar H/A→t(t)over-bart(t)over-bar production in proton-proton collisions at √s=13 TeV with the ATLAS detector. Eur. Phys. J. C, 85(5), 573–36pp.
Abstract: A search is presented for a heavy scalar (H) or pseudo-scalar (A) predicted by the two-Higgs-doublet models, where the H/A is produced in association with a top-quark pair (t (t) over barH/A), and with the H/A decaying into a t (t) over bar pair. The full LHC Run 2 proton-proton collision data collected by the ATLAS experiment is used, corresponding to an integrated luminosity of 139 fb(-1). Events are selected requiring exactly one or two opposite-charge electrons or muons. Data-driven corrections are applied to improve the modelling of the t (t) over bar +jets background in the regime with high jet and b-jet multiplicities. These include a novel multi-dimensional kinematic reweighting based on a neural network trained using data and simulations. An H/A-mass parameterised graph neural network is trained to optimise the signal-to-background discrimination. In combination with the previous search performed by the ATLAS Collaboration in the multilepton final state, the observed upper limits on the t (t) over barH/A -> t (t) over bart (t) over bar production cross-section at 95% confidence level range between 14 fb and 5.0 fb for an H/A with mass between 400 GeV and 1000 GeV, respectively. Assuming that both the H and A contribute to the t (t) over bart (t) over bar cross-section, tan beta values below 1.7 or 0.7 are excluded for a mass of 400 GeV or 1000 GeV, respectively. The results are also used to constrain a model predicting the pair production of a colour-octet scalar, with the scalar decaying into a t (t) over bar pair.
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Bombacigno, F., Moretti, F., & Olmo, G. J. (2025). Gravitational waves in Palatini gravity for a non-minimal geometry-matter coupling. J. Cosmol. Astropart. Phys., 12(12), 030–33pp.
Abstract: We discuss the propagation of gravitational waves over a non-Riemannian spacetime, when a non-minimal coupling between the geometry and matter is considered in the form of contractions of the energy momentum tensor with the Ricci and co-Ricci curvature tensors. We focus our analysis on perturbations on a Minkowski background, elucidating how derivatives of the energy momentum tensor can sustain non-trivial torsion and non-metricity excitations, eventually resulting in additional source terms for the metric field. These can be reorganized in the form of d'Alembert operator acting on the energy momentum tensor and the equivalence principle can be reinforced at the linear level by a suitable choice of the parameters of the model. We show how tensor polarizations can exhibit a subluminal phase velocity in matter, evading the constraints found in General Relativity, and how this allows for the kinematic damping in specific configurations of the medium and of the geometry-matter coupling. These in turn define regions in the wavenumber space where propagation is forbidden, leading to the appearance of typical cut-off scale in the frequency spectrum.
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