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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 a heavy charged Higgs boson decaying into a W boson and a Higgs boson in final states with leptons and b-jets in √s=13 TeV pp collisions with the ATLAS detector. J. High Energy Phys., 02(2), 143–69pp.
Abstract: This article presents a search for a heavy charged Higgs boson produced in association with a top quark and a bottom quark, and decaying into a W boson and a 125 GeV Higgs boson h. The search is performed in final states with one charged lepton, missing transverse momentum, and jets using proton-proton collision data at root s = 13 TeV recorded with the ATLAS detector during Run 2 of the LHC at CERN. This data set corresponds to a total integrated luminosity of 140 fb(-1). The search is conducted by examining the reconstructed invariant mass distribution of the Wh candidates for evidence of a localised excess in the charged Higgs boson mass range from 250 GeV to 3 TeV. No significant excess of data over the expected background is observed and 95% confidence-level upper limits between 2.8 pb and 1.2 fb are placed on the production cross-section times branching ratio for charged Higgs bosons decaying into Wh.
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Rosario, I., Campanario, F., & Plaetzer, S. (2025). NLO QCD parton shower matching for pp → e+ νe μ- barνμ γ plus X 2,3,‡. Phys. Rev. D, 111(9), 094044–11pp.
Abstract: We present the implementation of a new interface in VBFNLO 3.0 supporting all diboson and triboson processes with fully leptonic final states, enabling next-to-leading order (NLO) + parton shower (PS) matched calculations. To demonstrate its capabilities, we study parton shower effects in the triboson production process pp -> e+nu e mu-nu<overline>mu gamma + X using Herwig 7.3 with NLO QCD amplitudes from VBFNLO 3.0. We estimate uncertainties from scale variations and analyze the impact of generation-level cuts on parton shower events. This study showcases the new interface's potential and provides insights into the interplay between fixed-order calculations and parton shower effects in multiboson production processes, crucial for precision measurements and beyond the Standard Model searches at the LHC and future colliders.
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Song, J., Yang, Z. Y., & Oset, E. (2025). Role of a0(1710) in the Ds plus -> ρ plus φ;ρ plus ω decays. Phys. Rev. D, 111(9), 094047–7pp.
Abstract: We look into the D+s-* rho+phi and D+s-* rho+omega weak decays recently measured by the BESIII collaboration, which proceed very differently in a first step of the weak decay. While the first reaction proceeds directly via external emission, the second one does not go via external nor internal emission, what prompted the experimental team to claim that it proceeds via W-annihilation. We show in this work that the unexpectedly large rate of the D+s-* rho+omega has a different explanation since is it naturally obtained once final state interaction of the rho+phi; rho+omega and K*+K*0 channels is taken into consideration. The interaction of these channels produces the a0(1710) resonance, predicted long ago as a molecular state of these coupled channels, and only recently observed, and it is the presence of this resonance what makes the effect of the final state interaction very important in the weak decays and provides a natural explanation of the experimental decay rates at a quantitative level. We also take into account the D+s-* rho+omega decay in P-and D-waves empirically, and show that a good reproduction of the experimental results is obtained in this case.
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NA64 Collaboration(Andreev, Y. M. et al), Molina Bueno, L., & Tuzi, M. (2025). Proof of principle for a light dark matter search with low-energy positron beams at NA64. J. High Energy Phys., 06(6), 256–39pp.
Abstract: Thermal light dark matter (LDM) with particle masses in the 1 MeV-1 GeV range could successfully explain the observed dark matter abundance as a relic from the primordial Universe. In this picture, a new feeble interaction acts as a “portal” between the Standard Model and LDM particles, allowing for the exploration of this paradigm at accelerator experiments. In the last years, the “missing energy” experiment NA64e at CERN SPS (Super Proton Synchrotron) has set world-leading constraints in the vector-mediated LDM parameter space, by exploiting a 100 GeV electron beam impinging on an electromagnetic calorimeter, acting as an active target. In this paper, we report a detailed description of the analysis of a preliminary measurement with a 70 GeV/c positron beam at NA64e, performed during summer 2023 with an accumulated statistics of 1.596 x 1010 positrons on target (hereafter referred to as e+OT). This data set was analyzed with the primary aim of evaluating the performance of the NA64e detector with a lower energy positron beam, towards the realization of the post-LS3 program. The analysis results, other than additionally probing unexplored regions in the LDM parameter space, provide valuable information towards the future NA64e positron campaign.
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Miramontes, A. S., Eichmann, G., & Alkofer, R. (2025). Timelike form factor for the anomalous process γ*π→ππ. Phys. Lett. B, 868, 139659–7pp.
Abstract: The form factor F-3 pi(s, t, u) for the anomalous process gamma*pi-pi pi is calculated in the isospin limit for several values of the light current-quark mass (i.e., the pion mass) using Dyson-Schwinger and Bethe-Salpeter equations. Beyond a quark interaction kernel representing gluon-mediated interactions, leading beyond-rainbow-ladder effects at low energies are incorporated by back-coupling pions as explicit degrees of freedom. Building upon an earlier calculation of the quark-photon vertex that captures the branch cut associated with the two-pion threshold and the p-meson resonance, the form factor F-3 pi(s, t, u) is determined for timelike Mandelstam s. In particular, predictions are made for the kinematics relevant to the Primakoff reaction studied with COMPASS/AMBER at CERN.
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