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Miramontes, A. S., Morgado, J. M., & Papavassiliou, J. (2026). Baryonic form factors of light pseudoscalar mesons. Phys. Lett. B, 878, 140531–7pp.
Abstract: Employing the Bethe-Salpeter formalism, we present a computation of the space-like baryonic form factor for the pion and kaon. In the exact isospin-symmetric limit this observable is forbidden by G-parity, so that any nonzero signal constitutes a direct probe of the quark mass difference m(d) – m(u). The form factors are evaluated in the impulse approximation using fully dressed quark propagators, meson Bethe-Salpeter amplitudes, and a dressed baryon-current vertex constrained by the vector Ward-Takahashi identity. The baryonic radius computed with this method for the pion is given by < r(B)(2)>(1/2)(pi+) = 0.043(2) fm, and is consistent with the available dispersive benchmarks. Our predictions for the kaons, namely < r(B)(2)>(1/2)(K+) = 0.265(7)fm and < r(B)(2)>(1/2)(K0) = 0.262(7) fm, indicate a larger spatial extent than in the pion case; these results have no dispersive counterparts, and are compatible with chiral QCD models.
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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). A method for luminosity determination based on real-time hit reconstruction with the LHCb silicon pixel detector. J. Instrum., 21(4), P04011–31pp.
Abstract: The data acquisition system of the upgraded LHCb experiment includes the fast reconstruction of all hits in the vertex locator (VELO) pixel detector at the beam-crossing rate of 40 MHz, implemented as on-the-fly clustering embedded in the firmware of the readout board FPGAs. The availability of a high rate of reconstructed clusters in real time enables a new fast approach for measuring luminosity and monitoring the LHCb luminous region, directly at the detector readout level. This methodology has been implemented as an array of real-time cluster counters in the VELO readout FPGAs and has been in operation since the start of the 2024 physics run of LHCb. This paper describes the methodology and its features and performance, both on proton-proton and lead-lead collision data. The method shows a statistical resolution better than the percent level, and a sensitivity to variable running conditions of the same level. This is achieved with an intrinsic time granularity better than 100 ms, undersampled to 3 s for analysis purposes. Nonlinear behaviour is compatible with zero in a luminosity range including the LHCb Run 3 operating point.
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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). Measurements of the production cross-sections of a Higgs boson in association with a vector boson and decaying into WW* with the ATLAS detector at √s=13 TeV. J. High Energy Phys., 08(8), 034–77pp.
Abstract: Measurements of the total and differential Higgs boson production cross-sections, via WH and ZH associated production using H -> WW* -> lvlv and H -> WW*. lvjj decays, are presented. The analysis uses proton-proton events delivered by the Large Hadron Collider at a centre-of-mass energy of 13TeV and recorded by the ATLAS detector between 2015 and 2018. The data correspond to an integrated luminosity of 140 fb(-1). The sum of the WH and ZH cross-sections times the H -> WW* branching fraction is measured to be 0.44(-0.09)(+0.10) (stat.) (+0.06)(-0.05) (syst.) pb, in agreement with the Standard Model prediction. Higgs boson production is further characterised through measurements of the differential cross-section as a function of the transverse momentum of the vector boson and in the framework of Simplified Template Cross-Sections.
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Razzaq, J., Fioresi, R., & Lledo, M. A. (2026). On fundamental theorems of invariant theory for the special linear supergroup (Vol. 704). Academic Press Inc Elsevier Science.
Abstract: The purpose of this paper is to prove the First and Second Fundamental Theorems of invariant theory for the complex special linear supergroup and discuss the superalgebra of invariants, via the super Pl & uuml;cker relations.
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Sanz, V. (2026). Artificial intelligence and symmetries: Learning, encoding, and discovering structure in physical data. Int. J. Mod. Phys. A, 41, 2630008–27pp.
Abstract: Symmetries play a central role in physics, organizing dynamics, constraining interactions, and determining the effective number of physical degrees of freedom. In parallel, modern artificial intelligence methods have demonstrated a remarkable ability to extract low-dimensional structure from high-dimensional data through representation learning. This review examines the interplay between these two perspectives, focusing on the extent to which symmetry-induced constraints can be identified, encoded, or diagnosed using machine learning techniques. Rather than emphasizing architectures that enforce known symmetries by construction, we concentrate on data-driven approaches and latent representation learning, with particular attention to variational autoencoders. We discuss how symmetries and conservation laws reduce the intrinsic dimensionality of physical datasets, and how this reduction may manifest itself through self-organization of latent spaces in generative models trained to balance reconstruction and compression. We review recent results, including case studies from simple geometric systems and particle physics processes, and analyze the theoretical and practical limitations of inferring symmetry structure without explicit inductive bias.
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