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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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Dimitriou, A., Figueroa, D. G., Simakachorn, P., & Zaldivar, B. (2026). Cosmic string gravitational wave backgrounds at LISA: I. Signal survey, template reconstruction, and model comparison. J. Cosmol. Astropart. Phys., 05(5), 037–90pp.
Abstract: We present a catalog of gravitational wave background (GWB) signal templates from cosmic-string networks, based on relevant models proposed in the literature. We classify templates as conventional, based on standard cosmology and Nambu-Goto results (VOS and BOS), and beyond conventional, based on modifications of a) the loop number density (LRS, super, metastable, current-carrying strings), b) the expansion history (nonstandard cosmologies, extra degrees of freedom, either thermal or secluded), or c) the loop properties (birth length, power emission). Using the SBI package GWBackFinder: https://github.com/AndronikiDimitriou/GWBackFinder, we quantify the reconstruction precision of each signal by LISA, scanning over their parameter space, and performing model comparisons. For conventional signals, LISA reconstructs the tension G & micro; with an error less than or similar to 10% for G & micro; >= 5 & centerdot;10-15, which decreases down to 2-3% for G & micro; >= 10-12. BOS and VOS modelings become distinguishable confidently for G & micro; >= 5 & centerdot; 10-13. For beyond-conventional signals, we identify SNR and error-threshold intervals for each parameter, and determine (for few examples) the regions where they can be distinguished from conventional signals. Analogous quality reconstruction studies of cosmic-string GWBs, superimposed over leading astrophysical foregrounds in the LISA window, will be presented in a series of upcoming papers.
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ATLAS Collaboration(Aad, G. et al), Aikot, A., Amos, K. R., Bouchhar, N., Cabrera Urban, S., Cantero, J., et al. (2026). Search for signatures of electroweakinos with photons, jets, and large missing transverse momentum in √s=13 TeV pp collisions with the ATLAS detector. J. High Energy Phys., 04(4), 150–47pp.
Abstract: A search for final states characterised by at least one isolated high transverse-momentum photon, jets and large missing transverse momentum is presented. Such a final state might occur in gauge-mediated supersymmetric models where a pair of binos and higgsinos mix to form neutralinos, one of which decays into a photon plus a gravitino while the other decays into a Higgs boson, a Z boson or a photon, plus a gravitino. The search is performed using the full Run-2 data sample of 140 fb(-1) of root s = 13 TeV proton-proton collisions collected by the ATLAS detector at the Large Hadron Collider. No significant excess of events is observed above the Standard Model prediction and model-dependent exclusion limits at the 95% confidence level are set. These limits are interpreted in terms of the masses of gauginos, which are excluded up to 1.2 TeV depending on their branching ratios, and on their branching ratios as a function of their mass.
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