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Sonneveld, J., Bergauer, T., Casanova, R., Handerkas, H., Irmler, C., Jimenez-Sanchez, J., et al. (2027). The RD50-MPW4: A radiation hard HV CMOS sensor for future colliders. Nucl. Instrum. Methods Phys. Res. A, 1093, 172091–5pp.
Abstract: The former CERN RD50 collaboration develops monolithic active pixel high voltage (HV) CMOS sensors for future colliders with the aim of high radiation tolerance, good time resolution, and high granularity pixel detectors. The most recent prototype, the RD50-MPW4, was produced by LFoundry in December 2023 using a 150 nm CMOS process. It features a matrix of 64x64 pixels with a 62 μm pitch and employs a column-drain readout architecture. Compared to its predecessor, it now has separate analog and digital power domains and a new biasing scheme with a guard ring structure that supports bias voltages over 600 V. This contribution will discuss the design and latest results of the MPW4, where tests with unirradiated samples showed more than 99.9% efficiency, 16 μm spatial resolution and 10 ns timing resolution. Efficiencies of over 99% were achieved for samples irradiated to fluences of 1 & times;1015 1 MeV neq/cm2. A 3D map of the charge collection efficiency from a measurement with two-photon absorption laser is presented that nicely outlines the depletion depth of this radiation hard, high granularity monolithic active pixel sensor.
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Arguelles, C. A., Bertolez-Martinez, T., Burgos-Mondejar, A., Burns, A. K., Lopez-Pavon, J., & Salvado, J. (2026). Seafloor topography enhances KM3NeT sensitivity to ANITA-like events. J. High Energy Phys., 09(9), 229–31pp.
Abstract: In this article, we introduce the concept of topographic enhancement in the context of ultra-high-energy neutrino detection by underwater neutrino telescopes. We demonstrate that the local topography around KM3NeT/ARCA can increase the detection efficiency in scenarios involving long-lived particles by up to a factor of similar to 3 due to the presence of an underwater mountain range in the direction of Malta. We consider a simplified model-independent approach that parametrizes the new physics able to generate both track-like and cascade-like signals in neutrino telescopes. When explaining the KM3-230213A event with a diffuse dark flux hypothesis, including its azimuthal direction – in addition to the zenith angle – provides additional constraints on the parameter space. In this effective model, the observations by KM3NeT and ANITA-IV can be simultaneously explained, but a global tension with the lack of a corresponding detection in IceCube remains at 2.7 sigma. This work underscores the importance of incorporating topographic effects in the design and optimization of next-generation neutrino telescopes, as is done in the context of mountain-based detectors such as TAMBO. We present which can be used to easily extend this topographical analysis to other experiments.
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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). Calibration of the jet energy scale and resolution of small-radius jets using semileptonic t(t)over-bar events with the ATLAS detector. Eur. Phys. J. C, 86(8), 943–36pp.
Abstract: A measurement of correction factors for the hadronic jet energy scale and resolution in the ATLAS detector is presented. These correction factors account for differences between simulated and observed data. They are obtained by analysing a selection of top quark events collected in proton-proton collisions by ATLAS between the years 2015 and 2018 at a centre-of-mass energy root s = 13 TeV as well as in 2022 and 2023 at root s = 13.6 TeV. The impact of different jet energy scale or resolution corrections on the reconstructed mass of the hadronically decaying W boson from top-quark decays in simulation is quantified. The correction factors are extracted from a fit to the parameterised reconstructedW-boson mass distribution to data. The energy scale and resolution corrections are measured as a function of the jet transverse momentum between 20 and 200 GeV and absolute pseudorapidity less than 0.8. The uncertainties in the energy scale range from about 0.93% to about 1.7% for jets between 35 and 200 GeV, while for the energy resolution the uncertainties range from about 14 to 28%. The method presented will be used in conjunction with other techniques to further improve ATLAS jet energy scale and resolution precision.
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Cheng, H. Y., Guo, Z. H., He, X. G., Hou, Y. R., Kang, X. W., Kupsc, A., et al. (2027). CP violation studies at Super Tau-Charm Facility. Phys. Rep., 1210, 1–60.
Abstract: Charge-parity (CP) violation in the tau-charm energy region is a promising area for sensitive tests of Standard Model (SM) predictions and searches for new, beyond the SM physics. A future Tau-Charm Facility that operates at center-of-mass energies between 2.0 and 7.0 GeV, with a peak luminosity of 0.5 & times; 1035 cm-2 s-1, would provide huge numbers of hadrons and tau (tau) leptons that are produced in low-background environments and with well understood kinematic properties. In this report, prospects for unique studies of CP violation in the decay of charmed hadrons, and in the production and decay of hyperons and tau leptons at a next-generation tau-charm facility are discussed. In addition, opportunities for improved tests of CPT invariance test in K0-K & strns;0 mixing are presented. (c) 2026 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
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LHCb Collaboration(Aaij, R. et al), Fernandez Casani, A., Jaimes Elles, S. J., Libralon, S., Lucio Martinez, M., Martinez-Vidal, F., et al. (2026). CP Violation Analysis of Local and Nonlocal Amplitudes in the (B)over-bar0 → (K)over-bar*0μ+μ- Decay. Phys. Rev. Lett., 137(6), 061801–12pp.
Abstract: A search for CP violation in the (B) over bar (0) -> (K) over bar*(0)mu(+)mu(-) decay is performed using proton-proton collision data collected by the LHCb experiment during Run 1 and Run 2, corresponding to an integrated luminosity of 8.4 fb(-1). The analysis exploits the full angular distribution of the decay, providing sensitivity to CP-violating effects in both vector and axial-vector contributions to this flavor-changing neutral-current process. The complex Wilson coefficients are determined within the weak effective theory through an unbinned maximum-likelihood fit to the angular observables, incorporating nonlocal hadronic amplitudes across the full dimuon mass spectrum. The precision of the CP-violation observables is improved by an order of magnitude relative to previous measurements, with the imaginary parts of the Wilson coefficients now determined more precisely than the real parts. No significant CP violation is observed, and the results are consistent with the standard model.
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