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ATLAS Collaboration(Aad, G. et al), Amoros, G., Cabrera Urban, S., Castillo Gimenez, V., Costa, M. J., Escobar, C., et al. (2011). Search for supersymmetry in pp collisions at sqrt(s)=7 TeV in final states with missing transverse momentum and b-jets. Phys. Lett. B, 701(4), 398–416.
Abstract: Results are presented of a search for supersymmetric particles in events with large missing transverse momentum and at least one heavy flavour jet candidate in root s = 7 TeV proton proton collisions. In a data sample corresponding to an integrated luminosity of 35 pb(-1) recorded by the ATLAS experiment at the Large Hadron Collider, no significant excess is observed with respect to the prediction for Standard Model processes. For R-parity conserving models in which sbottoms (stops) are the only squarks to appear in the gluino decay cascade, gluino masses below 590 GeV (520 GeV) are excluded at the 95% C.L. The results are also interpreted in an MSUGRA/CMSSM supersymmetry breaking scenario with tan beta = 40 and in an SO(10) model framework.
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Hellgren, M., Papoulias, D. K., & Suhonen, J. (2025). Inelastic neutrino-nucleus scattering off 203/205Tl in terms of the nuclear recoil energy using a hybrid nuclear model. Phys. Lett. B, 868, 139624–7pp.
Abstract: Nuclear structure calculations in the context of a novel hybrid nuclear model, combining the nuclear shell model and the microscopic quasiparticle-phonon model are presented. The predictivity of the hybrid model is tested by computing inelastic neutral-current neutrino-nucleus scattering cross sections off the stable thallium isotopes. The cross sections are presented in terms of the incoming neutrino energy, taking also into account the effect of nuclear recoil energy. Also reported are the expected event rates assuming neutrinos emerging from pion-decay at rest and the diffuse supernova neutrino background. Regarding solar neutrino rates, new results are presented in the context of the hybrid model and compared with previously reported results based solely on nuclear shell model calculations, demonstrating the improved accuracy of the adopted hybrid model at higher neutrino energies.
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Kozakova, J. et al, Bernabeu, P., Lacasta, C., Solaz, C., & Soldevila, U. (2026). Evaluation of performance of the p-stop fabrication process variations in ATLAS18 strip sensors, pre-and post-irradiation. Nucl. Instrum. Methods Phys. Res. A, 1091, 171783–7pp.
Abstract: The High-Luminosity upgrade of the Large Hadron Collider (HL-LHC) requires the replacement of the ATLAS Inner Detector with a new all-silicon Inner Tracker (ITk). Radiation-hard n+-in-p micro-strip sensors were developed for use in the ITk. During quality control (QC) and quality assurance (QA) procedures performed on ATLAS18 production sensors and test chips, ATLAS ITk strip sensor institutes identified instances of low p-stop density in certain production batches. To investigate the origin of these issues and to try some technological improvements, two dedicated sample batches with four variations of the p-stop fabrication process were produced. These process types (1-4) were systematically evaluated to determine their effectiveness and uniformity. In total, 56 full-size sensors, along with numerous miniature sensors and test chips, were tested. A number of samples were used in the irradiation campaign reaching the maximum expected levels for the HL-LHC operation after 10 years – with neutrons up to 1.6 & times; 1015 neq/cm2, and with gamma rays from a 60Co source up to 66 Mrad. The goal of this evaluation program is to assess the impact of p-stop fabrication process variations on interstrip isolation performance and to provide feedback for future sensor development. This paper describes the applied test procedures and presents the corresponding results, which demonstrate good sensor performance for all investigated p-stop types. The findings confirm the reliability of the evaluated designs and identify specific advantages that can inform further optimization of strip sensor fabrication.
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