Gao, F., Harz, J., Hati, C., Lu, Y., Oldengott, I. M., & White, G. (2025). Baryogenesis and first-order QCD transition with gravitational waves from a large lepton asymmetry. J. High Energy Phys., 06(6), 247–48pp.
Abstract: A large primordial lepton asymmetry can lead to successful baryogenesis by preventing the restoration of electroweak symmetry at high temperatures, thereby suppressing the sphaleron rate. This asymmetry can also lead to a first-order cosmic QCD transition, accompanied by detectable gravitational wave (GW) signals. By employing next-to-leading order dimensional reduction we determine that the necessary lepton asymmetry is approximately one order of magnitude smaller than previously estimated. Incorporating an updated QCD equation of state that harmonizes lattice and functional QCD outcomes, we pinpoint the range of lepton flavor asymmetries capable of inducing a first-order cosmic QCD transition. To maintain consistency with observational constraints from the Cosmic Microwave Background and Big Bang Nucleosynthesis, achieving the correct baryon asymmetry requires entropy dilution by approximately a factor of ten. However, the first-order QCD transition itself can occur independently of entropy dilution. We propose that the sphaleron freeze-in mechanism can be investigated through forthcoming GW experiments such as μAres.
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Almanza Soto, M. (2025). Design, prototyping, and test of a Highly Compact and Granular Electromagnetic Calorimeter for the LUXE experiment. Nucl. Instrum. Methods Phys. Res. A, 1080, 170679–6pp.
Abstract: The LUXE experiment will investigate the strong-field QED regime by using the interactions of high-energy electrons from the European XFEL in a powerful laser field. It will measure the production of electron-positron pairs as a function of the laser field strength, up to the non-perturbative non-linear regime. LUXE foresees a positron detection system consisting of a tracker and a granular and unprecedentedly compact silicon-tungsten electromagnetic sandwich calorimeter (ECAL-P). The ECAL-P has been designed to cope with the wide range of the expected number of positrons per bunch crossing. In addition, the energy distribution of the positrons has to be measured on top of a widely spread low-energy background. The ECAL-P is composed of tungsten absorber plates interspersed with thin sensor planes, consisting of silicon pad sensors, flexible Kapton printed circuit planes, and carbon fiber support. The sensor planes are less than 1 mm thick and will be read using dedicated front-end ASICs in 130 nm technology (FLAXE) and FPGAs for data pre-processing. GaAs sensor planes with integrated readout strips are also being considered as an alternative to silicon. Prototypes of individual sensor planes have been tested in a 5 GeV electron beam. A full compact calorimeter tower of up to 90 x 90 x 600 mm3 (15 X0) will be produced and tested in an electron beam. The design challenges, sensor characterization, prototyping, integration, commissioning, and the available results from a beam test in 2022 are discussed.
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Boudagga, R. et al, Lacasta, C., Marinas, C., Mazorra de Cos, J., Molina-Bueno, L., & Vobbilisetti, V. (2025). Upgrade of the Belle II vertex detector with depleted monolithic CMOS active sensors. Nucl. Instrum. Methods Phys. Res. A, 1080, 170677–4pp.
Abstract: The Belle II experiment at the SuperKEKB collider in Japan, which currently holds the world luminosity record for electron-positron collisions, plans to upgrade its vertex detector (VXD) to operate at a target luminosity of 6 x 1035 cm-2s-1. A new pixelated vertex detector (VTX) is under development, utilizing a monolithic CMOS pixel sensor named OBELIX (Optimized BELle II pIXel). The VTX design incorporates 5-6 layers with a total material budget below 2.5% X0. All layers will employ the OBELIX, adapted from the TJ-Monopix2 sensor initially designed for the ATLAS Inner Tracker (ITk) upgrade. The OBELIX sensor, designed using a 180 nm CMOS process, features an enhanced pixel matrix and additional functionalities compared to its predecessor. Laboratory tests and test beam characterization results on irradiated and unirradiated TJ-Monopix2 sensors have yielded promising results, confirming the key performance parameters for the OBELIX design. This paper reviews the overall design of the VTX and the OBELIX sensor and presents the latest results of the in-beam characterization of the TJ-Monopix2.
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LHCb Collaboration(Aaij, R. et al), Fernandez Casani, A., Jaimes Elles, S. J., Jashal, B. K., Libralon, S., Martinez-Vidal, F., et al. (2025). Measurement of the multiplicity dependence of Γ production ratios in pp collisions at √s=13 Tev. J. High Energy Phys., 05(5), 011–24pp.
Abstract: The Gamma(2S) and Gamma(3S) production cross-sections are measured relative to that of the Gamma(1S) meson, as a function of charged-particle multiplicity in proton-proton collisions at a centre-of-mass energy of 13TeV. The measurement uses data collected by the LHCb experiment in 2018 corresponding to an integrated luminosity of 2 fb(-1). Both the Gamma(2S)to-Gamma(1S) and Gamma(3S)-to-Gamma(1S) cross-section ratios are found to decrease significantly as a function of event multiplicity, with the Gamma(3S)-to-Gamma(1S) ratio showing a steeper decline towards high multiplicity. This hierarchy is qualitatively consistent with the comover model predictions, indicating that final-state interactions play an important role in bottomonia production in high-multiplicity events.
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Lozares, S., Tur, P., Ballester, F., Bundschuh, R. A., Gonzalez-Perez, V., Jaberi, R., et al. (2025). Head and neck and skin (HNS) GEC-ESTRO and BRAPHYQS working groups joint critical review of the use of Rhenium-188 in dermato-oncology. Clin. Transl. Radiat. Oncol., 53, 100991–9pp.
Abstract: Non-melanoma skin cancers are increasing globally, prompting the need for innovative, non-invasive treatment approaches. Radioactive rhenium (188Re) paste has emerged as an open-source radiation-based modality in dermato-oncology, offering a novel alternative to conventional radiotherapy and brachytherapy. In this review, a systematic literature search was conducted using PubMed, Scopus, Web of Science, and Google Scholar for studies published over the past 20 years. Data were extracted from case series, pilot studies, and clinical trials, with particular emphasis on response rates, dosimetric parameters, and treatment-associated toxicity. Findings from approximately 240 patients demonstrated complete response rates ranging from 86 % to 100 % after one or two treatment applications, while dosimetric analyses revealed a rapid dose fall-off that effectively confines the therapeutic effect to a tissue depth of 2-3 mm, with most adverse effects being mild and transient. Notably, 188Re differs from conventional brachytherapy (specifically high-dose-rate modality) due to its open-source application and unique dosimetric profile. The use of 188Re in clinical practice mandates a highly specialized, multidisciplinary team, including radiation oncologists, nuclear medicine specialists, and experienced medical physicists, and strict quality assurance protocols, thereby limiting its application to carefully selected cases. Although 188Re therapy offers a promising alternative for the treatment of superficial skin cancers, its distinct clinical and dosimetric characteristics warrant further randomized studies with extended follow-up to validate its efficacy and refine patient selection criteria under rigorous multidisciplinary oversight.
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