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Di Meglio, F. P., & Hagedorn, C. (2025). Charged lepton flavour violation from inverse seesaw with flavour and CP symmetries. Nucl. Phys. B, 1018, 117020–45pp.
Abstract: We study charged lepton flavour violation in a scenario in which light neutrino masses are generated via the inverse seesaw mechanism with 3+3 gauge singlet fermions, N, and Sj, i, j = 1, 2, 3. Lepton mixing is predicted with the help of the flavour symmetries D(3 n2) and D(6 n2) combined with CP. In the neutral lepton sector, the non-trivial flavour structure is only encoded in the Dirac neutrino Yukawa matrix (the coupling relating left-handed lepton doublets and gauge singlets N,). Current experimental bounds on the processes mu- e y, mu- 3 e, μ- e conversion in nuclei and the tau lepton decays a-l y and a-3l, l = e, mu, do not constrain the considered parameter space of this scenario. Prospective limits on the decay mu- 3 e and μ- e conversion in aluminium instead can markedly reduce the available parameter space. We also comment on the effects of the heavy sterile states on light neutrino masses and lepton mixing.
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Muniz, C. R., Alencar, G., Cunha, M. S., & Olmo, G. J. (2025). Static and stationary black bounces inspired by loop quantum gravity. Phys. Rev. D, 112(2), 024018–14pp.
Abstract: We construct static and stationary versions of a black bounce geometry using as inspiration a line element that arises in loop quantum gravity (LQG) scenarios. Analyzing the line element from the framework of general relativity, we trace its origin to nonlinear electrodynamics with electric and magnetic charges and check the energy conditions (null energy condition, weak energy condition, and strong energy condition). By extending the geometry using the Simpson-Visser procedure, we construct a black hole- wormhole bounce structure, influenced by LQG parameters. We analyze the horizon structure to constrain parameters for black holes and wormholes, and examine curvature and new sources, including a phantomtype scalar field, to ensure spacetime regularity and adherence to energy conditions. Thermodynamic properties are also studied, revealing the existence of remnants and phase transitions. Additionally, we derive a rotating black bounce solution, verifying its regularity, and putting forward that the spherical bouncing surface turns into an ellipsoid with no ring singularity. Finally, we find that increasing the LQG parameter leads to smaller ergospheres and reduced shadows, with potential implications for observational astrophysics and quantum gravitational signatures.
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Fortuna, F., Marquez, J. M., & Roig, P. (2025). HEFT approach to investigate the muon g-2 anomaly at a muon collider. Phys. Rev. D, 111(7), 075012–14pp.
Abstract: In a previous work, Buttazzo and Paradisi [Phys. Rev. D 104, 075021 (2021)], pointed out that heavy new physics (NP) contributions to lepton dipole moments and high-energy cross sections of lepton pairs into Higgs and gamma/Z bosons are connected, if the electroweak symmetry breaking is realized linearly. As a consequence, a multi-TeV muon collider would provide a unique test of NP in the muon g-2 through the study of high-energy processes such as mu+mu- -* h + gamma/Z. Since the analysis involved a Standard Model effective field theory (SMEFT) approach to Higgs processes, it could also be studied by the more general Higgs EFT (HEFT) formulation. We compute the modification of the high-energy cross section mu+mu- -* h + gamma/Z and h -* mu+mu- + gamma/Z decay using the dimension-6 HEFT Lagrangian and compare them with the SMEFT analysis. We find that, within the current HEFT analysis, there are plausible scenarios where the HEFT approach could lead to a higher sensitivity to test the NP contributions in the muon g-2. However, a more precise knowledge of the new HEFT parameters is needed for a definite conclusion, which motivates the search for complementary measurements.
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Oliver-Cañamas, L., Vijande, J., Candela-Juan, C., & Perez-Calatayud, J. (2025). Dosimetry audits in high dose rate brachytherapy: A survey on the current scenario in Europe. Phys. Medica, 136, 105047–7pp.
Abstract: Introduction: This work aims to study the current scenario of dosimetry audits in high dose rate (HDR) brachytherapy (BT) in Europe to evaluate whether there is a need to implement more services of this type and to define the characteristics that they should meet according to users. Material and methods: A survey consisting of 30 multiple choice questions was designed and distributed among European centers. The estimated time to answer was less than 15 min. 74 HDR BT centers participated, having 192Ir, 60Co and/or electronic sources. Information about users' opinions and experience with dosimetry audits in this field, center resources and quality assurance (QA) procedures was gathered. Results: For 61 % of users, dosimetry audits in HDR BT should be recommended, but not mandatory, whereas 35 % suggested that they are necessary and should be compulsory. Only for 4 % of participants these audits are not necessary. In contrast, 86 % of users found that the current number of these services is inadequate and that more national and/or international services are needed. Most participants operate according to QA recommendations of published guidelines, with exceptions, such as the use of the Reference Air Kerma Rate provided by the manufacturer instead of the one measured by the home medical physicist. Conclusion: The number of HDR BT dosimetry audits available to users is inadequate and there is a need to implement more national and/or international services of this type. Some technical aspects that an audit of this type should fulfill are outlined in this work.
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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). Search for Dark Matter Produced in Association with a Dark Higgs Boson in the b(b)over-bar Final State Using pp Collisions at √s=13 TeV with the ATLAS Detector. Phys. Rev. Lett., 134(12), 121801–24pp.
Abstract: A search is performed for dark matter particles produced in association with a resonantly produced pair of b-quarks with 30 < m(bb) < 150 GeV using 140 fb(-1) of proton-proton collisions at a center-of-mass energy of 13 TeV recorded by the ATLAS detector at the LHC. This signature is expected in extensions of the standard model predicting the production of dark matter particles, in particular those containing a dark Higgs boson s that decays into b (b) over bar. The highly boosted s -> b (b) over bar topology is reconstructed using jet reclustering and a new identification algorithm. This search places stringent constraints across regions of the dark Higgs model parameter space that satisfy the observed relic density, excluding dark Higgs bosons with masses between 30 and 150 GeV in benchmark scenarios with Z ' mediator masses up to 4.8 TeV at 95% confidence level.
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