Balbinot, R., & Fabbri, A. (2023). The Hawking Effect in the Particles-Partners Correlations. Physics, 5(4), 968–982.
Abstract: We analyze the correlations functions across the horizon in Hawking black hole radiation to reveal the correlations between Hawking particles and their partners. The effects of the underlying space-time on this are shown in various examples ranging from acoustic black holes to regular black holes.
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Amerio, A., Calore, F., Serpico, P. D., & Zaldivar, B. (2024). Deepening gamma-ray point-source catalogues with sub-threshold information. J. Cosmol. Astropart. Phys., 03(3), 055–18pp.
Abstract: We propose a novel statistical method to extend Fermi-LAT catalogues of highlatitude -y-ray sources below their nominal threshold. To do so, we rely on the determination of the differential source -count distribution of sub -threshold sources which only provides the statistical flux distribution of faint sources. By simulating ensembles of synthetic skies, we assess quantitatively the likelihood for pixels in the sky with relatively low -test statistics to be due to sources, therefore complementing the source -count distribution with spatial information. Besides being useful to orient efforts towards multi -messenger and multi -wavelength identification of new -y-ray sources, we expect the results to be especially advantageous for statistical applications such as cross -correlation analyses.
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Chakraborty, S., Gupta, A., & Vanvlasselaer, M. (2023). Anomaly induced cooling of neutron stars: a Standard Model contribution. J. Cosmol. Astropart. Phys., 10(10), 030–23pp.
Abstract: Young neutron stars cool via the emission of neutrinos from their core. A precise understanding of all the different processes producing neutrinos in the hot and degenerate matter is essential for assessing the cooling rate of such stars. The main Standard Model processes contributing to this effect are nu bremsstrahlung, mURCA among others. In this paper, we investigate another Standard Model process initiated by the Wess-Zumino-Witten term, leading to the emission of neutrino pairs via N gamma -> N nu nu over bar . We find that for proto-neutron stars, such processes with degenerate neutrons can be comparable and even dominate over the typical and well-known cooling mechanisms.
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Adolf, P., Hirsch, M., & Päs, H. (2023). Radiative neutrino masses and the Cohen-Kaplan-Nelson bound. J. High Energy Phys., 11(11), 078–14pp.
Abstract: Recently, an increasing interest in UV/IR mixing phenomena has drawn attention to the range of validity of standard quantum field theory. Here we explore the consequences of such a limited range of validity in the context of radiative models for neutrino mass generation. We adopt an argument first published by Cohen, Kaplan and Nelson that gravity implies both UV and IR cutoffs, apply it to the loop integrals describing radiative corrections, and demonstrate that this effect has significant consequences for the parameter space of radiative neutrino mass models.
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De Romeri, V., Giunti, C., Stuttard, T., & Ternes, C. A. (2023). Neutrino oscillation bounds on quantum decoherence. J. High Energy Phys., 09(9), 097–24pp.
Abstract: We consider quantum-decoherence effects in neutrino oscillation data. Working in the open quantum system framework we adopt a phenomenological approach that allows to parameterize the energy dependence of the decoherence effects. We consider several phenomenological models. We analyze data from the reactor experiments RENO, Daya Bay and KamLAND and from the accelerator experiments NOvA, MINOS/MINOS+ and T2K. We obtain updated constraints on the decoherence parameters quantifying the strength of damping effects, which can be as low as Gamma ij less than or similar to 8 x 10-27 GeV at 90% confidence level in some cases. We also present sensitivities for the future facilities DUNE and JUNO.
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Beltran, R., Cepedello, R., & Hirsch, M. (2023). Tree-level UV completions for NRSMEFT d=6 and d=7 operators. J. High Energy Phys., 08(8), 31pp.
Abstract: We study ultra-violet completions for operators in standard model effective field theory extended with right-handed neutrinos (NRSMEFT). Using a diagrammatic method, we generate systematically lists of possible tree-level completions involving scalars, fermions or vectors for all operators at d = 6 and d = 7, which contain at least one right-handed neutrino. We compare our lists of possible UV models to the ones found for pure SMEFT. We also discuss how the observation of LNV processes via NRSMEFT operators at the LHC can be related to Majorana neutrino masses of the standard model neutrinos.
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LHCb Collaboration(Aaij, R. et al), Jaimes Elles, S. J., Jashal, B. K., Martinez-Vidal, F., Oyanguren, A., Rebollo De Miguel, M., et al. (2023). Measurement of CP asymmetries and branching fraction ratios of B- decays to two charm mesons. J. High Energy Phys., 09(9), 202–30pp.
Abstract: The CP asymmetries of seven B- decays to two charm mesons are measured using data corresponding to an integrated luminosity of 9 fb(-1) of proton-proton collisions collected by the LHCb experiment. Decays involving a D*(0) or D-s(*-) meson are analysed by reconstructing only the D-0 or D-s(-) decay products. This paper presents the first measurement of A(CP) (B- -> D-s(*-) D-0) and A(CP) (B- -> D-s(-) D*(0)), and the most precise measurement of the other five CP asymmetries. There is no evidence of CP violation in any of the analysed decays. Additionally, two ratios between branching fractions of selected decays are measured.
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LHCb Collaboration(Aaij, R. et al), Jaimes Elles, S. J., Jashal, B. K., Martinez-Vidal, F., Oyanguren, A., Rebollo De Miguel, M., et al. (2023). Study of the Bose-Einstein correlations of same-sign pions in proton-lead collisions. J. High Energy Phys., 09(9), 172–29pp.
Abstract: Correlations of same-sign charged pions are analysed using proton-lead collision data collected by the LHCb experiment at a nucleon-nucleon centre-of-mass energy of 5.02TeV, corresponding to an integrated luminosity of 1.06 nb(-1). Bose-Einstein correlations are observed in the form of an enhancement of pair production for same-sign charged pions with a small four-momentum difference. The dependence of the correlation radius and the intercept parameter on the reconstructed charged-particle multiplicity is investigated. The measured correlation radii scale linearly with the cube root of the reconstructed charged-particle multiplicity, being compatible with predictions of hydrodynamic models on the collision system evolution.
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Dreiner, H. K., Koay, Y. S., Kohler, D., Martin Lozano, V., Montejo Berlingen, J., Nangia, S., et al. (2023). The ABC of RPV: classification of R-parity violating signatures at the LHC for small couplings. J. High Energy Phys., 07(7), 215–52pp.
Abstract: We perform a classification of all potential supersymmetric R-parity violating signatures at the LHC to address the question: are existing bounds on supersymmetric models robust, or are there still signatures not covered by existing searches, allowing LHCscale supersymmetry to be hiding? We analyze all possible scenarios with one dominant RPV trilinear coupling at a time, allowing for arbitrary LSPs and mass spectra. We consider direct production of the LSP, as well as production via gauge-cascades, and find 6 different experimental signatures for the LL <overline> E -case, 6 for the LQ <overline> D -case, and 5 for the <overline> U <overline> D <overline> D -case; together these provide complete coverage of the RPV-MSSM landscape. This set of signatures is confronted with the existing searches by ATLAS and CMS. We find all signatures have been covered at the LHC, although not at the sensitivity level needed to probe the direct production of all LSP types. For the case of a dominant LL <overline> E -operator, we use CheckMATE to quantify the current lower bounds on the supersymmetric masses and find the limits to be comparable to or better than the R-parity conserving case. Our treatment can be easily extended to scenarios with more than one non-zero RPV coupling.
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Domcke, V., Garcia-Cely, C., Lee, S. M., & Rodd, N. L. (2024). Symmetries and selection rules: optimising axion haloscopes for Gravitational Wave searches. J. High Energy Phys., 03(3), 128–51pp.
Abstract: In the presence of electromagnetic fields, both axions and gravitational waves (GWs) induce oscillating magnetic fields: a potentially detectable fingerprint of their presence. We demonstrate that the response is largely dictated by the symmetries of the instruments used to search for it. Focussing on low mass axion haloscopes, we derive selection rules that determine the parametric sensitivity of different detector geometries to axions and GWs, and which further reveal how to optimise the experimental geometry to maximise both signals. The formalism allows us to forecast the optimal sensitivity to GWs in the range of 100 kHz to 100 MHz for instruments such as ABRACADABRA, BASE, ADMX SLIC, SHAFT, WISPLC, and DMRadio.
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