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Alves, J. M. (2024). Controlling the flavour changing neutral couplings of multi-Higgs doublets models through unitary matrices. Eur. Phys. J. C, 84(9), 929–7pp.
Abstract: In this paper, we introduce unitary flavour violation to produce multi-Higgs doublets models where all flavour par ameters are contained within three unitary matrices. After that, we identify two of its subclasses, the left and right models, which have naturally suppressed tree-lev el flavour changing neutral couplings that easily avoid the experimental constraints derived from neutral meson mi xing. Then, we show that left models can accomodate spontaneous CP violation when all quarks have flavour changing neutr al couplings. Finally, we illustrate these concepts by considering a specific implementation with three Higgs doublets.
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Ureña, J., Sojo, A., Bermejo-Vega, J., & Manzano, D. (2024). Entanglement detection with classical deep neural networks. Sci Rep, 14(1), 18109–11pp.
Abstract: In this study, we introduce an autonomous method for addressing the detection and classification of quantum entanglement, a core element of quantum mechanics that has yet to be fully understood. We employ a multi-layer perceptron to effectively identify entanglement in both two- and three-qubit systems. Our technique yields impressive detection results, achieving nearly perfect accuracy for two-qubit systems and over 90% accuracy for three-qubit systems. Additionally, our approach successfully categorizes three-qubit entangled states into distinct groups with a success rate of up to 77%. These findings indicate the potential for our method to be applied to larger systems, paving the way for advancements in quantum information processing applications.
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Li, H. P., Song, J., Liang, W. H., Molina, R., & Oset, E. (2024). Contrasting observables related to the N*(1535) from the molecular or a genuine structure. Eur. Phys. J. C, 84(7), 656–8pp.
Abstract: In this work we compare the predictions for the scattering length and effective range of the channels K-0 Sigma(+), K+Sigma(0), K+ Lambda and eta p, assuming the N*(1535) state as a molecular state of these channels, or an original genuine state, made for instance from three quarks. Looking at very different scenarios, what we conclude is that the predictions of these two pictures are drastically different, to the point that we advise the measurement of these magnitudes, accessible for instance by measuring correlation functions, in order to gain much valuable information concerning the nature of this state.
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Heidari, N., Hassanabadi, H., Araujo Filho, A. A., & Kriz, J. (2024). Exploring non-commutativity as a perturbation in the Schwarzschild black hole: quasinormal modes, scattering, and shadows. Eur. Phys. J. C, 84(6), 566–11pp.
Abstract: In this work, by a novel approach to studying the scattering of a Schwarzschild black hole, the non-commutativity is introduced as perturbation. We begin by reformulating the Klein-Gordon equation for the scalar field in a new form that takes into account the deformed non-commutative spacetime. Using this formulation, an effective potential for the scattering process is derived. To calculate the quasinormal modes, we employ the WKB method and also utilize fitting techniques to investigate the impact of non-commutativity on the scalar quasinormal modes. We thoroughly analyze the results obtained from these different methods. Moreover, the greybody factor and absorption cross section are investigated. Additionally, we explore the behavior of null geodesics in the presence of non-commutativity. Specifically, we examine the photonic, and shadow radius as well as the light trajectories for different non-commutative parameters. Therefore, by addressing these various aspects, we aim to provide a comprehensive understanding of the influence of non-commutativity on the scattering of a Schwarzschild-like black hole and its implications for the behavior of scalar fields and light trajectories.
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Silva, J. E. G., Yesiltas, O., Furtado, J., & Araujo Filho, A. A. (2024). Strain effects on the electronic properties of a graphene wormhole. Eur. Phys. J. Plus, 139(8), 762–16pp.
Abstract: In this work, we explore the strain and curvature effects on the electronic properties of a curved graphene structure, called the graphene wormhole. The electron dynamics is described by a massless Dirac fermion containing position-dependent Fermi velocity. In addition, the strain produces a pseudo-magnetic vector potential to the geometric coupling. For an isotropic strain tensor, the decoupled components of the spinor field exhibit a supersymmetric (SUSY) potential, depending on the centrifugal term and the external magnetic field only. In the absence of an external magnetic field, the strain yields an exponentially damped amplitude, whereas the curvature leads to a power-law damping of the wave function. The spin-curvature coupling breaks the chiral symmetry between the upper and the lower spinor component, which leads to the increasing of the wave function on either upper or lower region of the wormhole, i.e., depending on the spin number. By adding a uniform magnetic field, the effective potential exhibits an asymptotic quadratic profile and a spin-curvature barrier near the throat. As a result, the bound states (Landau levels) are confined around the wormhole throat showing an asymmetric and spin-dependent profile.
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Belen Galan, M., Alvarez-Ruso, L., Rafi Alam, M., Ruiz Simo, I., & Vicente Vacas, M. J. (2024). Cabibbo suppressed hyperon production off nuclei induced by antineutrinos. Phys. Rev. D, 109(3), 033001–13pp.
Abstract: In this work, we study the production of E and A hyperons in strangeness -changing AS = -1 chargedcurrent interactions of muon antineutrinos on nuclear targets. At the nucleon level, besides quasielastic scattering, we consider the inelastic mechanism in which a pion is produced alongside the hyperon. Its relevance for antineutrinos with energies below 2 GeV is conveyed in integrated and differential cross sections. We observe that the distributions on the angle between the hyperon and the final lepton are clearly different for quasielastic and inelastic processes. Hyperon final -state interactions, modeled with an intranuclear cascade, lead to a significant transfer from primary produced E's into final A's. They also cause considerable energy loss, which is apparent in hyperon energy distributions. We have investigated A production off 40Ar in the conditions of the recently reported MicroBooNE measurement. We find that the A pi contribution, dominated by E*(1385) excitation, accounts for about one third of the cross section.
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Yeung, T. T. et al, Morales, A. I., Tain, J. L., Alcala, G., Algora, A., Agramunt, J., et al. (2024). First Exploration of Monopole-Driven Shell Evolution above the N=126 Shell Closure: New Millisecond Isomers in Tl-213 and Tl-215. Phys. Rev. Lett., 133(7), 072501–7pp.
Abstract: Isomer spectroscopy of heavy neutron-rich nuclei beyond the N = 126 closed shell has been performed for the first time at the Radioactive Isotope Beam Factory of the RIKEN Nishina Center. New millisecond isomers have been identified at low excitation energies, 985.3(19) keV in Tl-213 and 874(5) keV in Tl-215. The measured half-lives of 1.34(5) ms in Tl-213 and 3.0(3) ms in Tl-215 suggest spins and parities 11/2(-) with the single proton-hole configuration pi h(11/2) as leading component. They are populated via E1 transitions by the decay of higher-lying isomeric states with proposed spin and parity 17/2(+), interpreted as arising from a single pi s(1/2) proton hole coupled to the 8(+) seniority isomer in the PbA + 1 cores. The lowering of the 11/2(-) states is ascribed to an increase of the pi h(11/2) proton effective single-particle energy as the second nu g(9/2) orbital is filled by neutrons, owing to a significant reduction of the proton-neutron monopole interaction between the pi h(11/2) and nu g(9/2) orbitals. The new ms isomers provide the first experimental observation of shell evolution in the almost unexplored N > 126 nuclear region below doubly magic Pb-208.
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Anzivino, G. et al, Gonzalez-Alonso, M., Passemar, E., & Pich, A. (2024). Workshop summary: Kaons@CERN 2023. Eur. Phys. J. C, 84(4), 377–34pp.
Abstract: Kaon physics is at a turning point – while the rare-kaon experiments NA62 and KOTO are in full swing, the end of their lifetime is approaching and the future experimental landscape needs to be defined. With HIKE, KOTO-II and LHCb-Phase-II on the table and under scrutiny, it is a very good moment in time to take stock and contemplate about the opportunities these experiments and theoretical developments provide for particle physics in the coming decade and beyond. This paper provides a compact summary of talks and discussions from the Kaons@CERN 2023 workshop, held in September 2023 at CERN.
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De Romeri, V., Martin Lozano, V., & Sanchez Garcia, G. (2024). Neutrino window to scalar leptoquarks: From low energy to colliders. Phys. Rev. D, 109(5), 055014–21pp.
Abstract: Leptoquarks are theorized particles of either scalar or vector nature that couple simultaneously to quarks and leptons. Motivated by recent measurements of coherent elastic neutrino -nucleus scattering, we consider the impact of scalar leptoquarks coupling to neutrinos on a few complementary processes, from low energy to colliders. In particular, we set competitive constraints on the typical mass and coupling of scalar leptoquarks by analyzing recent COHERENT data. We compare these constraints with bounds from atomic parity violation experiments, deep inelastic neutrino -nucleon scattering and collider data. Our results highlight a strong complementarity between different facilities and demonstrate the power of coherent elastic neutrino -nucleus scattering experiments to probe leptoquark masses in the sub-TeV range. Finally, we also present prospects for improving current bounds with future upgrades of the COHERENT detectors and the planned European Spallation Source.
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Das, B. et al, & Algora, A. (2024). Broken seniority symmetry in the semimagic proton mid-shell nucleus 95Rh. Phys. Rev. Res., 6(2), L022038–7pp.
Abstract: Lifetime measurements of low-lying excited states in the semimagic ( N = 50) nucleus 95 Rh have been performed by means of the fast -timing technique. The experiment was carried out using gamma -ray detector arrays consisting of LaBr 3 (Ce) scintillators and germanium detectors integrated into the DESPEC experimental setup commissioned for the Facility for Antiproton and Ion Research ( FAIR ) Phase -0, Darmstadt, Germany. The excited states in 95 Rh were populated primarily via the /3 decays of 95 Pd nuclei, produced in the projectile fragmentation of a 850 MeV / nucleon 124 Xe beam impinging on a 4 g / cm 2 9 Be target. The deduced electromagnetic E2 transition strengths for the gamma -ray cascade within the multiplet structure depopulating from the isomeric I pi = 21 / 2 + state are found to exhibit strong deviations from predictions of standard shell model calculations which feature approximately conserved seniority symmetry. In particular, the observation of a strongly suppressed E2 strength for the 13 / 2 + -> 9 / 2 + ground state transition cannot be explained by calculations employing standard interactions. This remarkable result may require revision of the nucleon-nucleon interactions employed in state-of-the-art theoretical model calculations, and might also point to the need for including three-body forces in the Hamiltonian.
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