Bhattacharya, S., Mondal, N., Roshan, R., & Vatsyayan, D. (2024). Leptogenesis, dark matter and gravitational waves from discrete symmetry breaking. J. Cosmol. Astropart. Phys., 06(6), 029–25pp.
Abstract: We analyse a model that connects the neutrino sector and the dark sector of the universe via a mediator 41., stabilised by a discrete Z4 symmetry that breaks to a remnant Z2 upon 41. acquiring a non -zero vacuum expectation value (v phi). The model accounts for the observed baryon asymmetry of the universe via additional contributions to the canonical Type -I leptogenesis. The Z4 symmetry breaking scale (v phi) in the model not only establishes a connection between the neutrino sector and the dark sector, but could also lead to gravitational wave signals that are within the reach of current and future experimental sensitivities.
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Montesinos, V., Albaladejo, M., Nieves, J., & Tolos, L. (2024). Charge-conjugation asymmetry and molecular content: The Ds0*(2317)± in matter. Phys. Lett. B, 853, 138656–10pp.
Abstract: We analyze the modifications that a dense nuclear medium induces in the D-s0*(2317)(+/-) and D-s1(2460)(+/-). In the vacuum, we consider them as isoscalar D-(*K-) and (D) over bar (()*())(K) over bar S-wave bound states, which are dynamically generated from effective interactions that lead to different Weinberg compositeness scenarios. Matter effects are incorporated through the two-meson loop functions, taking into account the self energies that the D-(*()), (D) over bar (()*()), K, and (K) over bar develop when embedded in a nuclear medium. Although particle-antiparticle [D-s0,s1(()*())(2317,2460)(+) versus D-s0,s1(()*())(2317,2460)(-)] lineshapes are the same in vacuum, we find extremely different density patterns in matter. This charge-conjugation asymmetry mainly stems from the very different kaon and antikaon interaction with the nucleons of the dense medium. We show that the in-medium lineshapes found for these resonances strongly depend on their D-(*()), K/(D) over bar (()*()), K molecular content, and discuss how this novel feature can be used to better determine/constrain the inner structure of these exotic states.
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Roca, L., Song, J., & Oset, E. (2024). Molecular pentaquarks with hidden charm and double strangeness. Phys. Rev. D, 109(9), 094005–8pp.
Abstract: We analyze theoretically the coupled-channel meson-baryon interaction with global flavor c<overline>cssn and c<overline>csss, where mesons are pseudoscalars or vectors, and baryons have JP = 1/2+ or 3/2+. The aim is to explore whether the nonlinear dynamics inherent in the unitarization process within coupled channels can dynamically generate double- and triple-strange pentaquark-type states (Pcss and Pcsss, respectively), for which there is no experimental evidence to date. We evaluate the s-wave scattering matrix by implementing unitarity in coupled channels, using potential kernels obtained from t-channel vector meson exchange. The required PPV and VVV vertices are obtained from Lagrangians derived through appropriate extensions of the local hidden gauge symmetry approach to the charm sector, while capitalizing on the symmetry of the spin and flavor wave function to evaluate the BBV vertex. We find four different poles in the double strange sector, some of them degenerate in spin. For the triple-strange channel, we find the meson-baryon interaction insufficient to generate a bound or resonance state through the unitary coupled-channel dynamics.
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Balbinot, R., & Fabbri, A. (2023). Quantum energy momentum tensor and equal time correlations in a Reissner-Nordström black hole. Phys. Rev. D, 108, 045004–9pp.
Abstract: We consider a Reissner-Nordström black hole formed by the collapse of a charged null shell. The renormalized expectation values of the energy-momentum tensor operator for a massless scalar field propagating in the two-dimensional section of this spacetime are given. We then analyze the across-the-horizon correlations of the related energy density operator for free-falling observers to reveal the correlations between the Hawking particles and their interior partners.
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Nascimento, J. R., Olmo, G. J., Petrov, A. Y., & Porfirio, P. J. (2024). On metric-affine bumblebee model coupled to scalar matter. Nucl. Phys. B, 1004, 116577–10pp.
Abstract: We consider the coupling of the metric-affine bumblebee gravity model to scalar matter and calculate the lower -order contributions to two -point functions of bumblebee and scalar fields in the weak gravity approximation. We also obtain the one -loop effective potentials for both scalar and vector fields.
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Gil-Dominguez, F., & Molina, R. (2024). Quark mass dependence of the D*s0 (2317) and D s1 (2460) resonances. Phys. Rev. D, 109(9), 096002–17pp.
Abstract: We determine the quark mass dependence-light and heavy-of the D*s0(2317) and Ds1(2460) properties, such as, mass, coupling to D(*)K, scattering lengths and compositeness, from a global analysis I = 0 for different boosts and two pion masses. The formalism is based in the local hidden-gauge interaction of Weinberg-Tomozawa type which respects both chiral and heavy quark spin symmetries, supplemented by a term that takes into account the D(*)K coupling to a bare cs<overline> component. The isospin violating decay of the D*s0(2317) -> D+s pi 0 is also evaluated.
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Easa, H., Gregoire, T., Stolarski, D., & Cosme, C. (2024). Baryogenesis and dark matter in multiple hidden sectors. Phys. Rev. D, 109(7), 075003–29pp.
Abstract: We explore a mechanism for producing the baryon asymmetry and dark matter in models with multiple hidden sectors that are Standard -Model -like but with varying Higgs mass parameters. If the field responsible for reheating the Standard Model and the exotic sectors carries an asymmetry, it can be converted into a baryon asymmetry using the standard sphaleron process. A hidden sector with positive Higgs mass squared can accommodate dark matter with its baryon asymmetry, and the larger abundance of dark matter relative to baryons is due to dark sphalerons being active all the way down the hidden sector QCD scale. This scenario predicts that dark matter is clustered in large dark nuclei and gives a lower bound on the effective relativistic degrees of freedom, Delta N eff greater than or similar to 0 .05 , which may be observable in the nextgeneration cosmic microwave background experiment CMB-S4.
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del Rio, A., & Ester, E. A. (2024). Electrically charged black hole solutions in semiclassical gravity and dynamics of linear perturbations. Phys. Rev. D, 109(10), 105022–23pp.
Abstract: We explore quantum corrections of electrically charged black holes subject to vacuum polarization effects of fermion fields in QED. Solving this problem exactly is challenging so we restrict to perturbative corrections that one can obtain using the heat kernel expansion in the one -loop effective action for electrons. Starting from the corrections originally computed by Drummond and Hathrell, we solve the full semiclassical Einstein -Maxwell system of coupled equations to leading order in Planck 's constant and find a new electrically charged, static black hole solution. To probe these quantum corrections, we study electromagnetic and gravitational (axial) perturbations on this background and derive the coupled system of Regge-Wheeler master equations that govern the propagation of these waves. In the classical limit, our results agree with previous findings in the literature. We finally compare these results with those that one can obtain by working out the Euler-Heisenberg effective action. We find again a new electrically charged static black hole spacetime and derive the coupled system of Regge-Wheeler equations governing the propagation of axial electromagnetic and gravitational perturbations. Results are qualitatively similar in both cases. We briefly discuss some challenges found in the numerical computation of the quasinormal mode frequency spectra when quantum corrections are included.
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Servant, G., & Simakachorn, P. (2024). Ultrahigh frequency primordial gravitational waves beyond the kHz: The case of cosmic strings. Phys. Rev. D, 109(10), 103538–24pp.
Abstract: We investigate gravitational -wave backgrounds (GWBs) of primordial origin that would manifest only at ultrahigh frequencies, from kilohertz to 100 gigahertz, and leave no signal at LIGO, the Einstein Telescope, the Cosmic Explorer, LISA, or pulsar -timing arrays. We focus on GWBs produced by cosmic strings and make predictions for the GW spectra scanning over high-energy scale (beyond 10 10 GeV) particle physics parameters. Signals from local string networks can easily be as large as the big bang nucleosynthesis/ cosmic microwave background bounds, with a characteristic strain as high as 10 – 26 in the 10 kHz band, offering prospects to probe grand unification physics in the 10 14 -10 17 GeV energy range. In comparison, GWB from axionic strings is suppressed (with maximal characteristic strain similar to 10 – 31 ) due to the early matter era induced by the associated heavy axions. We estimate the needed reach of hypothetical futuristic GW detectors to probe such GWB and, therefore, the corresponding high-energy physics processes. Beyond the information of the symmetry -breaking scale, the high -frequency spectrum encodes the microscopic structure of the strings through the position of the UV cutoffs associated with cusps and kinks, as well as potential information about friction forces on the string. The IR slope, on the other hand, reflects the physics responsible for the decay of the string network. We discuss possible strategies for reconstructing the scalar potential, particularly the scalar self -coupling, from the measurement of the UV cutoff of the GW spectrum.
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Barenboim, G., Calatayud-Cadenillas, A. M., Gago, A. M., & Ternes, C. A. (2024). Quantum decoherence effects on precision measurements at DUNE and T2HK. Phys. Lett. B, 852, 138626–11pp.
Abstract: We investigate the potential impact of neutrino quantum decoherence on the precision measurements of standard neutrino oscillation parameters in the DUNE and T2HK experiments. We show that the measurement of delta(CP), sin(2) theta(13) and sin(2) theta(23) is stronger effected in DUNE than in T2HK. On the other hand, DUNE would have a better sensitivity than T2HK to observe decoherence effects. By performing a combined analysis of DUNE and T2HK we show that a robust measurement of standard parameters would be possible, which is not guaranteed with DUNE data alone.
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