Bordes, J., Chan, H. M., & Tsou, S. T. (2021). Unified FSM treatment of CP physics extended to hidden sector giving (i) delta(CP) for leptons as prediction, (ii) new hints on the material content of the universe. Int. J. Mod. Phys. A, 36, 2150238–19pp.
Abstract: A unified treatment of CP physics for quarks and leptons in the framed Standard Model (FSM) is extended to include the predicted hidden sector giving as consequences: (i) that an earlier part estimate of the Jarlskog invariant J' for leptons is turned into a prediction for its actual value, i.e. J' similar to -0.012 (delta(CP)' similar to 1.11 pi), which is of the right order of magnitude, of the right sign, and in the range of values favoured by the present experiment, (ii) some novel twists to the effects of CP-violation on the material content of the universe.
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Villanueva-Domingo, P., Mena, O., & Palomares-Ruiz, S. (2021). A Brief Review on Primordial Black Holes as Dark Matter. Front. Astron. Space Sci., 8, 681084–10pp.
Abstract: Primordial black holes (PBHs) represent a natural candidate for one of the components of the dark matter (DM) in the Universe. In this review, we shall discuss the basics of their formation, abundance and signatures. Some of their characteristic signals are examined, such as the emission of particles due to Hawking evaporation and the accretion of the surrounding matter, effects which could leave an impact in the evolution of the Universe and the formation of structures. The most relevant probes capable of constraining their masses and population are discussed.
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Araujo Filho, A. A., Jusufi, K., Cuadros-Melgar, B., & Leon, G. (2024). Dark matter signatures of black holes with Yukawa potential. Phys. Dark Universe, 44, 101500–20pp.
Abstract: This study uses a nonsingular Yukawa-modified potential to obtain a static and spherically symmetric black hole solution with a cosmological constant. Such Yukawa-like corrections are encoded in two parameters, alpha and lambda, that modify Newton's law of gravity in large distances, and a deformation parameter l(0), which plays an essential role in short distances. The most significant effect is encoded in alpha, which modifies the total black hole mass with an extra mass proportional to alpha M, mimicking the dark matter effects at large distances from the black hole. On the other hand, the effect due to lambda is small for astrophysical values. We scrutinize the quasinormal frequencies and shadows associated with a spherically symmetric black hole and the thermodynamical behavior influenced by the Yukawa potential. In particular, the thermodynamics of this black hole displays a rich behavior, including possible phase transitions. We use the WKB method to probe the quasinormal modes of massless scalar, electromagnetic, and gravitational field perturbations. In order to check the influence of the parameters on the shadow radius, we consider astrophysical data to determine their values, incorporating information on an optically thin radiating and infalling gas surrounding a black hole to model the black hole shadow image. In particular, we consider Sgr A* black hole as an example and we find that its shadow radius changes by order of 10(-9), meaning that the shadow radius of a black hole with Yukawa potential practically gives rise to the same result encountered in the Schwarzschild black hole. Also, in the eikonal regime, using astrophysical data for Yukawa parameters, we show that the value of the real part of the QNMs frequencies changes by 10(-18). Such Yukawa-like corrections are, therefore, difficult to measure by observations of gravitational waves using the current technology.
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Capozzi, F., Ferreira, R. Z., Lopez-Honorez, L., & Mena, O. (2023). CMB and Lyman-alpha constraints on dark matter decays to photons. J. Cosmol. Astropart. Phys., 06(6), 060–23pp.
Abstract: Dark matter energy injection in the early universe modifies both the ionization history and the temperature of the intergalactic medium. In this work, we improve the CMB bounds on sub-keV dark matter and extend previous bounds from Lyman-& alpha; observations to the same mass range, resulting in new and competitive constraints on axion-like particles (ALPs) decaying into two photons. The limits depend on the underlying reionization history, here accounted self-consistently by our modified version of the publicly available DarkHistory and CLASS codes. Future measurements such as the ones from the CMB-S4 experiment may play a crucial, leading role in the search for this type of light dark matter candidates.
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Bandyopadhyay, P., Chun, E. J., Mandal, R., & Queiroz, F. S. (2019). Scrutinizing right-handed neutrino portal dark matter with Yukawa effect. Phys. Lett. B, 788, 530–534.
Abstract: Analyzing the neutrino Yukawa effect in the freeze-out process of a generic dark matter candidate with right-handed neutrino portal, we identify the parameter regions satisfying the observed dark matter relic density as well as the current Fermi-LAT and H.E.S.S. limits and the future CTA reach on gamma-ray signals. In this scenario the dark matter couples to the Higgs boson at one-loop level and thus could be detected by spin-independent nucleonic scattering for a reasonable range of the relevant parameters.
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