Article
Astronomy & Astrophysics
Anibal D. Medina, Nicolas I. Mileo, Alejandro Szynkman, Santiago A. Tanco
Summary: The study focuses on the weakly interacting massive particle (WIMP) paradigm and investigates a specific Dirac fermion candidate for dark matter. The research finds that there are still unexplored regions in the parameter space and collider experiments may improve the current constraints. However, detecting the anomalous interactions between the Z' and the electroweak gauge bosons proves to be extremely challenging.
Article
Astronomy & Astrophysics
Giorgio Arcadi, Andreas Bally, Florian Goertz, Karla Tame-Narvaez, Valentin Tenorth, Stefan Vogl
Summary: The study suggests that the XENON1T electron recoil excess could be related to neutrino-electron interactions, while dark matter-electron scattering is less likely to lead to significant improvements. The parameter space is severely constrained, but potentially problematic bounds on electron couplings can be circumvented through a late phase transition in the new scalar sector.
Article
Astronomy & Astrophysics
Bastian Diaz Saez, Karim Ghorbani
Summary: In this study, a simple model with two singlet scalar dark matter candidates and a vector-like lepton was explored. The model can accommodate the correct dark matter relic abundance and the (g - 2)(mu) anomaly by having the masses of the three new fields around 100 GeV and the values of the minimum required couplings being order one, while evading collider and dark matter constraints.
Article
Astronomy & Astrophysics
S. N. Gninenko, N. Krasnikov
Summary: This study presents a model that explains the anomaly of muon g-2 and the relic density of dark matter. It suggests an interaction between dark matter and the Standard Model mediated by a portal boson called phi. The study also identifies similar events that support this interaction, which opens up new directions for future research.
Article
Physics, Multidisciplinary
Ian Holst, Dan Hooper, Gordan Krnjaic
Summary: This study suggests that the long-standing anomaly in muon g-2 may be explained by a new particle species that couples to dark matter and affects its annihilations in the early Universe. A comprehensive analysis of the model reveals a viable range of dark matter masses and predicts contributions that could potentially resolve the tension between early and late time measurements of the Hubble constant.
PHYSICAL REVIEW LETTERS
(2022)
Article
Astronomy & Astrophysics
Jun Guo, Zhaofeng Kang, Peng Zhang
Summary: This article presents a mechanism to evade the direct detection constraint on dark matter hypothesis. The mechanism involves a coupling between dark matter and a companion particle, and it exhibits characteristics of co-annihilation, especially in the TeV region.
Article
Astronomy & Astrophysics
Nobuchika Okada, Osamu Seto
Summary: The study suggests that superheavy WIMP dark matters with mass greater than or equal to 10(9) GeV are still viable even if null results are obtained from direct DM searches. Additionally, a suitable reheating temperature can reproduce the observed abundance for superheavy WIMP dark matters.
Article
Physics, Particles & Fields
Salvatore Bottaro, Dario Buttazzo, Marco Costa, Roberto Franceschini, Paolo Panci, Diego Redigolo, Ludovico Vittorio
Summary: This study focuses on studying scenarios where Dark Matter is a weakly interacting particle embedded in an Electro Weak multiplet. Calculations are done for both scalar and fermionic WIMPs, including effects like Sommerfeld enhancement and bound states formation. The study also outlines strategies to probe these scenarios at future experiments, including high energy muon colliders and gamma-ray telescopes.
EUROPEAN PHYSICAL JOURNAL C
(2022)
Article
Astronomy & Astrophysics
J. A. Aguilar-Saavedra, D. E. Lopez-Fogliani, C. Munoz, M. Pierre
Summary: The study introduces the U mu nu SSM model as an extension of the mu nu SSM supersymmetric model, where violating baryon-number operators and explicit mass terms are prohibited. The research also analyzes the relic density of the dark matter candidate by calculating through Z', Higgs-right sneutrino, and dark matter mediated annihilations, as well as assessing potential signals in dark matter direct detection experiments.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Andrei E. Egorov
Summary: This study derived robust constraints on annihilating weakly interacting massive particle (WIMP) parameters based on new radio observations and dark matter distribution studies of M31. The obtained constraints exclude thermal WIMPs with lighter masses for specific annihilation channels and provide competitive results compared to other observations. The study also suggests that the explanation of the gamma-ray outer halo of M31 and the Galactic Center excess by annihilating dark matter is not excluded. The results indicate that a thermal WIMP with a mass of approximately 70 GeV could contribute significantly to nonthermal radio flux in M31 nucleus.
Article
Astronomy & Astrophysics
Shao-Ping Li
Summary: We find that in thermal plasma, scattering and decay can have the same order of couplings. This is contrary to the common belief that scattering is suppressed compared to decay. We provide an example of freeze-in production of heavy dark matter to illustrate this point. The relative contributions of scattering and decay depend on the thermal coupling strength.
Article
Astronomy & Astrophysics
Kento Asai, Coh Miyao, Shohei Okawa, Koji Tsumura
Summary: This study investigates a renormalizable scalar singlet dark matter model based on Z4 lepton flavor symmetry, with the introduction of a mu tau-philic scalar doublet as a mediator connecting dark matter and standard model particles. The flavor off-diagonal interactions of scalar mediators help to easily maintain the observed relic abundance of dark matter and satisfy the current severe constraints from various experiments and observations. The possibility of dark matter direct detection through a one-loop process is also explored, and it is found that the relic abundance of dark matter and the discrepancy of the muon anomalous magnetic moment can be explained simultaneously by the mu tau-philic scalar mediator.
Article
Astronomy & Astrophysics
Ernest Ma
Summary: According to the proposal, lepton number is considered as the result of a spontaneously broken non-Abelian gauge SU(2)(N) symmetry. New fermions are added to support this new symmetry, with their spontaneous breaking allowing them to be part of the dark sector, potentially contributing significantly to the muon anomalous magnetic moment.
Article
Astronomy & Astrophysics
Ernest Ma
Summary: The study shows that in a simple extension of the standard model, lepton number is elevated to a U(1)(L) gauge symmetry while preserving a conserved Z(3)(L) lepton symmetry, allowing for naturally small masses to be acquired from a previously proposed mechanism. Dark matter is described as a singlet scalar, with its dark symmetry derivable from Z(3)(L) and suggesting a possible explanation for the muon's g - 2 value.
Article
Astronomy & Astrophysics
Debasish Borah, Suruj Jyoti Das, Abhijit Kumar Saha, Rome Samanta
Summary: We propose a novel method to detect weakly interacting massive particle (WIMP) dark matter candidates that fall short of satisfying correct thermal relic abundance. Late entropy dilution is used to bring the overproduced relic within observed limits, while generating peculiar spectral shapes of gravitational waves (GWs) resulting from cosmic strings formed due to symmetry breaking. The correlation between DM mass and turning frequency of the GW spectrum provides potential for future experiments.
Article
Astronomy & Astrophysics
Nelson R. F. Braga, Octavio C. Junqueira
Summary: This study investigates the influence of rotation on the transition temperature of strongly interacting matter produced in non-central heavy ion collisions. By using a holographic description of an AdS black hole, the authors extend the analysis to the more realistic case where the matter spreads over a region around the rotational axis. The results show the coexistence of confined and deconfined phases and are consistent with the concept of local temperature in rotating frames developed by Tolman and Ehrenfest.
Article
Astronomy & Astrophysics
Bing Sun, Jiachen An, Zhoujian Cao
Summary: This paper investigates the effect of gravitational constant variation on the propagation of gravitational waves. By employing two analytical methods, the study finds that variations in the gravitational constant result in amplitude and phase corrections for gravitational waves, and the time variation of the gravitational constant can be constrained through the propagation of gravitational waves.
Article
Astronomy & Astrophysics
Abdellah Touati, Zaim Slimane
Summary: This letter presents the first study of Hawking radiation as a tunneling process within the framework of non-commutative gauge theory of gravity. The non-commutative Schwarzschild black hole is reconstructed using the Seiberg-Witten map and the star product. The emission spectrum of outgoing massless particles is computed using the quantum tunneling mechanism. The results reveal pure thermal radiation in the low-frequency scenario, but a deviation from pure thermal radiation in the high-frequency scenario due to energy conservation. It is also found that noncommutativity enhances the correlations between successively emitted particles.
Article
Astronomy & Astrophysics
Shahar Hod
Summary: The travel times of light signals between two antipodal points on a compact star's surface are calculated for two different trajectories. It is shown that, for highly dense stars, the longer trajectory along the surface may have a shorter travel time as measured by asymptotic observers. A critical value of the dimensionless density-area parameter is determined for constant density stars to distinguish cases where crossing through the star's center or following a semi-circular trajectory on the surface has a shorter travel time as measured by asymptotic observers.