Article
Astronomy & Astrophysics
Ashadul Halder, Shibaji Banerjee, Madhurima Pandey, Debasish Majumdar
Summary: This study investigates the potential presence of dark matter and its self-annihilation in dwarf satellite galaxies of the Milky Way, calculating gamma-ray fluxes based on different dark matter models and comparing them with observational upper bounds reported by Fermi-LAT and Dark Energy Survey. Additionally, the analysis extends to the observational upper bounds for continuum gamma-ray fluxes from extragalactic sources given by Fermi-LAT.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Isabelle John, Tim Linden
Summary: This paper examines the potential for extremely precise positron measurements by AMS-02 to probe hard leptophilic dark matter candidates. The study finds no evidence for a spectral bump correlated with leptophilic dark matter and sets strong constraints on the dark matter annihilation cross-section.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
V. V. Flambaum, I. B. Samsonov
Summary: In the quark nugget model, the special role of antiquark nuggets leads to the study of positron clouds in dark matter. However, the strong electric field of antiquark nuggets significantly reduces the probability of electron-positron annihilation, which is insufficient to explain the observed photons in the center of our galaxy.
Article
Astronomy & Astrophysics
Pooja Bhattacharjee, Debajyoti Choudhury, Kasinath Das, Dilip Kumar Ghosh, Pratik Majumdar
Summary: This paper examines 14 recently discovered ultra-faint dwarf galaxies (UFDs) and studies the electromagnetic radiation emitted from them across a wide range of frequencies. Upper limits on annihilation cross section in a model independent way are obtained through analysis of Fermi-LAT data on high energy gamma rays and radio fluxes at the GMRT and VLA. The sensitivity of the Square Kilometer Array radio telescope in probing synchrotron radiation from the UFDs is discussed, as well as the dependence of the upper limits on uncertainties in determining various astrophysical parameters.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Nikita Blinov, Matthew J. Dolan, Patrick Draper, Jessie Shelton
Summary: This study introduces simplified models to explain enhancements in the matter power spectrum at small scales and investigates their impact on dark matter substructure and gravitational observables. The models capture the characteristics of various early Universe scenarios and discuss the sensitivity of gravitational observables to the presence of bumps in the power spectrum.
Article
Astronomy & Astrophysics
Katsuya Hashino, Jia Liu, Xiao-Ping Wang, Ke-Pan Xie
Summary: The study explores how cosmological evolution can alter dark matter properties and introduces a novel mechanism of transient dark matter annihilation, in line with existing dark matter detection results.
Article
Astronomy & Astrophysics
Nagisa Hiroshima, Kazunori Kohri, Toyokazu Sekiguchi, Ryuichi Takahashi
Summary: Constraints on annihilating dark matter are revisited based on the cosmological global 21 cm signature observed by EDGES. By estimating the boost factor at high redshifts and taking into account the energy injected from dark matter annihilation, the study excludes dark matter masses below 15 GeV and 3 GeV at 95% confidence level for certain modes in the thermal freeze-out scenario.
Article
Astronomy & Astrophysics
Ruth Durrer, Serge Parnovsky
Summary: In this paper, a new idea is proposed to explain the formation of galaxies through the infall of baryonic matter and dark matter onto preexisting overdensities. It is proposed that slow dark matter particles can be captured by increasing overdensities while faster particles transfer their energy to the galaxy. The capture rate of dark matter is found to be dependent on the density of intergalactic dark matter.
Article
Astronomy & Astrophysics
F. Calore, A. Dekker, P. D. Serpico, T. Siegert
Summary: Using the analysis method of INTEGRAL/SPI data and a dark matter spatial template, we investigate the constraints on dark matter candidates lighter than weakly interacting massive particles decaying into line or continuum electromagnetic final state channels. The obtained bounds are the strongest to date for dark matter masses between approximately 60 keV and 16 MeV, experiencing two-body decays producing photon lines.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Physics, Multidisciplinary
Antonio Ambrosone, Marco Chianese, Damiano F. G. Fiorillo, Antonio Marinelli, Gennaro Miele
Summary: Starburst galaxies are potential sources of high-energy gamma rays, and their cosmic-ray spectrum distortion can be indirectly observed. Current data provide tight bounds on the cross section between protons and dark matter, while future measurements are expected to significantly improve these limits.
PHYSICAL REVIEW LETTERS
(2023)
Article
Astronomy & Astrophysics
Jens Stucker, Go Ogiya, Simon D. M. White, Raul E. Angulo
Summary: Prompt cusps are dense objects of quasi-equilibrium dark matter that form at the instant of collapse within isolated peaks of the initial cosmological density field. They have power-law density profiles and contribute significantly to the annihilation luminosity of dark matter. Individual stellar encounters, rather than the mean galactic tide, are the primary disruptors of prompt cusps within galaxies. Stellar encounters suppress their mean annihilation luminosity, but this does not affect the Galactic center gamma-ray excess.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Turner Johnson, Andrew J. Benson, Daniel Grin
Summary: The study uses a random walk in halo energy space to predict the concentration of dark matter halos, calculates the total internal energy of each halo in a full merger tree, accurately reproduces the mean of the concentration-mass relation measured in N-body simulations, and replicates more of the scatter in that relation compared to previous models. The model closely matches N-body results in terms of auto-correlation of scale radii over time and correlations between halo concentration and spin.
ASTROPHYSICAL JOURNAL
(2021)
Article
Astronomy & Astrophysics
Marco Cirelli, Nicolao Fornengo, Bradley J. Kavanagh, Elena Pinetti
Summary: This study examines the potential of light dark matter with mass between 1 MeV and 1 GeV, comparing lower-energy x-ray data from the INTEGRAL telescope with predicted dark matter flux to derive competitive bounds. It includes the contribution from inverse Compton scattering on galactic radiation fields and the cosmic microwave background, leading to stronger constraints for dark matter masses above 20 MeV than previous studies.
Article
Astronomy & Astrophysics
Lucia Rinchiuso, Oscar Macias, Emmanuel Moulin, Nicholas L. Rodd, Tracy R. Slatyer
Summary: TeV-scale dark matter candidates, such as Wino and Higgsino, could potentially be detected by the upcoming Cherenkov Telescope Array (CTA) with significant sensitivity improvements over existing bounds. The study demonstrates the discovery potential for dark matter in the 1-100 TeV mass range with CTA's enhanced sensitivities.
Article
Astronomy & Astrophysics
Horst Foidl, Tanja Rindler-Daller
Summary: Scalar field dark matter (SFDM) is an alternative option to address the issues with traditional cold dark matter. This paper studies SFDM cosmologies by calculating the evolution of the background universe and the formation of linear perturbations. The results show differences in the background evolution and structure growth between models with complex scalar field and models with a complex field.
