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Related papers: Relaxing constraints on dark matter annihilation

200 papers

It was proposed that the massive compact halo objects (MCHOs) would be produced during an earlier epoch of cosmology if the density perturbations are between $3 \times 10^{-4}$ and 0.3. Then these objects can accrete dark matter particles…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-13 Yupeng Yang , Xiaoyuan Huang , Xuelei Chen , Hongshi Zong

Thermal dark matter that couples more strongly to electrons and photons than to neutrinos will heat the electron-photon plasma relative to the neutrino background if it becomes nonrelativistic after the neutrinos decouple from the thermal…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Chiu Man Ho , Robert J. Scherrer

We calculate the limits on the fraction of viable dark matter minihalos in the early universe to host Population III.1 stars, surviving today as dark matter spikes in our Milky Way halo. Motivated by potential hints of light dark matter…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Pearl Sandick , Juerg Diemand , Katherine Freese , Douglas Spolyar

The first stars to form in the Universe may be powered by the annihilation of weakly interacting dark matter particles. These so-called dark stars, if observed, may give us a clue about the nature of dark matter. Here we examine which…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 P. Gondolo , Ji-Haeng Huh , Hyung Do Kim , S. Scopel

Ultracompact minihalos would be formed if there are larger density perturbations ($0.0003 < \delta\rho/\rho < 0.3$) in the earlier epoch. The density profile of them is steeper than the standard dark matter halos. If the dark matter can…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Yupeng Yang , Guilin Yang , Hongshi Zong

Dark Matter (DM) may be a thermal relic that annihilates into heavier states in the early Universe. This Forbidden DM framework accommodates a wide range of DM masses from keV to weak scales. An exponential hierarchy between the DM mass and…

High Energy Physics - Phenomenology · Physics 2015-08-13 Raffaele Tito D'Agnolo , Joshua T. Ruderman

If moduli, or other long-lived heavy states, decay in the early universe in part into light and feebly interacting particles (such as axions), these decay products could account for the additional energy density in radiation that is…

High Energy Physics - Phenomenology · Physics 2013-10-30 Dan Hooper

We propose that dark matter is dominantly comprised of atomic bound states. We build a simple model and map the parameter space that results in the early universe formation of hydrogen-like dark atoms. We find that atomic dark matter has…

High Energy Physics - Phenomenology · Physics 2015-05-14 David E. Kaplan , Gordan Z. Krnjaic , Keith R. Rehermann , Christopher M. Wells

The Cold Dark Matter paradigm successfully explains many phenomena on scales larger than galaxies, but seems to predict galaxy halos which are more centrally concentrated and have a lumpier substructure than observed. Endowing cosmic dark…

Astrophysics · Physics 2007-05-23 Craig J. Hogan

Our ignorance of the period between the end of inflation and the beginning of Big Bang Nucleosynthesis limits our understanding of the origins and evolution of dark matter. One possibility is that the Universe's energy density was dominated…

High Energy Physics - Phenomenology · Physics 2017-09-08 Kayla Redmond , Adrienne L. Erickcek

In standard cosmology, the growth of structure becomes significant following matter-radiation equality. In non-thermal histories, where an effectively matter-dominated phase occurs due to scalar oscillations prior to Big Bang…

High Energy Physics - Phenomenology · Physics 2016-09-14 Adrienne L. Erickcek , Kuver Sinha , Scott Watson

The accumulation of dark matter particles near the primordial black holes starts at the radiation-dominated cosmological stage and produces the central density spikes. The spikes can be the bright gamma-ray sources due to dark matter…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-02 Yu. N. Eroshenko

We show that a nonstandard cosmological history with a period of early matter domination driven by a sub-TeV visible-sector particle can arise rather naturally. This scenario involves a long-lived standard model singlet that acquires a…

High Energy Physics - Phenomenology · Physics 2022-01-19 Rouzbeh Allahverdi , Jacek K. Osiński

We set an upper limit on the mass of a supersymmetric neutralino dark matter particle using the MicrOMEGAS and DarkSUSY software packages and the most recent constraints on relic density from combined WMAP and SDSS data. We explore several…

High Energy Physics - Phenomenology · Physics 2008-11-26 Rudy C. Gilmore

Atomic dark matter is usually considered to be produced asymmetrically in the early Universe. In this work, we first propose that the symmetric atomic dark matter can be thermally produced through the freeze-out mechanism. The dominant atom…

High Energy Physics - Phenomenology · Physics 2026-03-31 Yu-Cheng Qiu , Jie Sheng , Liang Tan , Chuan-Yang Xing

We argue that primordial dark matter halos could be generated during radiation domination by long range attractive forces stronger than gravity. In this paper we derive the conditions under which these structures could dominate the dark…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-17 Stefano Savastano , Luca Amendola , Javier Rubio , Christof Wetterich

What is the upper limit of the mass of the neutralino dark matter whose thermal relic is consistent with the observation? If the neutralino dark matter and colored sparticles are extremely degenerated in mass, with a mass difference less…

High Energy Physics - Phenomenology · Physics 2020-01-07 Hajime Fukuda , Feng Luo , Satoshi Shirai

The first stars in the universe form inside $\sim 10^6 M_\odot$ dark matter (DM) haloes whose initial density profiles are laid down by gravitational collapse in hierarchical structure formation scenarios. During the formation of the first…

Astrophysics · Physics 2011-02-11 Katherine Freese , Paolo Gondolo , J. A. Sellwood , Douglas Spolyar

Although it is commonly assumed that relativistic particles dominate the energy density of the universe quickly after inflation, a variety of well-motivated scenarios predict an early matter-dominated era (EMDE) before the onset of Big Bang…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-12 Hwan Bae , Adrienne L. Erickcek , M. Sten Delos , Julian B. Muñoz

We show that hidden hot dark matter, hidden-sector dark matter with interactions that decouple when it is relativistic, is a viable dark matter candidate provided it has never been in thermal equilibrium with the particles of the standard…

Cosmology and Nongalactic Astrophysics · Physics 2009-12-15 Kris Sigurdson