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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…

宇宙学与河外天体物理 · 物理学 2013-05-30 Chiu Man Ho , Robert J. Scherrer

Light dark-matter ($M\leq20$ MeV) particles freeze out after neutrino decoupling. If the dark-matter particle couples to a neutrino or an electromagnetic plasma, the late time entropy production from dark-matter annihilation can change the…

高能天体物理现象 · 物理学 2016-03-14 Jae Ho Heo , C. S. Kim

Short baseline neutrino experiments such as LSND and MiniBooNE seem to suggest the existence of light sterile neutrinos. Meanwhile, current cosmic microwave background (CMB) and big bang nucleosynthesis (BBN) measurements place an upper…

高能物理 - 唯象学 · 物理学 2015-06-12 Chiu Man Ho , Robert J. Scherrer

We show that the new measurement of the effective number of neutrinos Neff by the Planck satellite can be used to set a robust lower bound on the mass of cold thermal dark matter of O(MeV). Our limit applies if the dark matter remains in…

高能物理 - 唯象学 · 物理学 2013-08-23 Celine Boehm , Matthew J. Dolan , Christopher McCabe

It is possible that the strongest interactions between dark matter and the Standard Model occur via the neutrino sector. Unlike gamma rays and charged particles, neutrinos provide a unique avenue to probe for astrophysical sources of dark…

According to conventional wisdom, in the standard model (SM) of particle physics and cosmology the effective number of neutrinos is Neff=3 (more precisely, 3.046). In extensions of the standard model allowing for the presence of DeltaNnu…

宇宙学与河外天体物理 · 物理学 2013-05-27 Gary Steigman

We discuss the lower limit on the mass of the neutralino $\chi$ that can be obtained by combining data from $e^+e^-$ annihilation at LEP and elsewhere with astrophysical and theoretical considerations. Loopholes in the purely experimental…

高能物理 - 唯象学 · 物理学 2009-09-11 John Ellis , Toby Falk , Keith Olive , Michael Schmitt

Current and most upcoming neutrino detectors can only reach a dark matter annihilation cross section to neutrinos larger than the standard freeze-out value, but they open intriguing detection avenues for non-standard dark matter paradigms.…

高能物理 - 唯象学 · 物理学 2025-08-06 Shinya Kanemura , Shao-Ping Li , Dibyendu Nanda

The Hawking evaporation of small black holes formed by the collapse of dark matter at the center of neutron stars plays a key role in loosing the constraint on the mass of asymmetric bosonic non-interacting dark matter particles. Different…

高能天体物理现象 · 物理学 2012-04-13 Yi-zhong Fan , Rui-zhi Yang , Jin Chang

A new U(1) gauge symmetry is the simplest extension of the Standard Model and has various theoretical and phenomenological motivations. In this paper, we study the cosmological constraint on the MeV scale dark photon. After the neutrino…

高能物理 - 唯象学 · 物理学 2020-09-30 Masahiro Ibe , Shin Kobayashi , Yuhei Nakayama , Satoshi Shirai

Observational limits on the high-energy neutrino background have been used to place general constraints on dark matter that annihilates only into standard model particles. Dark matter particles that annihilate into neutrinos will also…

高能物理 - 唯象学 · 物理学 2009-02-20 James B. Dent , Robert J. Scherrer , Thomas J. Weiler

We study an effective theory beyond the standard model (SM) where either of two additional gauge singlets, a Majorana fermion and a real scalar, constitutes all or some fraction of dark matter. In particular, we focus on the masses of the…

高能物理 - 唯象学 · 物理学 2019-05-22 Wen Yin

Effective field theory of dark matter fluid on large scales predicts the presence of viscosity of the order of $10^{-6} H_0 M_P^2$. It has been shown that this magnitude of viscosities can resolve the discordance between large scale…

宇宙学与河外天体物理 · 物理学 2018-05-23 Sampurn Anand , Prakrut Chaubal , Arindam Mazumdar , Subhendra Mohanty , Priyank Parashari

We present the first attempt to analytically study the nonlinear matter power spectrum for a mixed dark matter (cold dark matter plus neutrinos of total mass ~0.1eV) model based on cosmological perturbation theory. The suppression in the…

天体物理学 · 物理学 2009-06-23 Shun Saito , Masahiro Takada , Atsushi Taruya

We review the annihilation of dark matter into neutrinos over a range of dark matter masses from MeV$/c^2$ to ZeV$/c^2$. Thermally-produced models of dark matter are expected to self-annihilate to standard model products. As no such signal…

We propose a simple scenario that directly connects the dark matter (DM) and neutrino mass scales. Based on an interaction between the DM particle $\chi$ and the neutrino $\nu$ of the form $\chi\chi\nu\nu/\Lambda^2$, the DM annihilation…

高能物理 - 唯象学 · 物理学 2015-06-03 Wei-Chih Huang , Frank F. Deppisch

We study the effects of dark-matter annihilation during the epoch of big-bang nucleosynthesis on the primordial abundances of light elements. We improve the calculation of the light-element abundances by taking into account the effects of…

高能物理 - 唯象学 · 物理学 2015-10-28 Masahiro Kawasaki , Kazunori Kohri , Takeo Moroi , Yoshitaro Takaesu

We show that light ($\simeq$ 1 -- 30 MeV) dark matter particles can play a significant role in core-collapse supernovae, if they have relatively large annihilation and scattering cross sections, as compared to neutrinos. We find that if…

高能物理 - 唯象学 · 物理学 2008-11-26 Pierre Fayet , Dan Hooper , Gunter Sigl

It has been suggested that the annihilation of Dark Matter particles \chi with mass between 0.5 and 20 MeV into e^+e^- pairs could be responsible for the excess flux of 511 keV photons coming from the central region of our galaxy that has…

高能物理 - 唯象学 · 物理学 2008-11-26 Natalia Borodatchenkova , Debajyoti Choudhury , Manuel Drees

Massive neutrinos have a detectable effect on cosmological structure formation, in particular on the large-scale distribution of galaxies. Adding Hot Dark Matter to the now-standard Lambda CDM model leads to a worse fit to large-scale…

天体物理学 · 物理学 2007-05-23 Eric Gawiser
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