相关论文: Boosting Assisted Annihilation for a Cosmologicall…
Assisted annihilation is a novel mechanism to generate viable sub-GeV thermal dark matter, where a pair of stable dark matter annihilates with an assister to Standard Model states. Typically such $3 \to 2$ annihilation topologies are flux…
In this paper we investigate light dark matter scenarios where annihilation to Standard Model particles at tree-level is kinematically forbidden. In such cases annihilation can be aided by massive Standard Model-like species, called {\it…
In some scenarios, the dark matter relic abundance is set by the semi-annihilation of two dark matter particles into one dark matter particle and one Standard Model particle. These semi-annihilations might still be occurring today in the…
The Breit-Wigner enhancement of the thermally averaged annihilation cross section <\sigma v> is shown to provide a large boost factor when the dark matter annihilation process nears a narrow resonance. We explicitly demonstrate the…
We consider a light scalar dark matter candidate with mass in the GeV range whose $p$-wave annihilation is enhanced through a Breit-Wigner resonance. The annihilation actually proceeds in the $s$-channel via a dark photon mediator whose…
Sub-MeV cold dark-matter particles are unable to produce electronic recoil in conventional dark-matter direct detection experiments such as XENONnT and LUX-ZEPLIN above the detector threshold. The mechanism of boosted dark matter comes into…
The evolution of the Universe between inflation and the onset of big bang nucleosynthesis is difficult to probe and largely unconstrained. This ignorance profoundly limits our understanding of dark matter: we cannot calculate its thermal…
In this letter, we consider a class of scenarios in which the dark matter is part of a heavy hidden sector that is thermally decoupled from the Standard Model in the early universe. The dark matter freezes-out by annihilating to a lighter,…
Recent observations from PAMELA, FERMI, and ATIC point to a new source of high energy cosmic rays. If these signals are due to annihilating dark matter, then the annihilation cross section in the present day must be substantially larger…
Producing an acceptable thermal relic abundance of dark matter with masses $\gg 10^2$ TeV is a challenge. We propose a novel mechanism where GeV-scale states establish a tiny thermal relic abundance for dark matter, which is later promoted…
Boosted dark matter constitutes a small fraction of the total dark matter in the Universe, with mass ranging from eV to MeV and often exhibiting (semi)relativistic velocity. Hence the likelihood of detecting boosted dark matter in…
Thermal relics lighter than an MeV contribute to the energy density of the universe at the time of nucleosynthesis and recombination. Constraints on extra radiation degrees of freedom typically exclude even the simplest of such dark…
Current multi-ton detectors put stringent constraints on the GeV-scale galactic dark matter, pushing the allowed cross-section almost towards the neutrino fog, yet remain mostly insensitive to the light dark matter. Cosmic rays can…
Thermal relic dark matter below $\sim 10 \ \text{GeV}$ is excluded by cosmic microwave background data if its annihilation to visible particles is unsuppressed near the epoch of recombination. Usual model-building measures to avoid this…
GeV-scale dark matter is an increasingly attractive target for direct detection, indirect detection, and collider searches. Especially for masses in the MeV to GeV range, indirect detection is expected to give a leading constraint. In that…
The recently introduced Sommerfeld enhancement of the dark matter annihilation cross section has important implications for the detection of dark matter annihilation in subhalos in the Galactic halo. In addition to the boost to the dark…
Anomalies in direct and indirect detection have motivated models of dark matter consisting of a multiplet of nearly-degenerate states, coupled by a new GeV-scale interaction. We perform a careful analysis of the thermal freezeout of dark…
Dark matter may be a thermal relic whose abundance is set by mutual annihilations among multiple species. Traditionally, this coannihilation scenario has been applied to weak scale dark matter that is highly degenerate with other states. We…
We study the phenomenology and detection prospects of a sub-GeV Dirac dark matter candidate with resonantly enhanced annihilations via a dark photon mediator. The model evades cosmological constraints on light thermal particles in the early…
We show that the event excess observed by the IceCube collaboration at TeV--PeV energies, usually interpreted as evidence for astrophysical neutrinos, can be explained alternatively by the scattering of highly boosted dark matter particles.…