Related papers: Exponentially Light Dark Matter from Coannihilatio…
The cosmological evolution can modify the dark matter (DM) properties in the early Universe to be vastly different from the properties today. Therefore, the relation between the relic abundance and the DM constraints today needs to be…
The semi-annihilation reaction takes the schematic form psi_i psi_j -> psi_k phi, where psi_i are stable dark matter particles and phi is an unstable state. Such reactions are allowed when dark matter is stabilized by a larger symmetry than…
Progress in observational cosmology over the past five years has established that the Universe is dominated dynamically by dark matter and dark energy. Both these new and apparently independent forms of matter-energy have properties that…
Feebly interacting thermal relics are promising dark matter candidates. Among them, scenarios of inelastic Dark Matter evade direct detection by suppressed elastic scattering off atomic nuclei. We introduce inelastic Dirac Dark Matter, a…
Recently it was shown that dark matter with mass of order the weak scale can be charged under a new long-range force, decoupled from the Standard Model, with only weak constraints from early Universe cosmology. Here we consider the…
We consider dark matter models in which the mass splitting between the dark matter particles and their annihilation products is tiny. Compared to the previously proposed Forbidden Dark Matter scenario, the mass splittings we consider are…
Thermal freeze-out is a prominent example of dark matter (DM) production mechanism in the early Universe that can yield the correct relic density of stable weakly interacting massive particles (WIMPs). At the other end of the mass scale,…
The Universe's early thermal history is poorly constrained, and it is possible that it underwent a period of early matter domination driven by a heavy particle or an oscillating scalar field that decayed into radiation before the onset of…
We point out a selection rule for enhancement (suppression) of odd (even) partial waves of dark matter coannihilation or annihilation using Sommerfeld effect. Using this, the usually velocity-suppressed p-wave annihilation can dominate the…
In the past decade, gamma-ray observations and radio observations put strong constraints on the parameters of dark matter annihilation. In this article, we suggest another robust way to constrain the parameters of dark matter annihilation.…
We propose a novel mechanism for dark matter to explain the observed annual modulation signal at DAMA/LIBRA which avoids existing constraints from every other dark matter direct detection experiment including CRESST, CDMS, and XENON10. The…
We present a new mechanism for thermally produced dark matter, based on a semi-annihilation-like process, $\chi+ \chi +\text{SM} \rightarrow \chi + \text{SM}$, with intriguing consequences for the properties of dark matter. First, its mass…
Detection of a surprisingly high flux of positron annihilation radiation from the inner galaxy has motivated the proposal that dark matter is made of weakly interacting light particles (possibly as light as the electron). This scenario is…
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…
Dark matter semi-annihilation is a process through which two dark matter candidates annihilate to a single dark matter particle and a non-dark matter particle. Such processes are common when the symmetry stabilizing the dark matter differs…
The XENON1T dark matter experiment recently reported 0.65 ton-year exposure measurement on electron recoils , which shows an excess in $2\sim 3$ KeV recoils above the detector background. In this paper we present a Pseudo-Dirac dark matter…
We show that the excess in electron recoil events seen by the XENON1T experiment can be explained by relatively low-mass Luminous Dark Matter candidate. The dark matter scatters inelastically in the detector (or the surrounding rock), to…
We show that primordial (nearly) extremal black holes with a wide range of masses from the Planck scale to around $10^9$ g could be cosmologically stable and explain dark matter, given a dark electromagnetism and a heavy dark electron. For…
We extend the Standard Model by adding two gauge-singlet $\mathbb{Z}_{2}$% -symmetric scalar fields that interact with visible matter only through the Higgs particle. One is a stable dark matter WIMP, and the other one undergoes a…
Semi-annihilation is a generic feature of dark matter theories stabilised by symmetries larger than a $Z_2$. It contributes to thermal freeze out, but is irrelevant for direct and collider searches. This allows semi-annihilating dark matter…