Related papers: Inelastic dark matter, small scale problems, and t…
We investigate a recently proposed non-thermal mechanism for dark matter production, in which a small initial dark matter ($\chi$) number density undergoes exponential growth through scatterings with bath particles ($\phi$) in the early…
In this work, we explore the phenomenology of generalized dark matter (GDM) which interacts with photons ($\gamma$). We assume that DM establishes elastic scattering with $\gamma$ when it has already become nonrelativistic, otherwise the…
We present a model for dark matter with extra spatial dimensions in which Standard-Model (SM) fermions have localized wave functions. The underlying gauge group is $G_{\rm SM} \otimes {\rm U}(1)_z$, and the dark matter particle is a…
A model of dark sector where $O({\rm few~GeV})$ mass dark matter particles $\chi$ couple to a lighter dark force mediator $V$, $m_V \ll m_\chi$, is motivated by the recently discovered mismatch between simulated and observed shapes of…
The XENON1T excess of keV electron recoil events may be induced by the scattering of electrons and long-lived particles with MeV mass and high-speed. We consider a tangible model composed of two scalar MeV dark matter (DM) particles $S_A$…
The recently reported excess in XENON1T is explained by new leptonic forces, which are free from gauge anomalies. We focus on two scenarios with and without dark matter. In Scenario #1, the gauge boson of gauged lepton number…
The parameter space of freeze-in dark matter (DM) with mass $m_\chi$ through light dark photon (``minimal freeze-in DM'') is currently being probed by direct detection experiments through electron and nuclear recoil. Exploring the DM…
We consider a recently proposed model in which dark matter interacts with a thermal background of dark radiation. Dark radiation consists of relativistic degrees of freedom which allow larger values of the expansion rate of the universe…
In the scenario with a multiplicity of sectors which independently break supersymmetry, multiplicity of goldstini are predicted. We propose a new interpretation of the electron recoil excess at 2-7 keV observed in the XENON1T experiment…
We study electroweak scale Dark Matter (DM) whose interactions with baryonic matter are mediated by a heavy anomalous $Z'$. We emphasize that when the DM is a Majorana particle, its low-velocity annihilations are dominated by loop…
For dark matter (DM) direct detections, the kinematic effects such as those of the inelastic scattering can play important role in light DM searches. The light DM detection is generally difficult because of its small recoil energy. But the…
In this letter, we report precise and robust observational constraints on dark matter-dark energy scattering cross section, using the latest data from cosmic microwave background (CMB) Planck temperature and polarization, baryon acoustic…
The search for dark matter, the missing mass of the Universe, is one of the most active fields of study within particle physics. The XENON1T experiment recently observed a 3.5$\sigma$ excess potentially consistent with dark matter, or with…
Thermal freeze-out offers an attractive explanation of the dark matter density free from fine-tuning of initial conditions. For dark matter with a mass below tens of MeV, photons, electrons, and neutrinos are the only available direct…
The elastic scattering between dark matter (DM) and radiation can potentially explain small-scale observations that the cold dark matter faces as a challenge, as damping density fluctuations via dark acoustic oscillations in the early…
We take into account a generic form of a Dirac fermionic dark matter (DM), which communicates with the Standard Model quarks via a scalar mediator, in a model-independent way. Four special interaction scenarios are investigated, where one…
All pieces of concrete evidence for phenomena outside the standard model (SM) - neutrino masses and dark matter - are consistent with the existence of new degrees of freedom that interact very weakly, if at all, with those in the SM. We…
We derive new bounds on hadronically-interacting, sub-GeV mass dark matter. First, we show that one-loop interactions with photons can be sufficient to maintain equilibrium between the dark matter and Standard Model sectors at MeV…
The existence of the neutrino mass and flavor mixing have been experimentally verified. These phenomena strongly motivate to extend the Standard Model (SM). Amongst many possibilities, a simple and interesting extension of the SM can be…
We study a $U(1)_{B-L}$ extension of the Standard Model (SM) in which Dirac neutrino masses are generated radiatively at the one-loop level through the exchange of new beyond the SM fields. This framework establishes a direct connection…