相关论文: Freeze-in at stronger coupling
We investigate constraints on the new $B-L$ gauge boson ($Z_{BL}$) mass and coupling ($g_{BL}$) in a $U(1)_{B-L}$ extension of the standard model (SM) with an SM singlet Dirac fermion ($\zeta$) as dark matter (DM). The DM particle $\zeta$…
Models with a tiny coupling $\lambda$ between the dark matter and the Standard Model, $\lambda \sim v/M_\text{Pl}\sim 10^{-16}$, can yield the measured relic abundance through the thermal process known as freeze-in. We propose to interpret…
Thermal freeze-out is a compelling framework for naturally generating the dark matter abundance. We systematically study a broad range of dark matter and mediator particle combinations that can viably realize thermal freeze-out, focusing on…
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,…
We present a thorough analysis of the sequential freeze-in mechanism for dark matter production in the early universe. In this mechanism the dark matter relic density results from pair annihilation of mediator particles which are themselves…
Dark matter (DM) could couple to particles in the Standard Model (SM) through a light vector mediator. In the limit of small coupling, this portal could be responsible for producing the observed DM abundance through a mechanism known as…
We propose a new mechanism for thermal dark matter freezeout, termed Co-Decaying Dark Matter. Multi-component dark sectors with degenerate particles and out-of-equilibrium decays can co-decay to obtain the observed relic density. The dark…
We initiate the study of novel thermal dark matter (DM) scenarios where present-day annihilation of DM in the galactic center produces boosted stable particles in the dark sector. These stable particles are typically a subdominant DM…
Non-thermal dark matter generation is an appealing alternative to the standard paradigm of thermal WIMP dark matter. We reconsider non-thermal production mechanisms in a systematic way, and develop a numerical code for accurate computations…
At the tail of its velocity distribution, cold dark matter (DM) can annihilate at finite temperature to states heavier than itself. We explore the possibility that DM freezeout is dictated by these "forbidden annihilations" at the…
It is generically believed that the two-body scattering is suppressed by higher-order weak couplings with respect to the two-body decay. We show that this does not always hold when a heavy particle is produced by forbidden decay in a…
Freeze-out or freeze-in during a period of early matter domination can yield the correct dark matter abundance for small values of the velocity-averaged annihilation cross section, $\langle \sigma_{\rm ann} v \rangle_{\rm f} < 3 \times…
We explore a new mechanism for reproducing the Dark Matter (DM) abundance: scatterings of one DM particle on light Standard Model particles. Strong bounds on its decays can be satisfied if DM undergoes freeze-in and has a mass around or…
Self-Interacting Dark Matter models can successfully explain dark matter (DM) production through interactions confined within the dark sector. However, they often lack measurable experimental signals due to their secluded nature. Including…
There are many extensions of the Standard Model with a dark matter (DM) candidate obtained via the freeze-out mechanism. It can happen that after all experimental and theoretical constraints are taken into account, all parameter points have…
We study the impact of thermalization and number-changing processes in the dark sector on the yield of gravitationally produced dark matter (DM). We take into account the DM production through the $s$-channel exchange of a massless graviton…
We examine and point out the importance of a regime of dark matter production through the freeze-in mechanism that results from a large thermal correction to a decaying mediator particle mass from hot plasma in the early Universe. We show…
We investigate the out-of-equilibrium production of scalar dark matter (DM) from the inflaton condensate during inflation and reheating. We assume that this scalar couples only to the inflaton via a direct quartic coupling and is minimally…
The connection between a hidden nonthermal sector and a thermal plasma can be established by a light thermal fermion mediator. When the fermion mediator is much lighter than the hidden species, kinematically forbidden decay of the mediator…
New gauge bosons at the MeV scale with tiny gauge couplings (so-called dark photons) can be responsible for the freeze-in production of dark matter and provide a clear target for present and future experiments. We study the effects of…