相关论文: When Freeze-out occurs due to a non-Boltzmann supp…
We consider the possibility that thermalized dark-matter particles acquire their mass thanks to the spontaneous breaking of a symmetry below some critical temperature. We describe the regime where a freeze out mechanism takes place shortly…
In some models of thermal relic dark matter, the relic abundance may be set by inelastic scattering processes (rather than annihilations) becoming inefficient as the universe cools down. This effect has been called coscattering. We present…
In the standard thermal relic scenario, dark matter remains in chemical equilibrium with the Standard Model radiation bath until freeze-out occurs at $T \sim m_X/20$, where $m_X$ is the dark matter mass. In this familiar class of models,…
If the interaction rates between the visible and the dark sectors were never strong enough, the observed dark matter relic abundance could have been produced in the early Universe by non-thermal processes. This is what occurs in the…
Chemical equilibrium is a commonly made assumption in the freeze-out calculation of coannihilating dark matter. We explore the possible failure of this assumption and find a new conversion-driven freeze-out mechanism. Considering a…
A novel particle has been and still is an intriguing option to explain the strong evidence for dark matter in our universe. To quantitatively predict the dark matter energy density, two main ingredients are needed: interaction rates and an…
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…
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…
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…
We extend the study of the effect of density perturbations to the well known thermal dark matter freeze-out scenario. We find $\sim 10 \, \%$ enhancements in the cross section are required to match onto the observed relic abundance for…
Traditional computations of the dark matter (DM) relic abundance, for models where attractive self-interactions are mediated by light force-carriers and bound states exist, rely on the solution of a coupled system of classical on-shell…
We consider the decay of a massive particle under the complete or partial domination of the kinetic energy density generated by a quintessential exponential model and we impose a number of observational constraints originating from…
The gamma-ray excess observed from the Galactic Center can be interpreted as dark matter particles annihilating into Standard Model fermions with a cross section near that expected for a thermal relic. Although many particle physics models…
We explore the parameter space of a U(1) extension of the standard model -- also called the super-weak model -- from the point of view of explaining the observed dark matter energy density in the Universe. The new particle spectrum contains…
Dark matter freeze-in at stronger coupling is operative when the Standard Model (SM) bath temperature never exceeds the dark matter mass. An attractive feature of this scenario is that it can be probed by direct detection experiments as…
We investigate a simplified freeze-in dark-matter model in which the dark matter only interacts with the standard-model neutrinos via a light scalar. The extremely small coupling for the freeze-in mechanism is naturally realized in several…
We explore the possibility that dark matter is a pair of vector-like fermionic $\mathrm{SU}(2)_{\rm L}$ doublets and propose a novel mechanism of dark matter production that proceeds through the confinement of the weak sector of the…
In this work we consider a simple model for dark matter and identify regions of parameter space where the relic abundance is set via kinematic thresholds, which open and close due to thermal effects. We discuss instantaneous freeze-out,…
The thermal and expansion history of the Universe before big bang nucleosynthesis is unknown. We investigate the evolution of cosmological perturbations through the transition from an early matter era to radiation domination. We treat…
The existence of a light mediator is beneficial to some phenomena in astroparticle physics, such as the core-cusp problem and diversity problem. It can decouple from Standard Model to avoid direct detection constraints, generally realized…