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Related papers: Light Dark Matter from Entropy Dilution

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An internally thermalized dark matter (DM) with only gravitational interaction with the standard model (SM) particles at low temperatures, may undergo number-changing self-scatterings in the early Universe, eventually freezing out to the…

High Energy Physics - Phenomenology · Physics 2022-11-17 Avirup Ghosh , Sourav Gope , Satyanarayan Mukhopadhyay

We demonstrate that if the dark matter (DM) in the Universe contains multiple components,the interactions between the DM components may induce DM conversions. It is then possible that the lightest DM component with an annihilation cross…

High Energy Physics - Phenomenology · Physics 2011-10-11 Ze-Peng Liu , Yue-Liang Wu , Yu-Feng Zhou

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…

The Lightest Supersymmetric Particle (LSP) makes a good Dark Matter (DM) candidate, since its relic density quite naturally comes out close to the cosmologically required value. This is true even in minimal Supergravity models with…

High Energy Physics - Phenomenology · Physics 2009-09-25 M. Drees

Dark matter (DM) could be a relic of freeze-in through a light mediator, where the DM is produced by extremely feeble, IR-dominated processes in the thermal Standard Model plasma. In the simplest viable models with the DM mass below the MeV…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-15 Cora Dvorkin , Tongyan Lin , Katelin Schutz

The early universe could feature multiple reheating events, leading to jumps in the visible sector entropy density that dilute both particle asymmetries and the number density of frozen-out states. In fact, late time entropy jumps are…

High Energy Physics - Phenomenology · Physics 2017-03-08 Joseph Bramante , James Unwin

We propose a simple mechanism of light dark matter (DM) production from the decay of the oscillating inflaton condensation. If the reheating temperature after inflation is higher than the inflaton mass, which is of the same order of the…

High Energy Physics - Phenomenology · Physics 2021-04-21 Takeo Moroi , Wen Yin

We consider a class of models in which thermal dark matter is lighter than an MeV. If dark matter thermalizes with the Standard Model below the temperature of neutrino-photon decoupling, equilibration and freeze-out cools and heats the…

High Energy Physics - Phenomenology · Physics 2018-03-05 Asher Berlin , Nikita Blinov

Although Planck data supports the standard \Lambda CDM model, it still allows for the presence of Dark Radiation corresponding up to about half an extra standard neutrino species. We propose a scenario for obtaining a fractional "effective…

High Energy Physics - Phenomenology · Physics 2015-06-15 Pasquale Di Bari , Stephen F. King , Alexander Merle

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…

High Energy Physics - Phenomenology · Physics 2022-01-05 Bin Zhu , Murat Abdughani

The particle-physics nature of dark matter (DM) remains one of the central open questions in modern physics. A widely used framework to investigate DM properties is provided by simplified models (DMSimps), which extend the Standard Model…

High Energy Physics - Phenomenology · Physics 2025-10-13 Mattia Di Mauro , Bohan Xie

We present a new study on the Gravity-Mediated Dark Matter (GMDM) scenario, where interactions between dark matter (DM) and the Standard Model are mediated by spin-two particles. Expanding on this established framework, we explore a novel…

High Energy Physics - Phenomenology · Physics 2024-12-12 Hyun Min Lee , Myeonghun Park , Veronica Sanz

We consider a model of dark matter where the mediator corresponds to a superposition of a scalar and pseudoscalar, and the scenario where, after reheating, the number densities of the dark sector particles, i.e. the dark matter and the…

High Energy Physics - Phenomenology · Physics 2025-11-19 Geneviève Bélanger , Aoife Bharucha , Sreemanti Chakraborti , Rashidul Islam , Sophie Mutzel

We present a model where sterile neutrinos with rest masses in the range ~ keV to ~ MeV can be the dark matter and be consistent with all laboratory, cosmological, large-scale structure, as well as x-ray constraints. These sterile neutrinos…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-13 Amol V. Patwardhan , George M. Fuller , Chad T. Kishimoto , Alexander Kusenko

We study the possible signals at LHC of the minimal models of decaying dark matter. Those models are characterized by the fact that DM interacts with SM particles through renormalizable coupling with an additional heavier charged state.…

High Energy Physics - Phenomenology · Physics 2015-06-22 Giorgio Arcadi , Laura Covi , Federico Dradi

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…

High Energy Physics - Phenomenology · Physics 2019-05-29 Asher Berlin , Nikita Blinov

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…

High Energy Physics - Phenomenology · Physics 2019-06-19 Cora Dvorkin , Tongyan Lin , Katelin Schutz

Any form of dark matter which was in thermal equilibrium with the Standard Model in the early Universe must have some annihilation mechanism in order to avoid overclosure. In general, such models are now constrained by the negative…

High Energy Physics - Phenomenology · Physics 2017-05-12 Matthew R. Buckley , David Feld

Dark matter (DM) could be a nonthermal relic that freezes in from extremely weak, sub-Hubble annihilation and decay of Standard Model (SM) particles. The case of Dirac DM freezing in via a dark photon mediator is a well-studied benchmark…

High Energy Physics - Phenomenology · Physics 2023-04-14 Saniya Heeba , Tongyan Lin , Katelin Schutz

The scotogenic model provides a minimal and elegant framework that simultaneously explains neutrino masses and accommodates a viable dark matter (DM) candidate. In this work, we investigate the phenomenology of fermionic DM in the…

High Energy Physics - Phenomenology · Physics 2026-03-09 Abhishek Roy , Rameswar Sahu