- http://iopscience.iop.org/article/10.1088/1475-7516/2016/08/035/meta
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Research output: Contribution to Journal/Magazine › Journal article › peer-review

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In: Journal of Cosmology and Astroparticle Physics, Vol. 2016, No. 8, 035, 17.08.2016.

Research output: Contribution to Journal/Magazine › Journal article › peer-review

McDonald, J 2016, 'Warm dark matter via ultra-violet freeze-in: reheating temperature and non-thermal distribution for fermionic Higgs portal dark matter ', *Journal of Cosmology and Astroparticle Physics*, vol. 2016, no. 8, 035. https://doi.org/10.1088/1475-7516/2016/08/035

McDonald, J. (2016). Warm dark matter via ultra-violet freeze-in: reheating temperature and non-thermal distribution for fermionic Higgs portal dark matter . *Journal of Cosmology and Astroparticle Physics*, *2016*(8), Article 035. https://doi.org/10.1088/1475-7516/2016/08/035

McDonald J. Warm dark matter via ultra-violet freeze-in: reheating temperature and non-thermal distribution for fermionic Higgs portal dark matter . Journal of Cosmology and Astroparticle Physics. 2016 Aug 17;2016(8):035. doi: 10.1088/1475-7516/2016/08/035

@article{0243accd7ea54cf18d475745b399539a,

title = "Warm dark matter via ultra-violet freeze-in: reheating temperature and non-thermal distribution for fermionic Higgs portal dark matter ",

abstract = "Warm dark matter (WDM) of order keV mass may be able to resolve the disagreement between structure formation in cold dark matter simulations and observations. The detailed properties of WDM will depend upon its energy distribution, in particular how it deviates from the thermal distribution usually assumed in WDM simulations. Here we focus on WDM production via the Ultra-Violet (UV) freeze-in mechanism, for the case of fermionic Higgs portal dark matter ψ produced via the portal interaction ψH†H/Λ. We introduce a new method to simplify the computation of the non-thermal energy distribution of dark matter from freeze-in. We show that the non-thermal energy distribution from UV freeze-in is hotter than the corresponding thermal distribution and has the form of a Bose-Einstein distribution with a non-thermal normalization. The resulting range of dark matter fermion mass consistent with observations is 5-7 keV. The reheating temperature must satisfy TR 120 GeV in order to account for the observed dark matter density when mψ keV, where the lower bound on TR corresponds to the limit where the fermion mass is entirely due to electroweak symmetry breaking via the portal interaction. The corresponding bound on the interaction scale is Λ 6.0 × 109 GeV.",

keywords = "dark matter theory, physics of the early universe",

author = "John McDonald",

year = "2016",

month = aug,

day = "17",

doi = "10.1088/1475-7516/2016/08/035",

language = "English",

volume = "2016",

journal = "Journal of Cosmology and Astroparticle Physics",

issn = "1475-7516",

publisher = "IOP Publishing",

number = "8",

}

TY - JOUR

T1 - Warm dark matter via ultra-violet freeze-in

T2 - reheating temperature and non-thermal distribution for fermionic Higgs portal dark matter

AU - McDonald, John

PY - 2016/8/17

Y1 - 2016/8/17

N2 - Warm dark matter (WDM) of order keV mass may be able to resolve the disagreement between structure formation in cold dark matter simulations and observations. The detailed properties of WDM will depend upon its energy distribution, in particular how it deviates from the thermal distribution usually assumed in WDM simulations. Here we focus on WDM production via the Ultra-Violet (UV) freeze-in mechanism, for the case of fermionic Higgs portal dark matter ψ produced via the portal interaction ψH†H/Λ. We introduce a new method to simplify the computation of the non-thermal energy distribution of dark matter from freeze-in. We show that the non-thermal energy distribution from UV freeze-in is hotter than the corresponding thermal distribution and has the form of a Bose-Einstein distribution with a non-thermal normalization. The resulting range of dark matter fermion mass consistent with observations is 5-7 keV. The reheating temperature must satisfy TR 120 GeV in order to account for the observed dark matter density when mψ keV, where the lower bound on TR corresponds to the limit where the fermion mass is entirely due to electroweak symmetry breaking via the portal interaction. The corresponding bound on the interaction scale is Λ 6.0 × 109 GeV.

AB - Warm dark matter (WDM) of order keV mass may be able to resolve the disagreement between structure formation in cold dark matter simulations and observations. The detailed properties of WDM will depend upon its energy distribution, in particular how it deviates from the thermal distribution usually assumed in WDM simulations. Here we focus on WDM production via the Ultra-Violet (UV) freeze-in mechanism, for the case of fermionic Higgs portal dark matter ψ produced via the portal interaction ψH†H/Λ. We introduce a new method to simplify the computation of the non-thermal energy distribution of dark matter from freeze-in. We show that the non-thermal energy distribution from UV freeze-in is hotter than the corresponding thermal distribution and has the form of a Bose-Einstein distribution with a non-thermal normalization. The resulting range of dark matter fermion mass consistent with observations is 5-7 keV. The reheating temperature must satisfy TR 120 GeV in order to account for the observed dark matter density when mψ keV, where the lower bound on TR corresponds to the limit where the fermion mass is entirely due to electroweak symmetry breaking via the portal interaction. The corresponding bound on the interaction scale is Λ 6.0 × 109 GeV.

KW - dark matter theory

KW - physics of the early universe

U2 - 10.1088/1475-7516/2016/08/035

DO - 10.1088/1475-7516/2016/08/035

M3 - Journal article

VL - 2016

JO - Journal of Cosmology and Astroparticle Physics

JF - Journal of Cosmology and Astroparticle Physics

SN - 1475-7516

IS - 8

M1 - 035

ER -