Clustering properties of a sterile neutrino dark matter candidate
| dc.creator | Boyanovsky, D. | |
| dc.date | 2008-07-03 | |
| dc.date | 2008-12-06 | |
| dc.date.accessioned | 2026-07-07T12:14:54Z | |
| dc.date.available | 2026-07-07T12:14:54Z | |
| dc.description | The clustering properties of sterile neutrinos are studied within an extension of the minimal standard model, where these are produced via the decay of a gauge singlet scalar. The distribution function after decoupling is strongly out of equilibrium. (DM) abundance and phase space density constraints from (dSphs) constrain the mass in the $\mathrm{keV}$ range consistent with a gauge singlet with mass and vacuum expectation value $\sim 100,\mathrm{GeV}$ decoupling at this temperature. The (DM) transfer function and power spectrum are obtained from the solution of the non-relativistic Boltzmann-Vlasov equation in the matter dominated era. The small momentum enhancement of the distribution function leads to long range memory of gravitational clustering and a \emph{substantial enhancement of the power spectrum at small scales compared to a thermal relic or sterile neutrino produced via non-resonant mixing with active neutrinos}. The scale of suppression of the power spectrum for such sterile neutrino with $m\sim \mathrm{keV}$ is $λ\sim 488 ,\mathrm{kpc}$. At large scales $T(k)\sim 1-C, k^2/k^2_{fs}(t_{eq}) +...$ with $C \sim \mathrm{O}(1)$. At small scales $65 \mathrm{kpc} \lesssim λ\lesssim 500 \mathrm{kpc}$ corrections to the fluid description and memory of gravitational clustering become important, and we find $T(k) \simeq 1.902 e^{-k/k_{fs}(t_{eq})}$, where $k_{fs}(t_{eq}) \sim 0.013/\mathrm{kpc}$ is the free streaming wavevector at matter-radiation equality. The enhancement of power at small scales may provide a possible relief to the tension between the constraints from X-ray and Lyman-$α$ forest data. | |
| dc.description | matches version to appear in PRD | |
| dc.identifier | https://arxiv.org/abs/0807.0646 | |
| dc.identifier | http://arxiv.org/abs/0807.0646 | |
| dc.identifier | Phys.Rev.D78:103505,2008 | |
| dc.identifier | doi:10.1103/PhysRevD.78.103505 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/211351 | |
| dc.subject | Astrophysics | |
| dc.subject | High Energy Physics - Phenomenology | |
| dc.title | Clustering properties of a sterile neutrino dark matter candidate | |
| dc.type | text |