Matter power spectrum in hidden neutrino interacting dark matter models: a closer look at the collision term
Abstract
Dark Matter (DM) models providing possible alternative solutions to the smallscale crisis of the standard cosmology are nowadays of growing interest. We consider DM interacting with light hidden fermions via wellmotivated fundamental operators showing the resultant matter power spectrum is suppressed on subgalactic scales within a plausible parameter region. Our basic description of the evolution of cosmological perturbations relies on a fully consistent first principles derivation of a perturbed FokkerPlanck type equation, generalizing existing literature. The cosmological perturbation of the FokkerPlanck equation is presented for the first time in two different gauges, where the results transform into each other according to the rules of gauge transformation. Furthermore, our focus lies on a derivation of a broadly applicable and easily computable collision term showing important phenomenological differences to other existing approximations. As one of the main results and concerning the smallscale crisis, we show the equal importance of vector and scalar boson mediated interactions between the DM and the light fermions.
 Authors:
 Institute for Theoretical Physics, GeorgAugust University Göttingen,FriedrichHundPlatz 1, Göttingen, D37077 (Germany)
 Department of Physics and Astronomy, University of California,Riverside, California 92521 (United States)
 Kavli Institute for the Physics and Mathematics of the Universe (WPI),University of Tokyo Institutes for Advanced Study, University of Tokyo,Kashiwa 2778583 (Japan)
 (United States)
 Department of Physics, Saga University,Saga 8408502 (Japan)
 (Japan)
 Publication Date:
 Sponsoring Org.:
 SCOAP3, CERN, Geneva (Switzerland)
 OSTI Identifier:
 22572188
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2016; Journal Issue: 11; Other Information: PUBLISHERID: JCAP11(2016)043; OAI: oai:repo.scoap3.org:17993; ccby Article funded by SCOAP3. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 License. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; COSMOLOGICAL MODELS; COSMOLOGY; DISTURBANCES; FOKKERPLANCK EQUATION; GAUGE INVARIANCE; MATHEMATICAL EVOLUTION; MATHEMATICAL OPERATORS; MATHEMATICAL SOLUTIONS; NONLUMINOUS MATTER; PARTICLE INTERACTIONS; PERTURBATION THEORY
Citation Formats
Binder, Tobias, Covi, Laura, Kamada, Ayuki, Murayama, Hitoshi, Department of Physics, University of California, Berkeley,Berkeley, California 94720, Theoretical Physics Group, Lawrence Berkeley National Laboratory,Berkeley, California 94720, Takahashi, Tomo, Yoshida, Naoki, Department of Physics, University of Tokyo,Tokyo 1130033, and CREST, Japan Science and Technology Agency,418 Honcho, Kawaguchi, Saitama, 3320012. Matter power spectrum in hidden neutrino interacting dark matter models: a closer look at the collision term. United States: N. p., 2016.
Web. doi:10.1088/14757516/2016/11/043.
Binder, Tobias, Covi, Laura, Kamada, Ayuki, Murayama, Hitoshi, Department of Physics, University of California, Berkeley,Berkeley, California 94720, Theoretical Physics Group, Lawrence Berkeley National Laboratory,Berkeley, California 94720, Takahashi, Tomo, Yoshida, Naoki, Department of Physics, University of Tokyo,Tokyo 1130033, & CREST, Japan Science and Technology Agency,418 Honcho, Kawaguchi, Saitama, 3320012. Matter power spectrum in hidden neutrino interacting dark matter models: a closer look at the collision term. United States. doi:10.1088/14757516/2016/11/043.
Binder, Tobias, Covi, Laura, Kamada, Ayuki, Murayama, Hitoshi, Department of Physics, University of California, Berkeley,Berkeley, California 94720, Theoretical Physics Group, Lawrence Berkeley National Laboratory,Berkeley, California 94720, Takahashi, Tomo, Yoshida, Naoki, Department of Physics, University of Tokyo,Tokyo 1130033, and CREST, Japan Science and Technology Agency,418 Honcho, Kawaguchi, Saitama, 3320012. 2016.
"Matter power spectrum in hidden neutrino interacting dark matter models: a closer look at the collision term". United States.
doi:10.1088/14757516/2016/11/043.
@article{osti_22572188,
title = {Matter power spectrum in hidden neutrino interacting dark matter models: a closer look at the collision term},
author = {Binder, Tobias and Covi, Laura and Kamada, Ayuki and Murayama, Hitoshi and Department of Physics, University of California, Berkeley,Berkeley, California 94720 and Theoretical Physics Group, Lawrence Berkeley National Laboratory,Berkeley, California 94720 and Takahashi, Tomo and Yoshida, Naoki and Department of Physics, University of Tokyo,Tokyo 1130033 and CREST, Japan Science and Technology Agency,418 Honcho, Kawaguchi, Saitama, 3320012},
abstractNote = {Dark Matter (DM) models providing possible alternative solutions to the smallscale crisis of the standard cosmology are nowadays of growing interest. We consider DM interacting with light hidden fermions via wellmotivated fundamental operators showing the resultant matter power spectrum is suppressed on subgalactic scales within a plausible parameter region. Our basic description of the evolution of cosmological perturbations relies on a fully consistent first principles derivation of a perturbed FokkerPlanck type equation, generalizing existing literature. The cosmological perturbation of the FokkerPlanck equation is presented for the first time in two different gauges, where the results transform into each other according to the rules of gauge transformation. Furthermore, our focus lies on a derivation of a broadly applicable and easily computable collision term showing important phenomenological differences to other existing approximations. As one of the main results and concerning the smallscale crisis, we show the equal importance of vector and scalar boson mediated interactions between the DM and the light fermions.},
doi = {10.1088/14757516/2016/11/043},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 11,
volume = 2016,
place = {United States},
year = 2016,
month =
}

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