Probing gravitational dark matter
Abstract
So far all evidences of dark matter (DM) come from astrophysical and cosmological observations, due to the gravitational interactions of DM. It is possible that the true DM particle in the universe joins gravitational interactions only, but nothing else. Such a Gravitational DM (GDM) may act as a weakly interacting massive particle (WIMP), which is conceptually simple and attractive. In this work, we explore this direction by constructing the simplest scalar GDM particle χ{sub s}. It is a Z{sub 2} odd singlet under the standard model (SM) gauge group, and naturally joins the unique dimension4 interaction with Ricci curvature, ξ{sub s}χ{sub s}{sup 2}R, where ξ{sub s} is the dimensionless nonminimal coupling. We demonstrate that this gravitational interaction ξ{sub s}χ{sub s}{sup 2}R, together with Higgscurvature nonminimal coupling term ξ{sub h}H{sup †}HR, induces effective couplings between χ{sub s}{sup 2} and SM fields, and can account for the observed DM thermal relic abundance. We analyze the annihilation cross sections of GDM particles and derive the viable parameter space for realizing the DM thermal relic density. We further study the direct/indirect detections and the collider signatures of such a scalar GDM. These turn out to be highly predictive and testable.
 Authors:
 Institute of Modern Physics and Center for High Energy Physics, Tsinghua University, Beijing 100084 (China)
 Publication Date:
 OSTI Identifier:
 22525923
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2015; Journal Issue: 03; Other Information: Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ANNIHILATION; ASTROPHYSICS; CROSS SECTIONS; DENSITY; GRAVITATIONAL INTERACTIONS; HIGGS BOSONS; HIGGS MODEL; NONLUMINOUS MATTER; PROBES; SCALARS; SPACE; STANDARD MODEL; UNIVERSE; WIMPS
Citation Formats
Ren, Jing, and He, HongJian, Email: jingren2004@gmail.com, Email: hjhe@tsinghua.edu.cn. Probing gravitational dark matter. United States: N. p., 2015.
Web. doi:10.1088/14757516/2015/03/052.
Ren, Jing, & He, HongJian, Email: jingren2004@gmail.com, Email: hjhe@tsinghua.edu.cn. Probing gravitational dark matter. United States. doi:10.1088/14757516/2015/03/052.
Ren, Jing, and He, HongJian, Email: jingren2004@gmail.com, Email: hjhe@tsinghua.edu.cn. 2015.
"Probing gravitational dark matter". United States.
doi:10.1088/14757516/2015/03/052.
@article{osti_22525923,
title = {Probing gravitational dark matter},
author = {Ren, Jing and He, HongJian, Email: jingren2004@gmail.com, Email: hjhe@tsinghua.edu.cn},
abstractNote = {So far all evidences of dark matter (DM) come from astrophysical and cosmological observations, due to the gravitational interactions of DM. It is possible that the true DM particle in the universe joins gravitational interactions only, but nothing else. Such a Gravitational DM (GDM) may act as a weakly interacting massive particle (WIMP), which is conceptually simple and attractive. In this work, we explore this direction by constructing the simplest scalar GDM particle χ{sub s}. It is a Z{sub 2} odd singlet under the standard model (SM) gauge group, and naturally joins the unique dimension4 interaction with Ricci curvature, ξ{sub s}χ{sub s}{sup 2}R, where ξ{sub s} is the dimensionless nonminimal coupling. We demonstrate that this gravitational interaction ξ{sub s}χ{sub s}{sup 2}R, together with Higgscurvature nonminimal coupling term ξ{sub h}H{sup †}HR, induces effective couplings between χ{sub s}{sup 2} and SM fields, and can account for the observed DM thermal relic abundance. We analyze the annihilation cross sections of GDM particles and derive the viable parameter space for realizing the DM thermal relic density. We further study the direct/indirect detections and the collider signatures of such a scalar GDM. These turn out to be highly predictive and testable.},
doi = {10.1088/14757516/2015/03/052},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 03,
volume = 2015,
place = {United States},
year = 2015,
month = 3
}

So far all evidences of dark matter (DM) come from astrophysical and cosmological observations, due to the gravitational interactions of DM. It is possible that the true DM particle in the universe joins gravitational interactions only, but nothing else. Such a Gravitational DM (GDM) may act as a weakly interacting massive particle (WIMP), which is conceptually simple and attractive. In this work, we explore this direction by constructing the simplest scalar GDM particle χ{sub s}. It is a ℤ{sub 2} odd singlet under the standard model (SM) gauge group, and naturally joins the unique dimension4 interaction with Ricci curvature, ξ{submore »

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