TY - JOUR

T1 - Inflection-point inflation and dark matter redux

AU - Ghoshal, Anish

AU - Lambiase, Gaetano

AU - Pal, Supratik

AU - Paul, Arnab

AU - Porey, Shiladitya

N1 - Acknowledgments: Authors acknowledge communications with Alexander Dmitrievich Dolgov, Anupam Mazumdar, Arindam Chatterjee, Yong Xu and Raghavan Rangarajan. Work of Shiladitya Porey is funded by RSF Grant 19-42-02004. Supratik Pal thanks Department of Science and Technology, Govt. of India for partial support through Grant No. NMICPS/006/MD/2020-21. Publisher Copyright: © 2022, The Author(s).

PY - 2022/9

Y1 - 2022/9

N2 - We investigate for viable models of inflation that can successfully produce dark matter (DM) from inflaton decay process, satisfying all the constraints from Cosmic Microwave Background (CMB) and from some other observations. In particular, we analyze near-inflection-point small field inflationary scenario with non-thermal production of fermionic DM from the decaying inflaton field during the reheating era. To this end, we propose two different models of inflation with polynomial potential. The potential of Model I contains terms proportional to linear, quadratic, and quartic in inflaton; whereas in Model II, the potential contains only even power of inflaton and the highest term is sextic in inflaton. For both the models, we find out possible constraints on the model parameters which lead to proper inflationary parameters from CMB data with a very small tensor-to-scalar ratio, as expected from a small-field model. With the allowed parameter space from CMB, we then search for satisfactory relic abundance for DM, that can be produced from inflaton via reheating, to match with the present-day cold dark matter (CDM) relic density for the parameter spaces of the DM χ mass and Yukawa couplings in the range 10−9 ≳ yχ ≳ 10−15 and 103GeV ≲ mχ ≲ 109GeV. The DM relic is associated with the inflection-points in each model via maximum temperature reached in the early universe during its production. Finally, we find out allowed parameter space coming out of combined constraints from stability analysis for both SM Higgs and DM decays from inflaton as well as from BBN and Lyman-α bounds.

AB - We investigate for viable models of inflation that can successfully produce dark matter (DM) from inflaton decay process, satisfying all the constraints from Cosmic Microwave Background (CMB) and from some other observations. In particular, we analyze near-inflection-point small field inflationary scenario with non-thermal production of fermionic DM from the decaying inflaton field during the reheating era. To this end, we propose two different models of inflation with polynomial potential. The potential of Model I contains terms proportional to linear, quadratic, and quartic in inflaton; whereas in Model II, the potential contains only even power of inflaton and the highest term is sextic in inflaton. For both the models, we find out possible constraints on the model parameters which lead to proper inflationary parameters from CMB data with a very small tensor-to-scalar ratio, as expected from a small-field model. With the allowed parameter space from CMB, we then search for satisfactory relic abundance for DM, that can be produced from inflaton via reheating, to match with the present-day cold dark matter (CDM) relic density for the parameter spaces of the DM χ mass and Yukawa couplings in the range 10−9 ≳ yχ ≳ 10−15 and 103GeV ≲ mχ ≲ 109GeV. The DM relic is associated with the inflection-points in each model via maximum temperature reached in the early universe during its production. Finally, we find out allowed parameter space coming out of combined constraints from stability analysis for both SM Higgs and DM decays from inflaton as well as from BBN and Lyman-α bounds.

KW - Early Universe Particle Physics

KW - Particle Nature of Dark Matter

UR - http://www.scopus.com/inward/record.url?scp=85139184416&partnerID=8YFLogxK

U2 - 10.1007/JHEP09(2022)231

DO - 10.1007/JHEP09(2022)231

M3 - Article

AN - SCOPUS:85139184416

VL - 2022

JO - Journal of High Energy Physics

JF - Journal of High Energy Physics

SN - 1029-8479

IS - 9

M1 - 231

ER -