Constraints on α -attractor inflation and reheating

Yoshiki Ueno, Kazuhiro Yamamoto

Research output: Contribution to journalArticle

30 Citations (Scopus)

Abstract

We investigate a constraint on reheating followed by α-attractor-type inflation (the E-model and T-model) from an observation of the spectral index ns. When the energy density of the Universe is dominated by an energy component with the cosmic equation-of-state parameter wre during reheating, its e-folding number Nre and the reheating temperature Tre are bounded depending on wre. When the reheating epoch consists of two phases - where the energy density of the Universe is dominated by uniform inflaton field oscillations in the first phase and by relativistic nonthermalized particles in the second phase - we find a constraint on the e-folding number of the first oscillation phase, Nsc, depending on the parameters of the inflaton potential. For the simplest perturbative reheating scenario, we find the lower bound for a coupling constant of inflaton decay in the E-model and T-model depending on the model parameters. We also find a constraint on the α parameter, α0.01, for the T-model and E-model when we assume a broad resonance reheating scenario.

Original languageEnglish
Article number083524
JournalPhysical Review D
Volume93
Issue number8
DOIs
Publication statusPublished - Apr 28 2016
Externally publishedYes

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heating
folding
flux density
universe
oscillations
relativistic particles
equations of state
time measurement
decay
temperature
energy

All Science Journal Classification (ASJC) codes

  • Physics and Astronomy (miscellaneous)

Cite this

Constraints on α -attractor inflation and reheating. / Ueno, Yoshiki; Yamamoto, Kazuhiro.

In: Physical Review D, Vol. 93, No. 8, 083524, 28.04.2016.

Research output: Contribution to journalArticle

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