Power law $\alpha$-Starobinsky inflation

Abstract

In this work we consider a generalization of Starobinsky inflation obtained by combining power law ($R^{\beta }$), and $\alpha$-Starobinsky inflation ($E$-model). The Einstein frame potential for this model is that of power law Starobinsky inflation modified by a parameter $\alpha$ in the exponential. After computing power spectra for scalar and tensor perturbations numerically, we perform MCMC analysis to put constraints on the potential parameters $\alpha$, $\beta$ and $M$, and the number of e-foldings $N_{pivot}$ during inflation, using Planck-2018, BICEP/Keck (BK18), DES and BAO observations. We find ${\log }_{10}\alpha =0.37_{-0.85}^{+0.82}$, $\beta =1.969_{-0.023}^{+0.020}$, $M=\left(3.54_{-1.73}^{+2.62}\right)\times 10^{-5}$ and $N_{pivot}=47\pm 10$. With these mean values of the potential parameters $\alpha$ and $\beta$, and varying $N_{pivot}$ between $40$ to $55$, we also find that the $r-n_s$ predictions of our model lie well within the $1\sigma$ bounds of joint constraints from combined analysis of ACT, Planck-2018, BICEP and BAO observations. We compute the Bayesian evidences for our proposed model, power law Starobinsky inflation, $\alpha$-Starobinsky inflation and Starobinsky inflation. Considering the Starobinsky model as the base model, we calculate the Bayes factor and find that our proposed model is mildly favored by the CMB and LSS observations.

arXiv commentSubstantially revised, New references added. Referee's comments/suggestions incorporated, Version accepted for publication in Physical Review D. '

References in corpus (48)

• Seven-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Interpretation
• Efficient Computation of CMB anisotropies in closed FRW models
• Unified cosmic history in modified gravity: from F(R) theory to Lorentz non-invariant models
• f(R) theories
• Cosmological parameters from CMB and other data: a Monte-Carlo approach
• Modified Gravity Theories on a Nutshell: Inflation, Bounce and Late-time Evolution
• The Eleventh and Twelfth Data Releases of the Sloan Digital Sky Survey: Final Data from SDSS-III
• Planck 2018 results. X. Constraints on inflation
• BICEP2 I: Detection Of B-mode Polarization at Degree Angular Scales
• Bayes in the sky: Bayesian inference and model selection in cosmology
• Encyclopaedia Inflationaris
• Inflation Dynamics and Reheating
• BICEP / Keck XIII: Improved Constraints on Primordial Gravitational Waves using Planck, WMAP, and BICEP/Keck Observations through the 2018 Observing Season
• Superconformal Inflationary $\alpha$-Attractors
• A more accurate analytic calculation of the spectrum of cosmological perturbations produced during inflation
• Minimal Supergravity Models of Inflation
• Starobinsky-like Inflationary Models as Avatars of No-Scale Supergravity
• GetDist: a Python package for analysing Monte Carlo samples
• No-Scale Supergravity Realization of the Starobinsky Model of Inflation
• Improved limits on the tensor-to-scalar ratio using BICEP and Planck
• Inflation after WMAP3: Confronting the Slow-Roll and Exact Power Spectra with CMB Data
• Planck intermediate results. XXX. The angular power spectrum of polarized dust emission at intermediate and high Galactic latitudes
• Constraints on α-attractor inflation and reheating
• Dark Energy Survey Year 1 Results: Cosmological Constraints from Cluster Abundances, Weak Lensing, and Galaxy Correlations
• Bayesian Analysis of Inflation: Parameter Estimation for Single Field Models
• Consistency relation for $R^p$ inflation
• BICEP/Keck Constraints on Attractor Models of Inflation and Reheating
• Analytic extensions of Starobinsky model of inflation
• Compatibility of Planck and BICEP2 in the Light of Inflation
• Inflationary Attractors in $F(R)$ Gravity
• Keeping the relation between the Starobinsky model and no-scale supergravity ACTive
• Starobinsky-like Inflation, Supercosmology and Neutrino Masses in No-Scale Flipped SU(5)
• Unified No-Scale Attractors
• Inflationary Attractors Predictions for Static Neutron Stars in the Mass-Gap Region
• Marginally Deformed Starobinsky Gravity
• Cosmology with a Master Coupling in Flipped SU(5) $\times$ U(1): The ${\lambda }_6$ Universe
• Starobinsky-Like Inflation and Neutrino Masses in a No-Scale SO(10) Model
• Superstring-Inspired Particle Cosmology: Inflation, Neutrino Masses, Leptogenesis, Dark Matter & the SUSY Scale
• Power law Starobinsky model of inflation from no-scale SUGRA
• Conformal inflation from the Higgs
• From $R^2$ Gravity to No-Scale Supergravity
• Observational constraints on $\alpha$-attractor inflationary models with a Higgs-like potential
• Phenomenology and Cosmology of No-Scale Attractor Models of Inflation
• $\alpha$-attractor from superconformal E-models in brane inflation
• Generalized $R^p$-attractor Cosmology in the Jordan and Einstein Frames: New Type of Attractors and Revisiting Standard Jordan Frame $R^p$ Inflation
• Brane inflation and the robustness of the Starobinsky inflationary model
• Preheating constraints in $\alpha$-attractor inflation and Gravitational Waves production
• Numerical analysis of the generalized Starobinsky inflationary model

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