A Global Overview of Starobinsky Inflation beyond slow-roll with CMB-BAO data
Abstract
We perform a global analysis of the Starobinsky inflation using most recent CMB data from ACT and SPT together with DESI BAO measurements. By directly solving the equations of motion, we find relatively stronger constraints on the model parameters than those obtained under the slow-roll approximation from the baseline ΛCDM parameters As and ns. We translate these constraints into limits on the reheating temperature. We also discuss the dependence of the prior choices of the model parameters. Further, the correlation of the model parameters with the BAO parameter rd h is also studied. We further investigate the impact of the global analysis on the dimension-six R3 modified Starobinsky model, deriving constraints on its additional parameters. Finally, we also provide parameter limits on the effective inflationary Hubble slow-roll (HSR) and potential slow-roll (PSR) parametrization.
Related
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BibTeX
@misc{tarun2026global,
title = {{A Global Overview of Starobinsky Inflation beyond slow-roll with CMB-BAO data}},
author = {Tarun and Tanmoy Modak and Björn Malte Schäfer},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.19296},
eprint = {2609.19296},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.19296},
}
RIS
TY - UNPB
TI - A Global Overview of Starobinsky Inflation beyond slow-roll with CMB-BAO data
AU - Tarun
AU - Tanmoy Modak
AU - Björn Malte Schäfer
PY - 2026
DA - 2026/09/16
PB - arXiv
DO - 10.48550/arxiv.2609.19296
UR - https://arxiv.org/abs/2609.19296
AB - We perform a global analysis of the Starobinsky inflation using most recent CMB data from ACT and SPT together with DESI BAO measurements. By directly solving the equations of motion, we find relatively stronger constraints on the model parameters than those obtained under the slow-roll approximation from the baseline ΛCDM parameters A_s and n_s. We translate these constraints into limits on the reheating temperature. We also discuss the dependence of the prior choices of the model parameters. Further, the correlation of the model parameters with the BAO parameter r_d h is also studied. We further investigate the impact of the global analysis on the dimension-six R^3 modified Starobinsky model, deriving constraints on its additional parameters. Finally, we also provide parameter limits on the effective inflationary Hubble slow-roll (HSR) and potential slow-roll (PSR) parametrization.
ER -