Production of gravitational waves during preheating in the Starobinsky inflationary model

• Published in: The European physical journal. C, Particles and fields Vol. 80; no. 6; pp. 1 - 8
• Main Authors: Jin, Guoqiang, Fu, Chengjie, Wu, Puxun, Yu, Hongwei
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.06.2020; Springer; Springer Nature B.V; SpringerOpen
• Subjects: Analysis; Astronomy; Astrophysics and Cosmology; Computer simulation; Elementary Particles; Gravitational waves; Hadrons; Heating; Heavy Ions; Inflation (Finance); Measurement Science and Instrumentation; Nuclear Energy; Nuclear Physics; Physics; Physics and Astronomy; Quantum Field Theories; Quantum Field Theory; Regular Article - Theoretical Physics; Scalars; String Theory
• ISSN: 1434-6044; 1434-6052
• DOI: 10.1140/epjc/s10052-020-8061-0

The production of GWs during preheating in the Starobinsky model with a nonminimally coupled auxiliary scalar field is studied through the lattice simulation in this paper. We find that the GW spectrum Ω gw grows fast with the increase of the absolute value of coupling parameter ξ . This is because the resonant bands become broad with the increase of | ξ | . When ξ < 0 , Ω gw begins to grow once the inflation ends and grows faster than the case of ξ > 0 . Ω gw reaches the maximum at ξ = - 20 ( ξ = 42 for the case ξ > 0 ) and then decreases with slight oscillation. Furthermore we find that the GWs produced in the era of preheating satisfy the limits from the Planck and next-generation CMB experiments.