Shapes of non-Gaussianity in warm inflation

Abstract

Sphaleron heating has been recently proposed as a mechanism to realize warm inflation when inflaton is an axion coupled to pure Yang-Mills. As a result of heating, there is a friction coefficient $\gamma \propto T^3$ in the equation of motion for the inflaton, and a thermal contribution to cosmological fluctuations. Without the knowledge of the inflaton potential, non-Gaussianity is the most promising way of searching for the signatures of this model. Building on an earlier work by Bastero-Gil, Berera, Moss and Ramos, we compute the scalar three-point correlation function and point out some distinct features in the squeezed and folded limits. As a detection strategy, we show that the combination of the equilateral template and one new template has a large overlap with the shape of non-Gaussianity over the range $0.01\le \gamma /H\le 1000$, and in this range $0.7<|f_{\mathrm{NL}}|<50$.

v2: JCAP version, 35 pages, 9 figures, extra refs and comments with respect to v1

References in corpus (10)

• The Sphaleron Rate in SU(N) Gauge Theory
• Trapped Inflation
• Chiral Anomaly, Schwinger Effect, Euler-Heisenberg Lagrangian, and application to axion inflation
• Theory of non-Gaussianity in warm inflation
• Gravitational Waves and the Scale of Inflation
• Thermalized Axion Inflation
• Gravitational wave background from non-Abelian reheating after axion-like inflation
• Warming up cold inflation
• Higher N-point function data analysis techniques for heavy particle production and WMAP results
• The spectrum of tensor perturbations in warm inflation

Cited by in corpus (20)

• Recent developments in warm inflation
• The warm inflation story
• The Open Effective Field Theory of Inflation
• Gravitational wave background from vacuum and thermal fluctuations during axion-like inflation
• Warm Inflation with the Standard Model
• Viability of warm inflation with standard model interactions
• WI2easy: warm inflation dynamics made easy
• Warm inflation with a heavy QCD axion
• Revisiting Isocurvature Bounds on the Minimal QCD Axion
• Primordial Black Holes Dark Matter and Secondary Gravitational Waves from Warm Higgs-G Inflation
• Evolution of coupled scalar perturbations through smooth reheating. I. Dissipative regime
• On Sphaleron Heating in the Presence of Fermions
• Non-Gaussianity in the warm k-inflation
• Evolution of coupled scalar perturbations through smooth reheating. II. Thermal fluctuation regime
• CMB bispectrum constraints on DHOST inflation
• Witten-O'Raifeartaigh potential revisited in the context of Warm Inflation
• Primordial non-Gaussianity in noncanonical warm inflation with nonminimal derivative coupling
• Not So Minimal Warm Inflation
• AliCPT Sensitivity to Cosmic Reheating
• Classical equipartition dynamics between axions and non-Abelian gauge fields