Density perturbations from both the inflaton and the curvaton

Abstract

We consider a supersymmetric grand unified model which leads to hybrid inflation and solves the strong CP and mu problems via a Peccei-Quinn symmetry, with the Peccei-Quinn field acting as a curvaton generating together with the inflaton the curvature perturbation. The model yields an isocurvature perturbation too of mixed correlation with the adiabatic one. Two choices of parameters are confronted with the Wilkinson microwave anisotropy probe and other cosmic microwave background radiation data. For the choice giving the best fitting, the curvaton contribution to the amplitude of the adiabatic perturbation must be smaller than 67% at 95% confidence level and the best-fit power spectra are dominated by the adiabatic inflaton contribution. This case is disfavored relative to the pure inflaton scale-invariant case with odds of 50 to 1. For the second choice, the adiabatic mode is dominated by the curvaton, but this case is strongly disfavored relative to the pure inflaton case (with odds of 10^7 to 1). Thus, in this model, the perturbations must be dominated by the adiabatic component from the inflaton.

Talk given at the Workshop "The density perturbation in the universe", 25-26 June 2004, Athens, Greece (to appear in the proceedings), 12 pages including 4 figures, uses espcrc2.sty

References in corpus (4)

• Constraints on a mixed inflaton and curvaton scenario for the generation of the curvature perturbation
• Constraints on isocurvature models from the WMAP first-year data
• Correlated adiabatic and isocurvature CMB fluctuations in the wake of the WMAP
• Bounds on CDM and neutrino isocurvature perturbations from CMB and LSS data

Cited by in corpus (6)

• Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Interpretation
• Modular inflation and the orthogonal axion as curvaton
• Constraints on scalar and tensor perturbations in phenomenological and two-field inflation models: Bayesian evidences for primordial isocurvature and tensor modes
• Inflation at the TeV scale with a PNGB curvaton
• Cosmological Properties of a Gauged Axion
• Particle Physics Approach to Dark Matter