Oscillations in the inflaton potential?
We consider a class of inflationary models with small oscillations imprinted on an otherwise smooth inflaton potential. These oscillations are manifest as oscillations in the power spectrum of primordial perturbations, which then give rise to oscillating departures from the standard cosmic microwave background power spectrum. We show that current data from the Wilkinson Microwave Anisotropy Probe constrain the amplitude of a sinusoidal variation in the inflaton potential to have an amplitude less than 3×10^(-5). We anticipate that the smallest detectable such oscillations in Planck will be roughly an order of magnitude smaller, with slight improvements possible with a post-Planck cosmic-variance limited experiment.
Additional Information© 2009 The American Physical Society. Received 4 July 2008; published 3 April 2009. C. P. acknowledges the hospitality of the Moore Center for Theoretical Cosmology and Physics at Caltech. C. P. was supported in part by the Swiss Sunburst Fund and the Royal Astronomical Society; M. K. was supported by the DOE under Grant No. DE-FG03-92-ER40701 and the Gordon and Betty Moore Foundation; and A. R. L. was supported by STFC (UK).
Published - Pahud2009p4458Phys_Rev_D.pdf