Abstract
Supergravity corrections due to the energy density of a right-handed sneutrino can generate a negative mass squared for the inflaton, flattening the inflaton potential and reducing the spectral index and inflaton energy density. For the case of -term hybrid inflation, we show that the spectral index can be lowered from the conventional value to a value within the range favored by the latest WMAP analysis, . The modified energy density is consistent with nonobservation of cosmic strings in the CMB if . The WMAP lower bound on the spectral index implies that the -term cosmic string contribution may be very close present CMB limits, contributing at least 5% to the CMB multipoles.
- Received 1 June 2006
DOI:https://doi.org/10.1103/PhysRevD.74.063510
©2006 American Physical Society