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Title: Modular Inflation and the Curvaton

Abstract

Supersymmetric Peccei-Quinn models which provide a suitable candidate for the curvaton field are studied. These models also solve the {mu} problem, while generating the Peccei-Quinn scale dynamically. The curvaton is a pseudo Nambu-Goldstone boson corresponding to an angular degree of freedom orthogonal to the axion. Its order parameter increases substantially following a phase transition during inflation.s results in a drastic amplification of the curvaton perturbations. Consequently, these models are able to accommodate low-scale inflation with Hubble parameter at the TeV scale such as modular inflation. We find that modular inflation with the orthogonal axion as curvaton can indeed account for the observations for natural values of the parameters. In particular, the spectral index can easily be made adequately lower than unity in accord with the recent data.

Authors:
 [1]
  1. Physics Division, School of Technology, Aristotle University of Thessaloniki, GR-54124 Thessaloniki (Greece)
Publication Date:
OSTI Identifier:
20900802
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 881; Journal Issue: 1; Conference: CICHEP II: Cairo international conference on high energy physics, Cairo (Egypt), 14-17 Jan 2006; Other Information: DOI: 10.1063/1.2435289; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; AMPLIFICATION; AXIONS; COSMOLOGY; DEGREES OF FREEDOM; INFLATIONARY UNIVERSE; ORDER PARAMETERS; PERTURBATION THEORY; PHASE TRANSFORMATIONS; QUANTUM FIELD THEORY; SUPERSYMMETRY; TEV RANGE 01-10

Citation Formats

Lazarides, George. Modular Inflation and the Curvaton. United States: N. p., 2007. Web. doi:10.1063/1.2435289.
Lazarides, George. Modular Inflation and the Curvaton. United States. doi:10.1063/1.2435289.
Lazarides, George. Fri . "Modular Inflation and the Curvaton". United States. doi:10.1063/1.2435289.
@article{osti_20900802,
title = {Modular Inflation and the Curvaton},
author = {Lazarides, George},
abstractNote = {Supersymmetric Peccei-Quinn models which provide a suitable candidate for the curvaton field are studied. These models also solve the {mu} problem, while generating the Peccei-Quinn scale dynamically. The curvaton is a pseudo Nambu-Goldstone boson corresponding to an angular degree of freedom orthogonal to the axion. Its order parameter increases substantially following a phase transition during inflation.s results in a drastic amplification of the curvaton perturbations. Consequently, these models are able to accommodate low-scale inflation with Hubble parameter at the TeV scale such as modular inflation. We find that modular inflation with the orthogonal axion as curvaton can indeed account for the observations for natural values of the parameters. In particular, the spectral index can easily be made adequately lower than unity in accord with the recent data.},
doi = {10.1063/1.2435289},
journal = {AIP Conference Proceedings},
number = 1,
volume = 881,
place = {United States},
year = {Fri Jan 12 00:00:00 EST 2007},
month = {Fri Jan 12 00:00:00 EST 2007}
}
  • We study a particular supersymmetric realization of the Peccei-Quinn symmetry which provides a suitable candidate for the curvaton field. The class of models considered also solves the {mu} problem, while generating the Peccei-Quinn scale dynamically. The curvaton candidate is a pseudo-Nambu-Goldstone boson corresponding to an angular degree of freedom orthogonal to the axion field. Its order parameter increases substantially following a phase transition during inflation. This results in a drastic amplification of the curvaton perturbations. Consequently, the mechanism is able to accommodate low-scale inflation with Hubble parameter at the TeV scale. Hence, we investigate modular inflation using a string axionmore » field as the inflaton with inflation scale determined by gravity mediated soft supersymmetry breaking. We find that modular inflation with the orthogonal axion as curvaton can indeed account for the observations for natural values of the parameters.« less
  • We consider the effects of the curvaton, late-decaying scalar condensation, to observational constraints on inflation models. From current observations of cosmic density fluctuations, severe constraints on some classes of inflation models are obtained, in particular, on the chaotic inflation with higher-power monomials, the natural inflation, and the new inflation. We study how the curvaton scenario changes (and relaxes) the constraints on these models.
  • No abstract prepared.
  • The curvaton reheating in a tachyonic braneworld inflationary universe model with an exponential potential is studied. We have found that the energy density in the kinetic epoch, has a complicated dependencies of the scale factor. For different scenarios the temperature of reheating is computed, finding an upper limit that lies in the range 10{sup 14}-10{sup 16} GeV.
  • We calculate the quadra-spectrum and quint-spectrum, corresponding to five and six point correlation functions of the curvature perturbation. For single field inflation with standard kinetic term, the quadra-spectrum and quint-spectrum are small, which are suppressed by slow roll parameters. The calculation can be generalized to multiple fields. When there is no entropy perturbation, the quadra-spectrum and quint-spectrum are suppressed as well. With the presence of entropy perturbation, the quadra-spectrum and quint-spectrum can get boosted. We illustrate this boost in the multi-brid inflation model. For the curvaton scenario, the quadra-spectrum and quint-spectrum are also large in the small r limit. Wemore » also calculate representative terms of quadra-spectrum and quint-spectrum for inflation with generalized kinetic terms, and estimate their order of magnitude for quasi-single field inflation.« less