NonGaussianity and largescale structure in a twofield inflationary model
Abstract
Singlefield inflationary models predict nearly Gaussian initial conditions, and hence a detection of nonGaussianity would be a signature of the more complex inflationary scenarios. In this paper we study the effect on the cosmic microwave background and on largescale structure from primordial nonGaussianity in a twofield inflationary model in which both the inflaton and curvaton contribute to the density perturbations. We show that in addition to the previously described enhancement of the galaxy bias on large scales, this setup results in largescale stochasticity. We provide joint constraints on the local nonGaussianity parameter ftilde{sub NL} and the ratio {xi} of the amplitude of primordial perturbations due to the inflaton and curvaton using WMAP and Sloan Digital Sky Survey data.
 Authors:
 Caltech M/C 35017, Pasadena, California 91125 (United States)
 Brookhaven National Laboratory, Upton, New York 11973 (United States)
 Publication Date:
 OSTI Identifier:
 21420936
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 82; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevD.82.043531; (c) 2010 American Institute of Physics
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; AMPLITUDES; DENSITY; DETECTION; DISTURBANCES; GALAXIES; GAUSSIAN PROCESSES; INFLATIONARY UNIVERSE; PERTURBATION THEORY; RELICT RADIATION; COSMOLOGICAL MODELS; ELECTROMAGNETIC RADIATION; MATHEMATICAL MODELS; MICROWAVE RADIATION; PHYSICAL PROPERTIES; RADIATIONS
Citation Formats
Tseliakhovich, Dmitriy, Hirata, Christopher, and Slosar, Anze. NonGaussianity and largescale structure in a twofield inflationary model. United States: N. p., 2010.
Web. doi:10.1103/PHYSREVD.82.043531.
Tseliakhovich, Dmitriy, Hirata, Christopher, & Slosar, Anze. NonGaussianity and largescale structure in a twofield inflationary model. United States. doi:10.1103/PHYSREVD.82.043531.
Tseliakhovich, Dmitriy, Hirata, Christopher, and Slosar, Anze. 2010.
"NonGaussianity and largescale structure in a twofield inflationary model". United States.
doi:10.1103/PHYSREVD.82.043531.
@article{osti_21420936,
title = {NonGaussianity and largescale structure in a twofield inflationary model},
author = {Tseliakhovich, Dmitriy and Hirata, Christopher and Slosar, Anze},
abstractNote = {Singlefield inflationary models predict nearly Gaussian initial conditions, and hence a detection of nonGaussianity would be a signature of the more complex inflationary scenarios. In this paper we study the effect on the cosmic microwave background and on largescale structure from primordial nonGaussianity in a twofield inflationary model in which both the inflaton and curvaton contribute to the density perturbations. We show that in addition to the previously described enhancement of the galaxy bias on large scales, this setup results in largescale stochasticity. We provide joint constraints on the local nonGaussianity parameter ftilde{sub NL} and the ratio {xi} of the amplitude of primordial perturbations due to the inflaton and curvaton using WMAP and Sloan Digital Sky Survey data.},
doi = {10.1103/PHYSREVD.82.043531},
journal = {Physical Review. D, Particles Fields},
number = 4,
volume = 82,
place = {United States},
year = 2010,
month = 8
}

Singlefield inflationary models predict nearly Gaussian initial conditions, and hence a detection of nonGaussianity would be a signature of the more complex inflationary scenarios. In this paper we study the effect on the cosmic microwave background and on largescale structure from primordial nonGaussianity in a twofield inflationary model in which both the inflaton and curvaton contribute to the density perturbations. We show that in addition to the previously described enhancement of the galaxy bias on large scales, this setup results in largescale stochasticity. We provide joint constraints on the local nonGaussianity parameter f*{sub NL} and the ratio {zeta} of themore »

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