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Title: Large scale anisotropic bias from primordial non-Gaussianity

Abstract

In this work we study the large scale structure bias in models of anisotropic inflation. We use the Peak Background Splitting method in Excursion Set Theory to find the scale-dependent bias. We show that the amplitude of the bias is modified by a direction-dependent factor. In the specific anisotropic inflation model which we study, the scale-dependent bias vanishes at leading order when the long wavelength mode in squeezed limit is aligned with the anisotropic direction in the sky. We also extend the scale-dependent bias formulation to the general situations with primordial anisotropy. We find some selection rules indicating that some specific parts of a generic anisotropic bispectrum is picked up by the bias parameter. We argue that the anisotropic bias is mainly sourced by the angle between the anisotropic direction and the long wavelength mode in the squeezed limit.

Authors:
;  [1];  [2]
  1. School of Astronomy, Institute for Research in Fundamental Sciences (IPM), P.O. Box 19395-5531, Tehran (Iran, Islamic Republic of)
  2. School of Physics, Institute for Research in Fundamental Sciences (IPM), P.O. Box 19395-5531, Tehran (Iran, Islamic Republic of)
Publication Date:
OSTI Identifier:
22282740
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2013; Journal Issue: 08; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; AMPLITUDES; ANISOTROPY; COSMOLOGY; INFLATIONARY UNIVERSE; INFLATONS; SELECTION RULES; SET THEORY; WAVELENGTHS

Citation Formats

Baghram, Shant, Firouzjahi, Hassan, and Namjoo, Mohammad Hossein, E-mail: baghram@ipm.ir, E-mail: mh.namjoo@ipm.ir, E-mail: firouz@ipm.ir. Large scale anisotropic bias from primordial non-Gaussianity. United States: N. p., 2013. Web. doi:10.1088/1475-7516/2013/08/048.
Baghram, Shant, Firouzjahi, Hassan, & Namjoo, Mohammad Hossein, E-mail: baghram@ipm.ir, E-mail: mh.namjoo@ipm.ir, E-mail: firouz@ipm.ir. Large scale anisotropic bias from primordial non-Gaussianity. United States. doi:10.1088/1475-7516/2013/08/048.
Baghram, Shant, Firouzjahi, Hassan, and Namjoo, Mohammad Hossein, E-mail: baghram@ipm.ir, E-mail: mh.namjoo@ipm.ir, E-mail: firouz@ipm.ir. 2013. "Large scale anisotropic bias from primordial non-Gaussianity". United States. doi:10.1088/1475-7516/2013/08/048.
@article{osti_22282740,
title = {Large scale anisotropic bias from primordial non-Gaussianity},
author = {Baghram, Shant and Firouzjahi, Hassan and Namjoo, Mohammad Hossein, E-mail: baghram@ipm.ir, E-mail: mh.namjoo@ipm.ir, E-mail: firouz@ipm.ir},
abstractNote = {In this work we study the large scale structure bias in models of anisotropic inflation. We use the Peak Background Splitting method in Excursion Set Theory to find the scale-dependent bias. We show that the amplitude of the bias is modified by a direction-dependent factor. In the specific anisotropic inflation model which we study, the scale-dependent bias vanishes at leading order when the long wavelength mode in squeezed limit is aligned with the anisotropic direction in the sky. We also extend the scale-dependent bias formulation to the general situations with primordial anisotropy. We find some selection rules indicating that some specific parts of a generic anisotropic bispectrum is picked up by the bias parameter. We argue that the anisotropic bias is mainly sourced by the angle between the anisotropic direction and the long wavelength mode in the squeezed limit.},
doi = {10.1088/1475-7516/2013/08/048},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 08,
volume = 2013,
place = {United States},
year = 2013,
month = 8
}
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