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arXiv · 1405.7317

CMB Hemispherical Asymmetry: Long Mode Modulation and non-Gaussianity

Mohammad Hossein Namjoo·Ali Akbar Abolhasani·Shant Baghram·Hassan Firouzjahi
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Abstract

The observed hemispherical asymmetry in CMB map can be explained by modulation from a long wavelength super horizon mode which non-linearly couples to the CMB modes. We address the criticism in [1] about the role of non-Gaussianities in squeezed and equilateral configurations in generating hemispherical asymmetry from the long mode modulation. We stress that the modulation is sensitive to the non-Gaussianity in the squeezed limit. In addition, we demonstrate the validity of our approach in providing a consistency condition relating the amplitude of dipole asymmetry to f_{NL} in the squeezed limit.

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Mohammad Hossein Namjoo, Ali Akbar Abolhasani, Shant Baghram, Hassan Firouzjahi. 2014-08-04. CMB Hemispherical Asymmetry: Long Mode Modulation and non-Gaussianity. https://doi.org/10.1088/1475-7516%2F2014%2F08%2F002

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