Optimal constraint on g{sub NL} from CMB

Journal Article · Sun Sep 01 00:00:00 EDT 2013 · Journal of Cosmology and Astroparticle Physics

DOI:https://doi.org/10.1088/1475-7516/2013/09/002· OSTI ID:22282749

Sekiguchi, Toyokazu; Sugiyama, Naoshi ^[1]

---

1. Department of Physics and Astrophysics, Nagoya University, Nagoya 464-8602 (Japan)

An optimal method to constrain the non-linearity parameter g{sub NL} of the local-type non-Gaussianity from CMB data is proposed. Our optimal estimator for g{sub NL} is separable and can be efficiently computed in real space. Combining the exact filtering of CMB maps with the full covariance matrix, our method allows us to extract cosmological information from observed data as much as possible and obtain a tighter constraint on g{sub NL} than previous studies. Applying our method to the WMAP 9-year data, we obtain the constraint g{sub NL} = (−3.3±2.2) × 10{sup 5}, which is a few times tighter than previous ones. We also make a forecast for PLANCK data by using the Fisher matrix analysis.

• OSTI ID: 22282749
• Journal Information: Journal of Cosmology and Astroparticle Physics, Vol. 2013, Issue 09; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 1475-7516
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ASTROPHYSICS
COSMOLOGY
LIMITING VALUES
MATRICES
RELICT RADIATION
SPACE