2012/07/31 by Chiaki Hikage, Takahiko Matsubara · 38 citations
Earth and Planetary Sciences · Physics and Astronomy · #Anisotropy #Astrophysics #Bispectrum #CMB cold spot #Cosmic background radiation #Cosmic microwave background #Cosmology and Gravitation Theories #Geophysics and Gravity Measurements #Kurtosis #Mathematical physics #Minkowski space #Non-Gaussianity #Order (exchange) #Physics #Quantum mechanics #Solar and Space Plasma Dynamics #Spectral density #Statistics #Trispectrum #Type (biology) #astro-ph.CO
paper · pdf · doi:10.1111/j.1365-2966.2012.21572.x
published in Monthly Notices of the Royal Astronomical Society 425(3), 2187-2196 (Oxford University Press) · 11 pages, 8 figures, MNRAS accepeted
openalex publication_date 2012/08/27 · arxiv created 2012/09/27 · arxiv updated 2012/09/28 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We analyse non-Gaussianity (NG) due to the primordial bispectrum and trispectrum using cosmic microwave background temperature maps of WMAP 7-year data. We first apply the perturbative formulae of Minkowski functionals (MFs) up to second-order NG derived by Matsubara, which enable us to give limits on cubic NG parametrized with τNL and gNL as well as various types of quadratic NG parametrized with fNL. We find no signature of primordial NG in WMAP 7-year data, but give constraints on the local-type, equilateral-type and orthogonal-type fNL, , and , respectively, and τNL/104 = −7.6 ± 8.7 and gNL/105 = −1.9 ± 6.4. We also find that these constraints are consistent with the limits from skewness and kurtosis parameters which characterize the perturbative corrections of MFs.