Evidence of Quasi-linear Super-Structures in the Cosmic Microwave Background and Galaxy Distribution - Astrophysics > Cosmology and Nongalactic AstrophysicsReportar como inadecuado




Evidence of Quasi-linear Super-Structures in the Cosmic Microwave Background and Galaxy Distribution - Astrophysics > Cosmology and Nongalactic Astrophysics - Descarga este documento en PDF. Documentación en PDF para descargar gratis. Disponible también para leer online.

Abstract: Recent measurements of hot and cold spots on the cosmic microwave backgroundCMB sky suggest a presence of super-structures on >100 h^{-1}Mpc scales. Wedevelop a new formalism to estimate the expected amplitude of temperaturefluctuations due to the integrated Sachs-Wolfe ISW effect from prominentquasi-linear structures. Applying the developed tools to the observed ISWsignals from voids and clusters in catalogs of galaxies at redshifts z<1, wefind that they indeed imply a presence of quasi-linear super-structures with acomoving radius 100~300 h^{-1}Mpc and a density contrast ~O0.1. We find thatthe observed ISW signals are at odd with the concordant \Lambda cold darkmatter CDM model that predicts Gaussian primordial perturbations at equal toor larger than 3 sigma level. We also confirm that the mean temperature aroundthe CMB cold spot in the southern Galactic hemisphere filtered by acompensating top-hat filter deviates from a mean value at ~3 sigma level,implying that a quasi-linear supervoid or an underdensity region surrounded bya massive wall may reside at low redshifts z<0.3 and the actual angular size16^\circ-17^\circ may be larger than the apparent size 4^\circ-10^\circdiscussed in literature. Possible solutions are briefly discussed.



Autor: Kaiki Taro Inoue, Nobuyuki Sakai, Kenji Tomita

Fuente: https://arxiv.org/







Documentos relacionados