%0 Journal Article
%@holdercode {isadg {BR SPINPE} ibi 8JMKD3MGPCW/3DT298S}
%@nexthigherunit 8JMKD3MGPCW/3ETR8EH
%@archivingpolicy denypublisher denyfinaldraft24
%@usergroup administrator
%@usergroup banon
%@usergroup vinicius
%3 Correlated mixture between.pdf
%B Physica A: Statistical Mechanics and its Applications
%@dissemination WEBSCI; PORTALCAPES; COMPENDEX.
%X This work presents a reduced chi(nu)(2) test to search for non-Gaussian signals in the cosmic microwave background radiation (CMBR) TT power spectrum of recent CMBR data, Wilkinson Anisotropy Microwave Probe, Arcminute Cosmology Bolometer Array Receiver, and Cosmic Background Imager data sets, assuming a mixed density field including adiabatic and isocurvature fluctuations. We assume a skew positive mixed model with adiabatic inflation perturbations plus additional isocurvature perturbations possibly produced by topological defects. The joint probability distribution used in this context is a weighted combination of Gaussian and non-Gaussian random fields. Results from simulations of CMBR temperature for the mixed field show a distinct signature in CMB power spectrum for very small deviations (similar to0.1%) from a pure Gaussian field, and can be used as a direct test for the nature of primordial fluctuations. A reduced chi(nu)(2) test applied on the most recent CMBR observations reveals that an isocurvature fluctuations field is not ruled out and indeed permits a very good description for a flat geometry Lambda-CDM Universe, chi(930)(2)similar to1.5, rather than the simple inflationary standard model with chi(930)(2)similar to2.3. This result may looks is particular discrepant with the reduced chi(2) of 1.07 obtained with the same model in Spergel et al. [Astrophys. J. 148, 175 (2003)] for temperature only, however, our work is restricted to a region of the parameter space that does not include the best fit model for TT only of Spergel et al.. .
%8 FEB
%N 4
%T Correlated mixture between adiabatic and isocurvature fluctuations and recent CMB observations
%K PROBE WMAP OBSERVATIONS, COSMOLOGICAL PARAMETERS, INFLATIONARY UNIVERSE, POWER SPECTRUM, GAUSSIANITY.
%@secondarytype PRE PI
%@group DAS-INPE-MCT-BR
%@copyholder SID/SCD
%@secondarykey INPE-13070-PRE/8334
%@issn 0378-4371
%2 sid.inpe.br/iris@1916/2005/12.21.12.50.10
%@affiliation Instituto Nacional de Pesquisas Espaciais, Divisão de Astrofísica (INPE, DAS),
%@language English
%P Art. No. 043501
%4 sid.inpe.br/iris@1916/2005/12.21.12.50
%D 2005
%V 71
%A Andrade, Ana Paula de Almeida,
%A Wuensche, Carlos  Alexandre,
%A Ribeiro, André Luís Batista,
%@area CEA