A Bayesian estimate of the CMB-large-scale structure cross-correlation

Evidences for late-time acceleration of the Universe are provided by multiple probes, such as Type Ia supernovae, the cosmic microwave background (CMB) and large-scale structure (LSS). In this work, we focus on the integrated Sachs--Wolfe (ISW) effect, i.e., secondary CMB fluctuations generated by evolving gravitational potentials due to the transition between, e.g., the matter and dark energy (DE) dominated phases. Therefore, assuming a flat universe, DE properties can be inferred from ISW detections. We present a Bayesian approach to compute the CMB--LSS cross-correlation signal. The method is based on the estimate of the likelihood for measuring a combined set consisting of a CMB temperature and a galaxy contrast maps, provided that we have some information on the statistical properties of the fluctuations affecting these maps. The likelihood is estimated by a sampling algorithm, therefore avoiding the computationally demanding techniques of direct evaluation in either pixel or harmonic space. As local tracers of the matter distribution at large scales, we used the Two Micron All Sky Survey (2MASS) galaxy catalog and, for the CMB temperature fluctuations, the ninth-year data release of the Wilkinson Microwave Anisotropy Probe (WMAP9). The results show a dominance of cosmic variance over the weak recovered signal, due mainly to the shallowness of the catalog used, with systematics associated with the sampling algorithm playing a secondary role as sources of uncertainty. When combined with other complementary probes, the method presented in this paper is expected to be a useful tool to late-time acceleration studies in cosmology.Comment: 21 pages, 15 figures, 4 tables. We extended the previous analyses including WMAP9 Q, V and W channels, besides the ILC map. Updated to match accepted ApJ versio

The dipole anisotropy of WISE x SuperCOSMOS number counts

We probe the isotropy of the Universe with the largest all-sky photometric redshift dataset currently available, namely WISE~$\times$~SuperCOSMOS. We search for dipole anisotropy of galaxy number counts in multiple redshift shells within the $0.10 < z < 0.35$ range, for two subsamples drawn from the same parent catalogue. Our results show that the dipole directions are in good agreement with most of the previous analyses in the literature, and in most redshift bins the dipole amplitudes are well consistent with $\Lambda$CDM-based mocks in the cleanest sample of this catalogue. In the $z<0.15$ range, however, we obtain a persistently large anisotropy in both subsamples of our dataset. Overall, we report no significant evidence against the isotropy assumption in this catalogue except for the lowest redshift ranges. The origin of the latter discrepancy is unclear, and improved data may be needed to explain it.Comment: 5 pages, 4 figures, 2 tables. Published in MNRA

Recomendação sobre o uso do ultra-som para diagnóstico de prenhez de bovinos e eqüinos.

O diagnostico da prenhez de bovinos e equinos e de extrema importancia economica, porque viabiliza o descarte dos improdutivos e contribui, dessa forma, para minimizar os custos de producao. A idade do feto que permite o diagnostico influi no manejo do rebanho, onde as femeas prenhez sao separadas em pastos de melhor qualidade, pois representam o componente produtivo do rebanho. Assim, quanto mais cedo ocorrer o diagnostico, maior a oportunidade para dar a esses animais o tratamento adequado. O metodo tradicional de deteccao de prenhez, chamado de toque retal, requer que o perito faca a apalpacao nos cornos uterinos, atraves das porcoes finais do reto, para verificar alteracoes fisiologicas de volume e textura no utero e vesicula amniotica. As alteracoes constatadas levam o perito a concluir se o animal esta ou nao prenhe. Tal metodo requer um perito altamente treinado; e demorado, so e confiavel apos 60 dias da cobertura em bovinos, e oneroso para o produtor e nao permite saber se o feto esta vivo. Deste modo, uma falsa prenhez diagnosticada pelo metodo tradicional acarreta aumento de gastos para o produtor. O aparelho proposto e construido pela EMBRAPA/CNPDIA e testado em animais do plantel da EMBRAPA/CPPSE, substitui com vantagens os inconvenientes acima mencionados, pois o emprego do ultra-som de ondas continuas e simples, de facil manejo, inocuo para o feto em formacao, proporcionando um trabalho rapido, altamente confiavel e permite concluir se o feto esta vivo ou nao...bitstream/CNPDIA/5007/1/CT01_96.pd