Analysis of CMB maps with 2D wavelets

We consider the 2D wavelet transform with two scales to study sky maps of temperature anisotropies in the cosmic microwave background radiation (CMB). We apply this technique to simulated maps of small sky patches of size 12.8∘×12.8∘ and 1.5′×1.5′ pixels. The relation to the standard approach, based...

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Detalles Bibliográficos
Autores: Sanz, J. L., Barreiro, R. Belén, Cayón, Laura, Martínez-González, Enrique, Ruiz, G. A., Díaz, F. J., Argüeso, Francisco, Silk, Joseph, Toffolatti, Luigi
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:1999
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/384652
Acceso en línea:http://hdl.handle.net/10261/384652
Access Level:acceso abierto
Palabra clave:Cosmology: cosmic microwave background
Methods: data analysis
Descripción
Sumario:We consider the 2D wavelet transform with two scales to study sky maps of temperature anisotropies in the cosmic microwave background radiation (CMB). We apply this technique to simulated maps of small sky patches of size 12.8∘×12.8∘ and 1.5′×1.5′ pixels. The relation to the standard approach, based on the Cl′s, is established through the introduction of the scalogram. We consider temperature fluctuations derived from standard, open and flat-Λ Cold Dark Matter (CDM) models. We analyze CMB anisotropies maps plus uncorrelated Gaussian noise (uniform and non-uniform) at different S/N levels. We explore in detail the denoising of such maps and compare the results with other techniques already proposed in the literature. Wavelet methods provide a good reconstruction of the image and power spectrum. Moreover, they are faster than previously proposed methods.