On the inpainting of incomplete CMB sky maps: Estudio sobre el inpainting de cielos incompletos del FCM

ABSTARCT: The aim of this project is to develop a new inpainting technique for masked Cosmic Microwave Background (CMB) sky maps. Due to the presence of foreground emissions, the CMB is usually recovered by using component separation methods, which allow us to separate the CMB signal from this foreg...

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Detalles Bibliográficos
Autor: Álvarez Ortega, Diego
Tipo de recurso: tesis de maestría
Fecha de publicación:2022
País:España
Institución:Universidad de Cantabria (UC)
Repositorio:UCrea Repositorio Abierto de la Universidad de Cantabria
Idioma:inglés
OAI Identifier:oai:repositorio.unican.es:10902/29423
Acceso en línea:https://hdl.handle.net/10902/29423
Access Level:acceso abierto
Palabra clave:Cosmology
Cosmic Microwave Background
Inpainting
Image processing
Cosmología
Fondo Cósmico de Microondas
Rellenado
Procesamiento de imágenes
Descripción
Sumario:ABSTARCT: The aim of this project is to develop a new inpainting technique for masked Cosmic Microwave Background (CMB) sky maps. Due to the presence of foreground emissions, the CMB is usually recovered by using component separation methods, which allow us to separate the CMB signal from this foreground contamination. However, there are some regions (e.g the galactic plane, point sources) in which the signal recovery is so poor that it needs to be masked. Inpainting techniques try to fill in this masked region with random signals that are statistically coherent with the rest of the observed sky. In order to do so, in this work we have proposed a novel inpainting technique, the wavelet diffuse inpainting. This method tries to extend an existing procedure, called diffuse inpainting, by applying a multiresolution approach using a type of wavelet known as HEALPix wavelet. This allows us to improve the range of angular scales at which the inpainting is effective, as well as to reduce computing times. For this study, we have characterized the optimal inpainting parameters of this new method and the diffuse inpainting it is based on. To test the efficacy of the technique, we have compared it with the diffuse inpainting at three levels, visual sky map reconstruction, angular power spectra recovery, and presence of correlations between different angular scales. Furthermore, some preliminary results have been obtained by applying this technique to Planck data.