On the future combination of Planck and LiteBIRD data: gravitational lensing effect

ABSTRACT: The main objective of this work is to study how we can combine the data from the Cosmic Microwave Background (CMB) experiments Planck and the upcoming LiteBIRD in order to improve the estimation of the gravitational lensing effect. This effect deffects the CMB photons along their path to u...

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Detalles Bibliográficos
Autor: Ruiz Granda, Miguel
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:10902/29425
Acceso en línea:https://hdl.handle.net/10902/29425
Access Level:acceso abierto
Palabra clave:Cosmic Microwave Background
Cosmology
Weak gravitational lensing
Quadratic estimators
Fondo Cósmico de Microondas
Cosmología
Efecto lente gravitacional débil
Estimadores cuadráticos
Descripción
Sumario:ABSTRACT: The main objective of this work is to study how we can combine the data from the Cosmic Microwave Background (CMB) experiments Planck and the upcoming LiteBIRD in order to improve the estimation of the gravitational lensing effect. This effect deffects the CMB photons along their path to us and it is an important cosmological probe as it traces the distribution of matter in the Universe. Along this work, CMB maps have been simulated taking into account a simplifed experimental framework, including white instrumental noise, limited angular resolution, and partial sky coverage. Using the quadratic estimators from Okamoto & Hu [1], the map of the gravitational lensing potential can be reconstructed from the observed CMB maps. The results provided in this document show that combining both experiments is a great idea because they are complementary. While Planck has measured very precisely CMB temperature, LiteBIRD will measure CMB polarization with an unprecedented precision. Consequently, the estimated full-sky signal-to-noise ratio of the lensing potential for the combination will be of about 130, whereas for each individual experiment is approximately of 86 for Planck and 88 for Lite-BIRD. It implies an improvement of about a 50% in the lensing potential reconstruction when combining both experiments.