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@MastersThesis{Fornasa:2018:EsReBu,
               author = "Fornasa, Pietra Rafaela",
                title = "Estudo da rela{\c{c}}{\~a}o entre buracos negros primordiais e 
                         as ondas gravitacionais detectadas pelo LIGO",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2018",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2018-03-02",
             keywords = "buracos negros primordiais, LIGO, mat{\'e}ria escura, ondas 
                         gravitacionais, buraco negro, primordial black holes, LIGO, dark 
                         matter, gravitational waves, black hole.",
             abstract = "A radia{\c{c}}{\~a}o gravitacional {\'e} prevista pela Teoria 
                         da Relatividade Geral de Einstein como uma solu{\c{c}}{\~a}o 
                         ondulat{\'o}ria para as Equa{\c{c}}{\~o}es de Campo. Somente em 
                         2015 foi comprovada direta e observacionalmente a exist{\^e}ncia 
                         dessas perturba{\c{c}}{\~o}es no espa{\c{c}}otempo, 
                         atrav{\'e}s da detec{\c{c}}{\~a}o de ondas gravitacionais pelos 
                         interfer{\^o}metros dos observat{\'o}rios LIGO (Laser 
                         Interferometer Gravitational Waves Observatory). Essas ondas 
                         gravitacionais foram geradas na coalesc{\^e}ncia de dois buracos 
                         negros de alta massa e o evento foi nomeado GW150914. A massa 
                         desses buracos negros intrigou a comunidade cient{\'{\i}}fica 
                         uma vez que, da evolu{\c{c}}{\~a}o estelar, n{\~a}o se esperam 
                         massas muito acima de 15 massas solares. Levantou-se ent{\~a}o a 
                         seguinte quest{\~a}o: Qual a origem desses buracos negros? 
                         Buscando responder essa quest{\~a}o foi desenvolvida uma 
                         an{\'a}lise estat{\'{\i}}stica a partir da fun{\c{c}}{\~a}o 
                         de distribui{\c{c}}{\~a}o da massa dos buracos negros detectados 
                         pelo LIGO. Utilizando como priors uma distribui{\c{c}}{\~a}o 
                         log-normal (modelo Aflleck-Dine) e uma lei de pot{\^e}ncia, foi 
                         desenvolvido um m{\'e}todo para estudar qual {\'e} o modelo mais 
                         favor{\'a}vel para explicar a origem desses buracos negros sendo 
                         que a metodologia feita para esse estudo seguiu uma 
                         estat{\'{\i}}stica Bayesiana. Ap{\'o}s o c{\'a}lculo da 
                         m{\'a}xima verossimilhan{\c{c}}a o modelo Affleck-Dine se 
                         mostrou levemente favor{\'a}vel indicando que esses dois modelos 
                         (Aflleck-Dine e lei de pot{\^e}ncia) s{\~a}o consistentes e 
                         poderiam explicar a origem desses eventos. {\'E} necess{\'a}rio 
                         um maior n{\'u}mero de eventos para distinguir exatamente as duas 
                         curvas e definir qual modelo descreve melhor e, caso o modelo 
                         primordial prevale{\c{c}}a, analisar qual a 
                         contribui{\c{c}}{\~a}o desses buracos negros para a mat{\'e}ria 
                         escura do Universo. ABSTRACT: Gravitational radiation is predicted 
                         by Einsteins Theory of General Relativity as a wave solution for 
                         its Field Equation. But only in 2015 was verified directly and 
                         observationally the existence of these perturbations in spacetime, 
                         through the detection of gravitational waves by LIGO. The 
                         gravitational waves were generated in the coalescence of two high 
                         masses black holes and the event was named GW150914. Their 
                         estimated masses have intrigued the scientific community since 
                         they were not expected by stellar evolution which black holes have 
                         masses higher than 15 solar masses. A new question has raised from 
                         such detections: What is the origin of those black holes? Trying 
                         to answer this question, a statistical analysis was developed to 
                         from the mass distribution function of the black holes detected by 
                         the LIGO. Using as priors a log-normal distribution (Aflleck-Dine 
                         model) and a power law, a method was developed to study which 
                         model is the most probable to explain the origin of such black 
                         holes being that the methodology made for that study followed a 
                         Bayesian statistic. After calculating the maximum likelihood, the 
                         Affleck-Dine model was slightly favorable indicating that these 
                         two models are consistent and could explain the origin of these 
                         events. A greater number of events is required to distinguish 
                         exactly the two curves and to define which model is the best to 
                         describes and, if the primordial model prevails, to analyze the 
                         contribution of those black holes to the dark matter of the 
                         Universe.",
            committee = "Ara{\'u}jo, Jos{\'e} Carlos Neves de (presidente) and Costa, 
                         C{\'e}sar Augusto (presidente) and Souza, Carlos Alexandre 
                         Wuensche de and Alves, M{\'a}rcio Eduardo da Silva",
         englishtitle = "Study of the relationship between primordial black holes and the 
                         gravitational waves detected by LIGO",
             language = "pt",
                pages = "95",
                  ibi = "8JMKD3MGP3W34R/3QN2DG2",
                  url = "http://urlib.net/rep/8JMKD3MGP3W34R/3QN2DG2",
           targetfile = "publicacao.pdf",
        urlaccessdate = "28 nov. 2020"
}


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