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@MastersThesis{Ladislau:2019:AnMePe,
               author = "Ladislau, Samantha Monaliza",
                title = "An{\'a}lises dos mecanismos de perda de energia e os 
                         {\'{\i}}ndices de freamento em pulsares",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2019",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2019-02-26",
             keywords = "Estrela de n{\^e}utrons, pulsares, pulsares isolados, spindown, 
                         {\'{\i}}ndice de frenagem, neutron stars, pulsars, isolated 
                         pulsars, spindown, braking index.",
             abstract = "Estrelas de n{\^e}utrons n{\~a}o-axissim{\'e}tricas e em 
                         r{\'a}pida rota{\c{c}}{\~a}o s{\~a}o candidatas 
                         prop{\'{\i}}cias a serem observadas pelos detectores Einstein 
                         Telescope (ET) e Cosmic Explorer (CE) considerando limites 
                         superiores de produ{\c{c}}{\~a}o de ondas gravitacionais 
                         cont{\'{\i}}nuas por essas fontes. Entretanto, {\'e} 
                         poss{\'{\i}}vel obter previs{\~o}es para a possibilidade de 
                         detec{\c{c}}{\~a}o levando em conta outros mecanismos de perda 
                         de energia em pulsares. Desde o final da d{\'e}cada de 1960, 
                         temos conhecimento de que, embora os pulsares tenham seus 
                         per{\'{\i}}odos de rota{\c{c}}{\~a}o muito est{\'a}veis, eles 
                         n{\~a}o s{\~a}o constantes e apresentam varia{\c{c}}{\~o}es 
                         entre ~ (10\−20\−10\−9) s s\−1. No 
                         {\^a}mbito da pesquisa de spindown dos pulsares, v{\'a}rios 
                         esfor{\c{c}}os t{\^e}m sido feitos para se entender o que leva 
                         esses objetos a desacelerarem, bem como os {\'{\i}}ndices de 
                         frenagem medidos. {\'E} nesse contexto que o presente trabalho 
                         traz uma an{\'a}lise de combina{\c{c}}{\~o}es entre os modelos 
                         de perda de energia por radia{\c{c}}{\~a}o de dipolo 
                         magn{\'e}tico (RDM), por ondas gravitacionais (OGs), por Quantum 
                         Vacuum Friction (QVF) e por vento de part{\'{\i}}culas (VP) e a 
                         consequ{\^e}ncia dessas combina{\c{c}}{\~o}es na 
                         evolu{\c{c}}{\~a}o do {\^a}ngulo de inclina{\c{c}}{\~a}o 
                         magn{\'e}tica () do pulsar, na sua velocidade angular (omega) e 
                         no {\'{\i}}ndice de frenagem (n). Mostramos que tanto QVF como 
                         VP combinados {\`a} RDM s{\~a}o capazes de explicar o menor 
                         {\'{\i}}ndice de frenagem j{\'a} medido n = 0, 9  0, 2, para o 
                         pulsar PSR J1734-3333. Al{\'e}m disso, mostramos como {\'e} a 
                         evolu{\c{c}}{\~a}o acoplada entre rota{\c{c}}{\~a}o e o 
                         {\^a}ngulo de inclina{\c{c}}{\~a}o magn{\'e}tica e 
                         conclu{\'{\i}}mos que o QVF {\'e} respons{\'a}vel por atrasar 
                         o alinhamento do pulsar. Adicionalmente, investigamos como 
                         diferentes valores de massa em pulsares alimentados por 
                         rota{\c{c}}{\~a}o e o movimento de precess{\~a}o influenciam a 
                         amplitude das OGs geradas por tais objetos e qual o potencial de 
                         detec{\c{c}}{\~a}o dessas fontes pela nova gera{\c{c}}{\~a}o 
                         de detectores de OGs. Como resultado, obtivemos que, mesmo numa 
                         perspectiva otimista, considerando pulsares com massas ~ 2,0 M., 
                         essas fontes n{\~a}o seriam detectadas pelo aLIGO se a 
                         deforma{\c{c}}{\~a}o do pulsar for de origem magn{\'e}tica. 
                         J{\'a} no modelo de gera{\c{c}}{\~a}o de OGs por movimento de 
                         precess{\~a}o, obtivemos que em um tempo de 
                         integra{\c{c}}{\~a}o de 1 ano os pulsares Vela e Caranguejo 
                         seriam detectados pelo ET e pelo CE se as ENs tiverem (epsilon) ~~ 
                         10\−5 e wobble angle (alpha) = 0, 1 rad. ABSTRACT: 
                         Non-axisymmetric and fast-spinning neutron stars are suitable 
                         candidates to be observed by the detectors Einstein Telescope (ET) 
                         and Cosmic Explorer (CE) considering upper limits of continuous 
                         gravitational waves production by these sources. However, it is 
                         possible to obtain predictions for the possibility of detection 
                         taking into account other mechanisms of loss of energy in pulsars. 
                         Since the late 1960s, we have learned that although pulsars have 
                         very stable rotation periods, they are not constant and vary (~ 
                         10\−20 \− 10\−9 s s\−1) . In the scope 
                         of pulsar spindown research, several efforts have been made to 
                         understand what causes these objects to decelerate, as well as the 
                         measured braking indices. In this context the present work brings 
                         an analysis of combinations between the energy loss models by 
                         magnetic dipole radiation (MDR), gravitational waves (GW), quantum 
                         vacuum friction (QVF) and particle wind (PW) and the consequence 
                         of these combinations on the evolution of the magnetic inclination 
                         angle , angular velocity and the braking index n. We show that 
                         both QVF and PW combined with MDR are able to explain the lowest 
                         measured braking index (n = 0.9  0.2) for PSR J1734-3333. In 
                         addition, we show the coupled evolution between rotation and 
                         magnetic inclination angle and we conclude that the QVF is 
                         responsible for delaying the alignment of the pulsar. 
                         Additionally, we investigated the effect of different mass values 
                         of rotation powered pulsar (RPP) on the the amplitude of the GW 
                         and we study the possibility of GW generated by RPPs precession 
                         motion being detected by new generation of gravitational wave 
                         detectors. As a result, we obtained that, even in an optimistic 
                         perspective, considering pulsars with masses of 2.0 solar masses, 
                         these sources would not be detected by the aLIGO if the pulsar 
                         deformation is of magnetic origin. In the model of GW generated by 
                         precession motion, we concluded that Vela and Crab pulsars would 
                         be detect in one year of integration by ET and EC with (epsilon) 
                         ~~ 10\−5 and wobble angle (alpha) = 0.1 rad.",
            committee = "Aguiar, Odylio Denys de (presidente) and Ara{\'u}jo, Jos{\'e} 
                         Carlos Neves de (orientador) and Coelho, Jaziel Goulart 
                         (orientador) and Rodrigues, Cl{\'a}udia Vilega and 
                         Magalh{\~a}es, Nadja Sim{\~a}o",
         englishtitle = "Analysis of energy loss mechanisms and pulsars braking indices",
             language = "pt",
                pages = "99",
                  ibi = "8JMKD3MGP3W34R/3SNU35H",
                  url = "http://urlib.net/rep/8JMKD3MGP3W34R/3SNU35H",
           targetfile = "publicacao.pdf",
        urlaccessdate = "23 nov. 2020"
}


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