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@MastersThesis{Assis:2016:ExOnMH,
               author = "Assis, Adam Smith Gontijo Brito de",
                title = "Excita{\c{c}}{\~a}o de ondas MHD atrav{\'e}s da emiss{\~a}o de 
                         ondas gravitacionais produzidas por bin{\'a}rias de estrelas de 
                         n{\^e}utrons",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2016",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2016-02-22",
             keywords = "ondas gravitacionais, estrelas de n{\^e}utrons, ondas 
                         magnetohidrodin{\^a}micas, explos{\~o}es de raios gamma, ondas 
                         eletromagn{\'e}ticas, gravitational waves, neutron stars, 
                         magnetohydrodynamic waves, gamma ray bursts, electromagnetic 
                         waves.",
             abstract = "A coalesc{\^e}ncia de sistemas de bin{\'a}rias de n{\^e}utrons 
                         (ENs) produz quantidade significativa de ondas gravitacionais 
                         (OGs) e s{\~a}o fontes prop{\'{\i}}cias a serem observadas 
                         pelos detectores avan{\c{c}}ados terrestres (por exemplo, 
                         \emph{Advanced} LIGO), na faixa espectral de 10 Hz a 1 kHz. As 
                         ENs tamb{\'e}m possuem contrapartida observacional, no espectro 
                         eletromagn{\'e}tico, uma vez que est{\~a}o relacionadas com os 
                         eventos de \emph{Gamma-Ray Bursts} (GRBs) de curta 
                         dura{\c{c}}{\~a}o (t<\$\sim\$2s). Explos{\~o}es de 
                         raios-\$\gamma\$ s{\~a}o os eventos mais violentos conhecidos 
                         desde o nascimento do universo, correspondendo a uma luminosidade 
                         de 10\$^{51}\$ - 10\$^{52}\$ erg s\$^{\−1}\$. 
                         Emiss{\~a}o gravitacional, entretanto, ainda n{\~a}o foi 
                         detectada diretamente. A primeira evid{\^e}ncia indireta foi 
                         obtida com a bin{\'a}ria de pulsares PSR 1913+16, descoberta por 
                         Hulse \\& Taylor (1974). Contudo, devido aos intensos campos 
                         magn{\'e}ticos de ENs e, consequentemente, ao plasma fortemente 
                         magnetizado circundante a essas fontes de OGs, os modos 
                         Alfv{\'e}n e magneto-ac{\'u}stico de ondas 
                         magnetohidrodin{\^a}micas (MHD) s{\~a}o excitados pelas 
                         polariza{\c{c}}{\~o}es das OGs, x e +, respectivamente. Por sua 
                         vez, as ondas MHD excitadas interagem com o plasma do sistema, 
                         principalmente, por espalhamento Compton Inverso, que pode levar 
                         {\`a} gera{\c{c}}{\~a}o de harm{\^o}nicos maiores dos modos 
                         originais e se tornarem vis{\'{\i}}veis no dom{\'{\i}}nio 
                         eletromagn{\'e}tico, sugerindo assim um mecanismo alternativo 
                         para detec{\c{c}}{\~a}o indireta de OGs. Este trabalho estuda a 
                         intera{\c{c}}{\~a}o da onda gravitacional com as ondas 
                         Alf{\'e}n e magnetoss{\^o}nicas, durante a fase spiral da 
                         coalesc{\^e}ncia (frequ{\^e}ncia da OG, \$\omega\$g, num 
                         intervalo de [300 - 1500]Hz) de sistemas bin{\'a}rios de estrelas 
                         de n{\^e}utrons. At{\'e} ent{\~a}o, tal acoplamento tinha sido 
                         estudado para um sistema de ENs pr{\'o}ximo ao merger 
                         (\$\omega\$g \$\approx\$ 1.5kHz). Discutimos 
                         diferen{\c{c}}as das abordagens e, em seguida, estimamos a 
                         quantidade de energia transferida entre as ondas, nos permitindo 
                         identificar, num trabalho posterior, se a energia depositada pode 
                         ser um mecanismo alternativo de igni{\c{c}}{\~a}o da Fireball de 
                         GRB. ABSTRACT: The coalescence of binary neutron systems (NSs) 
                         produces a significant amount of gravitational waves (GWs) and are 
                         favourable sources to be observed by the ground advanced detectors 
                         (eg, Advanced LIGO) in the spectral range from 10 Hz - 1 kHz. The 
                         NSs also have observational contrast, the electromagnetic 
                         spectrum, as long as they are related to the events of short 
                         Gamma-Ray Bursts (GRBs) (t<\$\sim\$2s). The GRBs are the most 
                         violent events known since the birth of the universe, 
                         corresponding to a luminosity of 10\$^{51}\$ - 10\$^{52}\$ erg 
                         s\$^{-1}\$. Gravitational emission, however, has not yet been 
                         detected directly. The indirect evidence was first obtained with 
                         the binary pulsar PSR 1913+16, discovered by Hulse \\& Taylor 
                         (1974). However, due to the intense magnetic fields NSs and hence 
                         the strongly magnetized plasma surrounding these sources of GWs, 
                         the Alfv{\'e}n modes and magneto-acoustic magnetohydrodynamic 
                         waves (MHD) are excited by the polarizations of the GWs, x and +, 
                         respectively. The MHD wave excited in turn interacts with the 
                         plasma system, mainly by inverse Compton scattering, which can 
                         lead to the generation of higher harmonics of the original mode 
                         and become visible in the electromagnetic domain, suggesting an 
                         alternative mechanism for indirect detection GWs. This work 
                         studies the interaction of gravitational waves with Alfv{\'e}n 
                         and magneto-sonic waves during the spiral-phase of coalescence 
                         (frequency GW, \$\omega\$g in a range of [300 \− 1500] 
                         Hz) of binary neutron star systems. Until then such engagement had 
                         been studied only for NSs system near the merger (\$\omega\$g 
                         \$\approx\$ 1.5 kHz). We discuss the differences in the 
                         approaches and then estimate the amount of energy transferred 
                         between the waves, allowing us to identify, in a subsequent work, 
                         if the energy deposited can be an alternative mechanism for the 
                         ignition fireball of GRB.",
            committee = "Aguiar, Odylio Denys de (presidente) and Miranda, Oswaldo Duarte 
                         (orientador) and Alves, Maria Virg{\'{\i}}nia and Oliveira, 
                         Manuel M{\'a}ximo Bastos Malheiro de",
           copyholder = "SID/SCD",
         englishtitle = "Excitation of MHD waves by gravitational waves generated by 
                         neutron star binary systems",
             language = "pt",
                pages = "165",
                  ibi = "8JMKD3MGP3W34P/3L4RUUL",
                  url = "http://urlib.net/rep/8JMKD3MGP3W34P/3L4RUUL",
           targetfile = "publicacao.pdf",
        urlaccessdate = "28 nov. 2020"
}


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