15 research outputs found

    Search for gravitational-wave transients associated with magnetar bursts in advanced LIGO and advanced Virgo data from the third observing run

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    Gravitational waves are expected to be produced from neutron star oscillations associated with magnetar giant f lares and short bursts. We present the results of a search for short-duration (milliseconds to seconds) and longduration (∼100 s) transient gravitational waves from 13 magnetar short bursts observed during Advanced LIGO, Advanced Virgo, and KAGRA’s third observation run. These 13 bursts come from two magnetars, SGR1935 +2154 and SwiftJ1818.0−1607. We also include three other electromagnetic burst events detected by FermiGBM which were identified as likely coming from one or more magnetars, but they have no association with a known magnetar. No magnetar giant flares were detected during the analysis period. We find no evidence of gravitational waves associated with any of these 16 bursts. We place upper limits on the rms of the integrated incident gravitational-wave strain that reach 3.6 × 10−²³ Hz at 100 Hz for the short-duration search and 1.1 ×10−²² Hz at 450 Hz for the long-duration search. For a ringdown signal at 1590 Hz targeted by the short-duration search the limit is set to 2.3 × 10−²² Hz. Using the estimated distance to each magnetar, we derive upper limits upper limits on the emitted gravitational-wave energy of 1.5 × 1044 erg (1.0 × 1044 erg) for SGR 1935+2154 and 9.4 × 10^43 erg (1.3 × 1044 erg) for Swift J1818.0−1607, for the short-duration (long-duration) search. Assuming isotropic emission of electromagnetic radiation of the burst fluences, we constrain the ratio of gravitational-wave energy to electromagnetic energy for bursts from SGR 1935+2154 with the available fluence information. The lowest of these ratios is 4.5 × 103

    Formas de Funcionalismo na Sintaxe Functionalism in Syntax

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    Este trabalho procura mostrar que o termo "funcionalismo", frequentemente suposto como uma abordagem única ou uniforme na lingüística, precisa ser compreendida em suas diversas perspectivas. Inicio o trabalho apresentando o contraste conceitual semelhante às de Língua-I e Língua-E, em Chomsky (1986). Tal como na primeira concepção, a língua, na visão funcionalista, pode ser tomada como um modelo abstrato do mecanismo interno da mente responsável pela produção e percepção da língua ou , como na segunda, pode ser entendida como a descrição dos usos externos da língua. Também paralelamente aos formalistas, há funcionalistas que procuram a variação translingüística possível(os universais do uso da língua) e funcionalistas que procuram determinar as causas da variação intra-lingüística. Também procuro mostrar que os funcionalistas podem diferir na extensão do uso de variáveis sociais na explicação da forma lingüística.<br>This article shows that the term "functionalism", very often understood as a single or uniform approach in linguistics, has to be understood in its different perspectives. I start by presenting an opposing conception similar to the I-language vs E-language in Chomsky (1986). As in the latter conception , language can be understood as an abstract model of a mind internal mechanism responsible for language production and perception or, as in the former one, it can be the description of the external use of language. Also like with formalists , there are functionalists who look for cross-linguistic variation (and universals of language use) and functionalists who look for language internal variation. It is also shown that functionalists can differ in the extent to which social variables are considered in the explanation of linguistic form

    Vesicular Stomatitis Virus and RNA Viruses as Gene Therapy Vectors

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