@PhDThesis{ConstâncioJr:2017:CoDeMu,
author = "Const{\^a}ncio Junior, Marcio",
title = "Contribui{\c{c}}{\~o}es ao desenvolvimento do Multi-Nested
Pendula para isolamento vibracional criog{\^e}nico do LIGO
Voyager",
school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
year = "2017",
address = "S{\~a}o Jos{\'e} dos Campos",
month = "2017-05-29",
keywords = "ondas gravitacionais, LIGO, LIGO Voyager, criogenia, Multi-Nested
Pendula, gravitational waves, LIGO, LIGO Voyager, cryogenics,
Multi-Nested Pendula.",
abstract = "Ondas gravitacionais (OG) s{\~a}o perturba{\c{c}}{\~o}es no
espa{\c{c}}o-tempo propagando-se atrav{\'e}s do pr{\'o}prio
espa{\c{c}}o-tempo {\`a} velocidade da luz. Sua
predi{\c{c}}{\~a}o te{\'o}rica deriva da teoria da Relatividade
Geral de Einstein (RG), publicada no in{\'{\i}}cio do
s{\'e}culo XX. Sua exist{\^e}ncia permaneceu apenas na teoria,
embora Hulse e Taylor tivessem apresentado evid{\^e}ncias
indiretas de sua exist{\^e}ncia em 1975, at{\'e} 11 de Fevereiro
de 2016, quando a colabora{\c{c}}{\~a}o cient{\'{\i}}fica LIGO
anunciou a primeira detec{\c{c}}{\~a}o direta de ondas
gravitacionais passando pela Terra. O sinal, detectado em 14 de
Setembro de 2015, era proveniente de um sistema bin{\'a}rio
formado por dois buracos negros em processo de coalesc{\^e}ncia e
deu in{\'{\i}}cio {\`a} era da Astronomia de Ondas
Gravitacionais. O detector interferom{\'e}trico LIGO,
respons{\'a}vel pela detec{\c{c}}{\~a}o, baseia-se no principal
efeito da passagem de uma onda gravitacional, no qual
distor{\c{c}}{\~o}es do espa{\c{c}}o-tempo e em tudo nele
contido podem ser mensurados utilizando-se massas de teste e
monitorando suas dist{\^a}ncias relativas. A varia{\c{c}}{\~a}o
nas dist{\^a}ncias relaciona-se com a amplitude da onda
gravitacional incidente por meio da express{\~a}o h\$\approx\$
\$\frac{\Delta L}{L}\$ . Esse {\'e}, basicamente, o
princ{\'{\i}}pio de funcionamento do interfer{\^o}metro LIGO
que usa espelhos de S{\'{\i}}lica em suspens{\~o}es pendulares
como massa de teste e monitora a dist{\^a}ncia entre eles usando
um feixe laser de alta pot{\^e}ncia. Na {\'e}poca da
detec{\c{c}}{\~a}o, o LIGO estava come{\c{c}}ando sua primeira
corrida cient{\'{\i}}fica da sua segunda gera{\c{c}}{\~a}o,
denominada aLIGO. Contudo, embora a segunda gera{\c{c}}{\~a}o
tenha iniciado as eras de corridas cient{\'{\i}}ficas
recentemente, atualiza{\c{c}}{\~o}es para as
gera{\c{c}}{\~o}es futuras j{\'a} est{\~a}o come{\c{c}}ando a
ser desenvolvidas para serem implantadas em meados da pr{\'o}xima
d{\'e}cada. Uma destas atualiza{\c{c}}{\~o}es, chamada de LIGO
Voyager, prev{\^e} o uso de criogenia para a redu{\c{c}}{\~a}o
de ru{\'{\i}}do t{\'e}rmico das suspens{\~o}es e das massas de
teste. E {\'e} nessa dire{\c{c}}{\~a}o que insere-se a pesquisa
realizada pelo grupo GWINPE (Gravitational Wave Group of Instituto
Nacional de Pesquisas Espaciais), primeiro grupo brasileiro
vinculado {\`a} colabora{\c{c}}{\~a}o LIGO e coautor do artigo
da primeira detec{\c{c}}{\~a}o das ondas gravitacionais. Em
trabalho anterior (mestrado) foi estudado o desenvolvimento de um
sistema multipendular aninhado, chamado de \${''}\$Multi-Nested
Pendula\${''}\$ (MNP), para ser implementado como um
est{\'a}gio adicional ao sistema de isolamento vibracional das
massas de teste de vers{\~o}es futuras do LIGO. Neste trabalho, o
uso deste sistema {\'e} estudado, n{\~a}o s{\'o} visando
constituir um est{\'a}gio de isolamento vibracional adicional
para as massas de teste, mas para incumbir-se da tarefa de manter
as massas de teste do LIGO Voyager resfriadas a 124K enquanto
mant{\'e}m um isolamento vibracional m{\'{\i}}nimo determinado
pela intensidade do retro-espalhamento e recombina{\c{c}}{\~a}o
de f{\'o}tons no feixe principal. Por fim, ser{\'a} apresentada
qual configura{\c{c}}{\~a}o possibilita a manuten{\c{c}}{\~a}o
da temperatura dos espelhos a 124 K sem comprometer aquele
isolamento vibracional m{\'{\i}}nimo e damos
dire{\c{c}}{\~o}es nas pesquisas que precisam ser feitas para
transformar o MNP em um sistema de isolamento vibracional
adicional para o LIGO Voyager e/ou para detectores
interferom{\'e}tricos em geral. ABSTRACT: Gravitational Waves
(GW) are perturbations in space-time, traveling at space-time
itself at the speed of light. Its theoretical prediction derives
from Einsteins General Relativity (GR), published early in the
twentieth century. Their existence remained in theory, although
Hulse and Taylor presented indirect evidences of their existence
in 1975, until February 11th 2016, when the LIGO Scientific
Collaboration (LSC) announced the first direct detection ever made
from gravitational waves passing through the Earth. The GW signal,
detected in September 14th, 2015 came from a binary system formed
by two black holes during their coalescence process and gave rise
to the Gravitational Wave Astronomy era. LIGO interferometric
detector, responsible for this detection, has its working
principle based on the effect of a passing GW, in which
distortions in the fabric of space-time and in everything therein
can be measured by using two test masses and monitoring their
relative distances. The variation in distance can be related to
the amplitude of the incoming GW by h\$\approx\$
\$\frac{\Delta L}{L}\$ . This is, basically, the working
principle from LIGO interferometer, which uses Silica mirrors
hanging from pendular suspensions as test masses and monitors the
distance between them throught a high power laser beam. At the
detection epoch, LIGO was just starting its first scientific run
from its second generation, named aLIGO. However, although the
second generation had just begun its scientific runs era, updates
for the next generations are now starting to be developed in order
to be implemented by the middle of the next decade. One of these
upgrades, named LIGO Voyager, aims to use criogenics in order to
reduce suspension and substrate thermal noise. That\${'}\$s the
direction where the R\\& D developed by GWINPE Gravitational
Wave Group of Instituto Nacional de Pesquisas Espaciais) is
engaged, the first Brazilian group linked to LSC and co-author of
the paper regarding the first direct gravitational-wave detection
ever made. In a previous work (master degree), the development of
a multipendular nested system, named \${''}\$Multi-Nested
Pendula\${''}\$ (MNP), was studied in order to be implemented as
an additional stage to the vibration isolation system of test
masses for future LIGO versions. In this work, we study this
system, not only aiming to be an additional vibration stage for
test masses, but to undertake the task of keeping LIGO Voyager
test masses cooled to 124K while keeps a miminum requirement of
vibration isolation determined by the intensity of photon
backscattering and recombination in the main beam. Finally, well
present which configuration makes possible to maintain the mirror
temperature at 124 K without compromising the minimum vibration
isolation required and we give direction to the researches that
need to be performed in order to convert the MNP into an
additional vibration isolation system for LIGO Voyager and/or
interferometric gravitational wave detectors in general.",
committee = "Jablonski, Francisco Jos{\'e} (Presidente) and Aguiar, Odylio
Denys (Orientador) and Costa, C{\'e}sar Augusto and Ara{\'u}jo,
Jos{\'e} Carlos Neves de and Gratens, Xavier Pierre Marie and
Oliveira Junior, Nei Fernandes de",
englishtitle = "Contributions to the development of the Multi-Nested Pendula for
cryogenic vibration isolation for LIGO Voyager",
language = "pt",
pages = "157",
ibi = "8JMKD3MGP3W34P/3NT7CR2",
url = "http://urlib.net/ibi/8JMKD3MGP3W34P/3NT7CR2",
targetfile = "publicacao.pdf",
urlaccessdate = "27 abr. 2024"
}