Kazuhiro Yamamoto

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Current status (Thermal noise and sapphire
fibers)
Kazuhiro Yamamoto Institute for Cosmic Ray
Research The university of Tokyo
LCGT cryogenic payload meeting 10 January 2012
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Thermal noise
????? ????????? ??????(1/30)????
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Thermal noise
?????(10Hz??) Pitch ????????30Hz
?????????14Hz (?????????????
???10Hz??) ? ????150Hz ?????????50Hz ????????
?(10Hz??)
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Thermal noise
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Thermal noise
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Thermal noise
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Thermal noise
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Thermal noise
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Thermal noise
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Thermal noise
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Thermal noise
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Thermal noise
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Thermal noise
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Thermal noise
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Thermal noise
?????(10Hz??) Pitch ????????30Hz
?????????14Hz (?????????????
???10Hz??) ? ????150Hz ?????????50Hz ????????
?(10Hz??) ??17Hz?(GAS?)
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Thermal noise
Off resonance???? ??????pitch???30Hz off
resonance pendulum????? yaw???2Hz
off resonance pendulum?2.5??
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Thermal noise
???????pitch???14Hz off resonance
pendulum(?)????? yaw???2Hz off
resonance pendulum(?)?2??
pendulum???1Hz off resonance pendulum(?)?????
????50Hz off resonance
pendulum(?)????? Q????pitch?105?
pendulum?yaw?104?(??????)
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Thermal noise
?????pitch????????(???) yaw???0.2Hz
off resonance pendulum(?)?3??
pendulum???1Hz off resonance pendulum(?)?????
????0.25Hz off
resonance pendulum(?)?????
Q????102?(????) pendulum?yaw?104?(??????)
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Thermal noise
?????????????? ????? pendulum???1Hz off
resonance pendulum(?)????? pendulum Q
104
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Thermal noise
Eddy current damping ???????????????? (pendulum???
???10Hz?pendulum(?)?2??) ???????????? (????)
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Thermal noise
???(1) ?????(10Hz??) Pitch 14Hz(????)?30Hz(?) ?
50Hz(????)?150Hz(?) ?????? ??pitch?pendulum(?)?
???? Q??105????????Q???????
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Thermal noise
???(2) ???? ??pendulum(?)??????Q??102????????????
????pendulum?? Q??104?
Eddy current damping ?????????????????
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Thermal noise
?? ??????????????? ???????????? ????pitch? ???
???????????????????????
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Sapphire fibers
Test sample (T. Uchiyama)
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Sapphire fibers
Three companies Moltech, Kyocera,
Namiki Moltech Uchiyama has already ordered.
They can not polish fibers.
Four fibers has already been made !
Problem Shift (at least 0.1mm)
Kyocera can
polish them. The details should
be discussed.
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Sapphire fibers
Kyocera They can make fiber with thick end but
discussion is in progress.
(Meeting 1st of December) No
fiber will be made (cost). There are
unpolished straight fibers in KEK. If they
are polished, we will check properties.
The fibers has already been sent.
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Sapphire fibers
Namiki They gave up to made and polish fibers
with thick ends. There are unpolished
straight fibers in KEK. If they are
polished, we will check properties. The
fibers has already been sent.
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Bonding
?????????????????
(??) ?????????????(a???) ????????