Vibration measurement in the cryogenic …...Vibration measurement in the cryogenic interferometric gravitational wave detector (CLIO interferometer) ICRR Univ. of Tokyo, Dept. of

Vibration measurement in the cryogenic interferometric gravitational wave detector (CLIO interferometer)

ICRR Univ. of Tokyo, Dept. of geophysics Kyoto UniversityA,KEKB, Dept. of advanced materials science Univ. of TokyoC,Sumitomo Heavy Industries Ltd.D

K. Yamamoto, T. Uchiyama, S. Miyoki, M. Ohashi, K. Kuroda,H. HayakawaA, T. TomaruB, N. SatoB, T. SuzukiB, T. HaruyamaB,A. YamamotoB, T. ShintomiB, S. MoriwakiC, Y. IkushimaD,T. KoyamaD, R. LiD

2006 March 28 The meeting of Physical Society of Japan @Matsuyama University

0. Abstract

Measurement of the vibration

at the top of suspension and inner shield of CLIO interferometer

Contents

1. Introduction

2. Outline of experiment

3. Results

4. Future works

5. Summary

1. Introduction

LCGT and CLIO : future and current Japanese project

to construct the interferometric gravitational wave detector

(1) Cryogenic interferometer (20 K) : reduction of thermal noise

(2) Kamioka mine : small seismic noise Cryocooler

Vibration

Measurement of vibration with operating cryocooler is necessary.

Schematic view of cryogenic apparatus Vacuum chamber (300 K)

Outer shield (100 K)

Inner shield (8 K)

Mirror (20 K)

Intermediate mass (10 K)

X

Cryocooler (4 K)

(1)Top of suspension (300 K)

(2)Shield (8 K)

Measurement point

(1)Top of suspension (300 K, vacuum) (2)Shield(8K, vacuum)

Heat link

CLIO cryostatin Kamioka mine

Kamioka mine (LCGT,CLIO site)220km west from Tokyo

Tokyo (TAMA)

Kamioka220km

2. Outline of experiment

We are here.

2-1. Location

80K Pulse tubecryocooler

Beam splitter(100m ahead)

Gifford-McMahon refrigerator(removal)

by T. Uchiyama

ShieldCompressor

Mirror

Top of suspension(room temperature, vacuum, 1.9 m from floor, support of four poles)

4K Pulse tubecryocooler

Pulse tube cryocooler : extremely small vibration(developed by KEK and Sumitomo Heavy Industries Ltd.)Class. Quantum Grav. 21(2004)S1005.

2-2. Cryostat of CLIO interferometer (end)

Inner shield(low temperature, vacuum, 0.6 m from floor, support of G10 rods)

Cryostat of CLIO interferometer

Top roof

Door

Top of suspension

Cryostat of CLIO interferometer

Top roof

Door

Inner shield

Bottom of shield

Duct

BeamSplitter(fixed)

Lasersource(diode)

PhotoDetector

Differential amp Filter

ReferenceMirror(fixed)

Steeringmirror

+

Vacuum chamber

Output

Oscillator

2-3. Accelerometer

5 mW

635 nm

(Laser source and photo detectors are in vacuum chamber. Sound does not affect accelerometer directly.)

PhotoDetector

Only room temperature

Observation band

< 400 Hz (horizontal)< 250 Hz (vertical)

Accelerometer

Laser source

Photo detectors

Coil

BeamSplitter

Oscillator

Referencemirror

145 mm

10-14

10-13

10-12

10-11

10-10

10-9

10-8

10-7

10-6

10-5

Dis

plac

emen

t [m

/Hz1/

2 ]

0.1 1 10 100 1000

Frequency [Hz]

10 / [m/Hz ]

-9 2f1/2

Top of suspension(Horizontal) Pulse,pump on

(2005/3/10:first) Pump on

(2005/3/10:second) Off

(2005/2/3:second) Kashiwa

(2004/8/6:second)

3. Results

(Horizontal:optical axis)

< 200 HzCryocoolers and pump

not increasedovibration.

Vertical : similar

3-1. Top of suspension

> 200 HzCryocoolers and pump

increase vibration.

10-14

10-13

10-12

10-11

10-10

10-9

10-8

10-7

10-6

10-5

Dis

plac

emen

t [m

/Hz1/

2 ]

0.1 1 10 100 1000

Frequency [Hz]

10 / [m/Hz ]

-9 2f1/2

Shield (Horizontal) Pulse on

(2005/10/6) Pump on

(2005/10/5) Off

(2005/10/4) Kashiwa

(2004/8/6:second)

(Horizontal:optical axis)

Cryocoolers and pumpsnot increasedo

vibration.

3-2. Inner shield

G10 rods > 200 Hz

vibration isolation

10-14

10-13

10-12

10-11

10-10

10-9

10-8

10-7

10-6

10-5

Dis

plac

emen

t [m

/Hz1/

2 ]

0.1 1 10 100 1000

Frequency [Hz]

10 / [m/Hz ]-9 2f 1/2

Shield (Vertical) Pulse on

(2005/10/13:second) Pump on

(2005/10/13:first) Off

(2005/10/12) Kashiwa

(2004/8/16:first)

Cryocoolers : peaks

3-3. Inner shield (Vertical)

G10 rods

Vacuum pumpsincrease vibration.

> 200 Hz

vibration isolation

10-14

10-13

10-12

10-11

10-10

10-9

10-8

10-7

10-6

10-5

Dis

plac

emen

t [m

/Hz1/

2 ]

0.1 1 10 100 1000

Frequency [Hz]

10 / [m/Hz ]

-9 2f1/2

Horizontal motion Top of suspension

(2005/2/3:second) Inner shield

(2005/10/4:first) Floor (RION)

(Perpendicular end 2005/5/10)

Kashiwa (2004/8/6:second)

(Horizontal:Optical axis)

: 30 Hz

3-4. Comparison with floor

Suspension toppeak

Inner shield

Floor 10 / f [m/Hz ]-9 2 1/2

10 Hz - 200 Hz100 times

10-14

10-13

10-12

10-11

10-10

10-9

10-8

10-7

10-6

10-5

Dis

plac

emen

t [m

/Hz1/

2 ]

0.1 1 10 100 1000

Frequency [Hz]

10 / [m/Hz ]

-9 2f1/2

Vertical motion Top of suspension

(2005/6/8:first) Inner shield

(2005/10/12:first) Floor (RION)

(Inline end 2005/5/11)

Kashiwa (2004/8/16:first)

(Vertical)

: 30 Hz, 40 Hz

3-5. Comparison with floor

Suspension top

peak

Inner shield

Floor10 / f [m/Hz ]-9 2 1/2

10 Hz - 200 Hz10 times

10-21

10-20

10-19

10-18

10-17

10-16

10-15

10-14

10-13

10-12

10-11

10-10

10-9

10-8

10-7

Dis

plac

emen

t [m

/Hz1/

2 ]

100 101 102 103 104

Frequency [Hz]

by T. Uchiyama

Noise budget of CLIO From top of suspension From inner shield Shot noise Radiation pressure noise Standard quantum limit Thermal noise (mirror) Thermal noise (mirror at 300K)

3-6. Sensitivity of CLIO

External vibration doesnot limit sensitivityabove 40 Hz at 300 K.

< 40 Hz

Suspension topdominant

interferometer

above 60 Hz at 20 K.

4. Future works (For LCGT)

(1) Cryocooler : no serious problem

(2) Vacuum pump : some problems (inner shield, vertical motion)

(Dry pump) < (Rotary and turbo pump)

Connection with cryostat

(3) Suspension top : peak (30 Hz)

SAS

(4) Inner shield : large vibration (10 Hz - 200 Hz)

SPI

Study of inner shield vibration

5. Summary

(1) Measurement of the vibration at top of suspension and

inner shield of CLIO interferometer

(2) Cryocooler : no serious problem

Vacuum pump : some problems (inner shield, vertical motion)

(3) Suspension top : peak (30 Hz)

Inner shield : large vibration (10 Hz - 200 Hz : 10 - 100 times)

(4) CLIO interferometer sensitivity :

External vibration does not limit sensitivity above 40 Hz at 300 K.

above 60 Hz at 20 K.

(5) Future works for LCGT : Vacuum pump

Inner shield vibration

Super KAMIOKANDEKamLAND

(LISM[20m])

CLIO[100m]

CLIO Location in Kamioka mine

Dark Matter Detector

Location of experimentSuperconductinggravimeter

(KAMIOKANDE)

Exit

Inline

Perpendicular

Dry pump

Dry pump

Turbo pump

Duct of CLIOinterferometer Cryostat

To rotary pump

4K Pulse tube refrigerator

80K Pulse tube refrigerator

Compressor

Gifford-McMahonrefrigerator

thermal switch

低振動冷凍機システムの構成

床／岩盤床／岩盤

バルブ台バルブ台

コンプレッサーコンプレッサー

ベローズベローズ 高純度金属撚線高純度金属撚線

x

g支持枠支支

持持枠枠

^

e

真空容器真真

空空容容器器

FRP Rod Rod

冷却部80K

冷却部4K

Cryostatとととと接接接接続続続続

SHI SRP-052A 段パルス管冷凍機2

2. Outline of Experiment2-1. Outline of accelerometer

Free mass

Sensor

Actuator

Force

Acceleration

(i) Free mass : reference

(ii) Sensor : displacement between free mass and shield

(iii) Actuator : feedback

Mass follows shield.

Shield

Acceleration of shield is derived from feedback signal.

Horizontal and vertical vibration measurementGoal sensitivity : Seismic motion in Kamioka mine

2-2. Components of accelerometer

(iii) Actuator : Coil-magnet actuator (Operation at low temperature)

(i) Free mass : Mechanical harmonic oscillator

20 mm length0.3 mm thickness1 mm width

Material : Phosphor bronze

Resonant frequency : 20 Hz

20 mm * 20 mm *20 mm

(ii) Sensor : Michelson interferometer (Calibration)

Vertical oscillator

Referencemirror

BS

Oscillator

Coil

Steeringmirrorholder

Accelerometer

Interferometer

Lasersource

Beam splitter of CLIO

Top of suspension

10-15

10-14

10-13

10-12

10-11

10-10

10-9

10-8

10-7

10-6

10-5

Dis

plac

emen

t [m

/Hz1/

2 ]

10-1 100 101 102 103 104 105

Frequency [Hz]

Interferometer noise Horizontal, Top of suspensionpulse, pump off

interferometer noise(2005/3/16:third)

seismic motion(2005/2/3:second)

10-15

10-14

10-13

10-12

10-11

10-10

10-9

10-8

10-7

10-6

10-5

Dis

plac

emen

t [m

/Hz1/

2 ]

10-1 100 101 102 103 104 105

Frequency [Hz]

Interferometer noise Top of suspensionVertical, off

interferometer noise (2005/7/7:second)

seismic motion (off:2005/6/8:first)

10-15

10-14

10-13

10-12

10-11

10-10

10-9

Dis

plac

emen

t [m

/Hz1/

2 ]

10-1 100 101 102 103 104 105

Frequency [Hz]

Noise of interferometer (off)Top of suspension

vertical(2005/7/7:second) horizontal(2005/3/16:third)

10-15

10-14

10-13

10-12

10-11

10-10

10-9

Dis

plac

emen

t [m

/Hz1/

2 ]

1022 4 6 8

1032 4 6 8

1042 4 6 8

105

Frequency [Hz]

Top of suspensionHorizontal

pulse,pump on (2005/3/10:first)

pump on (2005/3/10:second)

pulse,pump off (2005/2/3:second)

10-15

10-14

10-13

10-12

10-11

10-10

10-9

Dis

plac

emen

t [m

/Hz1/

2 ]

1022 4 6 8

1032 4 6 8

1042 4 6 8

105

Frequency [Hz]

Suspension top (Vertical) Pulse on

(2005/6/14:second) Pump on

(2005/6/8:third) Off

(2005/6/8:first)

10-15

10-14

10-13

10-12

10-11

10-10

10-9

Seis

mic

mot

ion

[m/H

z1/2 ]

1022 4 6 8

1032 4 6 8

1042 4 6 8

105

Frequency [Hz]

Top of suspensionHorizontal motion

pulse,pump on (2005/3/10:first)

pulse,pump off (2005/2/3:second)

fixed mirror (on) (2005/3/16:first)

fixed mirror (off) (2005/3/16:third)

3-2. Horizontal motion(optical axis:>100Hz)

>400HzUpper limit

Refrigerator increases vibration100 times (1 kHz).

10-15

10-14

10-13

10-12

10-11

10-10

10-9

Dis

plac

emen

t [m

/Hz1/

2 ]

1022 4 6 8

1032 4 6 8

1042 4 6 8

105

Frequency [Hz]

Suspension top (Vertical) Pulse on

(2005/6/14:second) Off

(2005/6/8:first) fixed mirror(Pulse on)

(2005/7/8:first) fixed mirror(Off)

(2005/7/7:second)

10-15

10-14

10-13

10-12

10-11

10-10

10-9

10-8

10-7

10-6

10-5

Dis

plac

emen

t [m

/Hz1/

2 ]

10-1 100 101 102 103 104 105

Frequency [Hz]

10 / [m/Hz ]

-9 2f1/2

Vertical motion pulse on

(2005/6/14:second) pulse,pump off

(2005/6/8:first) pump on

(2005/6/8:third) Kashiwa

(2004/8/16:first)

3-2. Vertical motion(< 1 kHz)

floor level (1 Hz-70 Hz)

10 / f [m/Hz ]-9 2 1/2

< 200 HzCryocoolers

not increasedovibration seriously.

10-14

10-13

10-12

10-11

10-10

10-9

10-8

10-7

10-6

10-5

10-4

Seis

mic

mot

ion

[m/H

z1/2 ]

0.1 1 10 100 1000

Frequency [Hz]

10 /f[m/Hz ]

-9 2

1/2

Vertical motion pulse,pump on

(2005/3/18:second) pulse,pump off

(2005/3/18:first) CLIK end

(2004/8/16:first)

3-3. Vertical motion(< 1 kHz)

10 /f [m/Hz ]-9 2 1/2

floor level (1 Hz-100 Hz)

Refrigeratordoes not increase

< 200 Hz

vibration seriously.

Cryostat

RION

10-13

10-12

10-11

10-10

10-9

10-8

10-7

10-6

10-5

10-4

10-3

Seis

mic

mot

ion

[m/H

z1/2 ]

0.1 1 10 100 1000

Frequency [Hz]

GM refrigerator (Horizontal motion)

GM on (2005/1/21:second)

pulse,pump on (2005/3/10:first)

CLIK end (2004/8/6:second)

3-5.Gifford-McMahon refrigerator(Horizontal motion)

GM refrigeratorinceases vibration.

30 Hz-400 HzKashiwa level !

10-13

10-12

10-11

10-10

10-9

10-8

10-7

10-6

10-5

Seis

mic

mot

ion

[m/H

z1/2 ]

0.1 1 10 100 1000

Frequency [Hz]

Seismic motion CLIK (Kashiwa) end

pump off (2004/3/13) optical table (2004/2/21)

3-2. Operation at room temperature (2)

- 30 Hz : about

30 Hz -100 Hz :

same

larger motion

100 Hz - : in cryostat

better sound isolationin cryostat

(Cryostat vs optical table)

10-13

10-12

10-11

10-10

10-9

10-8

10-7

10-6

10-5

Seis

mic

mot

ion

[m/H

z1/2 ]

0.1 1 10 100 1000

Frequency [Hz]

Consistent(0.2 Hz - 100 Hz)

Horizontal seismic motion in cryostat (2004/8/5:in air:Kashiwa)

Interferometer RION

3. Results3-1. Operation at room temperature3-1-1. Comparison with RION

(i) Horizontal motion

10-13

10-12

10-11

10-10

10-9

10-8

10-7

10-6

10-5

Seis

mic

mot

ion

[m/H

z1/2 ]

0.1 1 10 100 1000

Frequency [Hz]

Consistent(0.3 Hz - 100 Hz)

Vertical seismic motion in cryostat (2004/8/14:in air:Kashiwa)

Interferometer RION

(ii) Vertical motion

10-15

10-14

10-13

10-12

10-11

10-10

10-9

10-8

10-7

10-6

10-5

Dis

plac

emen

t [m

/Hz1/

2 ]

0.1 1 10 100 1000

Frequency [Hz]

Shield of CLIO cryostatHorizontal,perpendicular endpump,PT off

Interferometer (2005/11/30)

RION(2005/11/30)

10-12

10-11

10-10

10-9

10-8

10-7

10-6

10-5

10-4

Dis

plac

emen

t [m

/Hz1/

2 ]

0.12 4 6 8

12 4 6 8

102 4 6 8

100Frequency [Hz]

Shield of CLIO cryostat 2005/10/4(pump,PT off) 2005/10/4(50m pump on)

Duct

Rotary pumpTurbo pump

50 m pump