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Kazuhiro Yamamoto

Institute for Cosmic Ray Research (ICRR)the University of Tokyo

KAGRA face to face meeting 　　　University of Toyama, Toyama, Japan

1 August 2014

Cryogenic sub group

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Contribution

R. TakahashiA, H. Tabaka, T. Miyamoto, K. Ono, T. Sekiguchi, Y. Sakakibara, C. Tokoku, M. Kamiizumi, U. Iwasaki, E. Hirose,

A. Khalaidovski, R. Kumar, T. Uchiyama, S. Miyoki, M. Ohashi, K. Kuroda, T. AkutsuA, H. IshizakiA, F. E. Peña ArellanoA, T. SuzukiB, T. TomaruB, N. KimuraB, S. KoikeB, T. KumeB, ToyodaB, MurakamiB, TerashimaB,

HagiwaraB, K. TsubonoC, Y. AsoC, T. UshibaC, K. ShibataC, D. ChenD, N. OhmaeE, K. SomiyaF, R. DeSalvoG, E. MajoranaH, L. NaticchioniH,

W. JohnsonI, A. CummingJ, R. DouglasJ, K. HaughianJ, I. MartinJ, P. MurrayJ, G. HammondJ, S. RowanJ , G. HofmannK,

C. SchwarzK, D. HeinertK, R. NawrodtK, S. GotoL, M. TanakaL, S. IokaM, K. NakamotoM, H. NezukaM, KAGRA collaboration

ICRR.UT, NAOJA, KEKB, Phys.S.UTC, Astro.S.UTD, E.UTE,S.TITF, Sannio Univ.G, INFNH, Louisiana State Univ.I , University of GlasgowJ,

Friedrich-Schiller-Universitaet JenaK, Jecc TorishaL, Toshiba Keihin Product OperationsM, KAGRA collaboration

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0. Abstract

Although there are many topics, here,I will explain recent progress and status of(1)Cryostat(2)Payload(3)Human resources.

Yusuke explains cryo duct after my talk.

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Contents

1.Introduction2.Cryostat3.Payload4.Human resources5.Summary

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1. Introduction

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3km3km

MozumiY-end Sakonishi

X-end

AtotsuCenter

Vibration isolation system, Cryocooler unit, Cryostat, Cryogenic payload

Schematic view of KAGRA interferometerFour mirrors of arm cavity will be cooled.

Kamioka mine (Underground site)

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Outline of vibration isolation and cryostat

14 m

1. Introduction

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Cryogenic mirror

Cryostat

Vibration Isolation

Outline of vibration isolation and cryostat

14 m

1. Introduction

8

to SAS

View ports

Remote valve unit

4 Low vibration cryocooler unit

Main LASER beam

Cryostat Stainless steel t20mm Diameter 2.6m Height ~3.6m M ~ 10 ton

Cryo-coolers Pulse tube, 60Hz 0.9 W at 4K (2nd) 36 W at 50K (1st)

Outline of cryostatCryogenic

payload

Mirror

S. Koike

1. Introduction

99999

2 Pulse tube cryocoolers

2 Pulse tube cryocoolers

Pulse tube cryocoolers

Baffles Cryo duct(Yusuke’s talk)

Outer shield(80K)

Inner shield(8K)

Vacuum chamber

(300K)

1. Introduction

1010101010

Pulse tube cryocoolers

Pulse tube cryocoolers

Pulse tube cryocoolers

Heat link (pure Al)

Sapphire mirror (About 20K)

Heat link (pure Al)

Sapphire fiber

1. Introduction

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One year ago, the cryostats were moved to the warehouse near Kamioka.

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2. Cryostat

1212

First cryostat will be moved to end of Y arm on the 12th-13th of August ! It will be fixed after 19th of Aug.

2. Cryostat

131313131313

Hole on radiation shield for wire from SAS .Duct to reduce radiation invasion is necessary.

1313131313

2. Cryostat

Baffles Cryo duct(Yusuke’s talk)

141414141414

Design is fixed. It is being manufactured in Mechanical Engineering Center of KEK.

2. Cryostat

Ceiling of radiation shield

Duct for SAS

151515151515

Main strategy of cryo payload

One payload in Fiscal year 2014 (by March 2015).

Design drawing

Hagiwara-san (CAD operator in KEK) and Koike-san (Engineer in KEK) proceed (based on Type B payload design).

3. Payload

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Manufacturing factory

We are looking for factories and found three candidates. Mechanical Engineering Center of KEK also can support.

3. Payload

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Sapphire suspension Preparation for (similar size) prototype of lop ear is in progress. We fixed design ear and cut on mirror and ask quotation. Dummy bulk

(Shinkosha)

3. Payload

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Paper about thermal conductivity measurement sapphire fibers with nail heads was accepted !

3. Payload Sapphire suspension

191919191919

Sapphire suspension Bonding technique is necessary.

Two kinds of bonding (Both of them are necessary)

Hydroxide Catalysis Bonding Indium

Thermal resistance and mechanical dissipation must be measured.

3. Payload

202020202020

Sapphire suspensionThermal resistance of bonding (Dan, GWADW2014)

Preliminary

Probably, it is OK, but Dan proceeds ….

3. Payload

212121212121

Sapphire suspensionMechanical loss of indium (Dan in Jena)

3. Payload

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Sapphire suspensionMechanical loss of indium (Dan in Jena)

3. Payload

Investigation is in progress …

232323232323

Sapphire suspension

Dan and Rahul proceeds with calculation of thermal noise using Finite Element Method. The result is coming soon.

3. Payload

242424242424

CuBe blade spring in platform

Intermediate Mass

Intermediate Recoil Mass

Recoil MassTest Mass (sapphire mirror)

Platform includes CuBe spring for vertical vibration isolation.

3. Payload

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CuBe blade spring in platform

Small CuBe sample to check material properties in KEK(1)Q-value(2)Temperature coefficient of Young’s modulus

Fabrication for measurement was finished.We are preparing samples.

3. Payload

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CuBe blade spring in platformLarge CuBe blade spring (provided by VIS group) in 1/4 cryostat in ICRR. They will be moved to KEK on the 8th of Aug.

3. Payload

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Moving mass to adjust angle of platform and intermediate mass

Cryogenic test in KEK will start soon.

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Intermediate Mass

Test Mass (sapphire mirror)

3. Payload

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Fresh persons

Research staff

Tatsuya Kume : Lecturer (KEK) Vibration measurement, Cryo duct

New a few project assistant professors (ICRR) for cryogenic payload, cryogenic mirror and so on They will start to work on the beginning of 2015 in the earliest case.

4. Human resources

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Fresh persons

Graduate students (Master course)

T. Miyamoto, H. Tanaka

Technical staff

Toyoda : Support for cryogenic experiment and Design drawing Terashima : Technician (Machining) Murakami : Technician (Welding) Hagiwara : CAD operator

4. Human resources

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ELiTES: ET-LCGT interferometric Telescope Exchange of Scientists Grant for collaboration about cryogenic between KAGRA and ET European 7th Framework Programme Marie Curie action (Mar. 2012 - Feb. 2016)

European people can visit Japan for KAGRA. In the first half year of 2014, 22 guests came !

4. Human resources

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5. SummaryCryostat First and second cryostats will be installed at Y end of KAGRA site on August , respectively.

Cryo duct Yusuke reports soon !

Payload One payload by March 2015 Design and search for factories are in progress. Prototype of sapphire suspension is being prepared.

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5. SummaryPayload Dan Proceeds with experiment for sapphire boding techniques. KEK proceeds with various tests (CuBe spring, moving mass ....)Fresh persons 1 lecturer, 2 graduate student (master course), 3 technical staffs New project assitant professors come at the January 2015.

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Thank you for your attention !

343434343434

Sapphire suspensionQ of square nail head

353535353535

One fiber prototype

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Some items for future research (not perfect list)

(a)Investigation material properties (Q, thermal conductivity, strength etc.) of coating, fiber and so on.(b)Sapphire bonding, Sapphire fiber clamp(c)Control and damping scheme Actuators and sensors at cryogenic temperature(d) Mechanical and thermal simulation for payload(e) Vertical spring in cryostat(f) Reduction of initial cooling time Thermal resistance of clamp .... (g) Baffles for scattered light in radiation shield(h) Assembly procedure

7. For future

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8. SummaryCryostat : Assembly is in progress. Cooling test is coming soon.Cryogenic duct : Optimum position of 5 buffles Future work : scattered lightCryocooler unit : Cooling test and vibration measurement : OKCryogenic payload Preparation for 1/4 cryostat to check payload performance is in progress. Current main R&D topics Inital cooling time, Sapphire fiber with nail head, Coating mechanical loss, Vibration of shield

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2. Issues

(1)How to assemble Details of construction, clean room ….

(2)Strength Tensile strength, development of clamp, sapphire bonding …

(3)Control and damping system to reduce fluctuation and instability Actuators (what and where), resonant mode (frequency and Q) and so on

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2. Issues

(4)Cooling

Temperature of mirror (below 20 K), initial cooling time, heat resistance of clamp …

(5)Noise

Thermal noise, vibration via vibration isolation system and heat links …

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After Yusuke left …. Clamp for IMPEX fibers in Jena

4. Sapphire fibers

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Profile measurement in Glasgow

4. Sapphire fibers

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Q measurement in Jena

5. Sapphire suspensionSapphire fibers with nail heads

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Outline of vibration isolation and cryostat

4343434343

2 Pulse tube cryocoolers

2 Pulse tube cryocoolers

Pulse tube cryocoolers

Baffles Cryoduct

Outer shield(80K)

Inner shield(8K)

Vacuum chamber

(300K)

444444444444

Sapphire suspensionMechanical loss of indium (Dan in Jena)

Preliminary

Lo

ss a

ng

le

3. Payload

454545454545

Sapphire suspension

Dan’s calculation

Dan and Rahul proceeds with calculation of thermal noise using Finite Element Method. The result is coming soon.

Preliminary

3. Payload