1. Cryogenic Payload Issues
K. Yamamoto
2015 December 2
4th ELiTES meeting
@Ookayama campus, Tokyo Institute of Technology,
Mugero-ku, Tokyo, Japan 1 1 1 1

2. 0. Abstract Here, I explain Cryostat installation at KAGRA site
Cryogenic payload
Sapphire suspension
Details will be presented by researchers in Japan. 2

3. Cryostat installation Cryogenic payload Sapphire suspension Summary
Contents
Introduction
Cryostat installation
Cryogenic payload
Sapphire suspension
Summary 3

4. 1. Introduction Schematic view of KAGRA interferometer
Four mirrors of arm cavity will be cooled.
3km
3km
Mozumi
Y-end
Sakonishi
X-end
Kamioka mine
(Underground site)
Atotsu
Center
Vibration isolation system (Type A), Cryocooler unit, Cryostat, Cryogenic payload 4 4 4 4 4 4 4 4

5. Vibration isolation system Vacuum ducts along laser beam
1. Introduction
Outline of vibration isolation and cryostat
Design drawing with tunnel and cross section
2nd floor
A. Hagiwara
Vibration isolation system
(room temperature)
14 m
Shaft
Clean booth
Vacuum ducts along laser beam
Cryostat
(Here is a mirror) 5 5 5

6. 1. Introduction Schematic view of cryo-payload Sapphire suspension
Pulse tube cryocoolers
Pulse tube cryocoolers
Sapphire fiber
Cryo-payload
Sapphire mirror (About 20K)

7. 1. Introduction Schematic view of cryo-payload Pulse tube cryocoolers
Cryo duct for 300 K radiation

8. 2. Cryostat installation
Status of one year ago
(T. Suzuki’s talk in last ELiTES meeting)
Two cryostats have already been installed. Leak test and survey were in progress.

9. 2. Cryostat installation
What happened after last ELiTES meeting ?
R. Kumar (T. Suzuki) explains in this session
(tomorrow afternoon).
Last two cryostats were installed.
Cryo ducts are connected to two cryostats in the center room.
Leak test and survey are in progress.

10. 2. Cryostat installation
Geophysics
There is an interferometer for geophysics at KAGRA site.
(Optical components are fixed on ground, not suspended)
Installation was finished and commissioning is started.
K. Miyo presents tomorrow afternoon.
40cm Retro Reflector

11. 2. Cryostat installation
Water is serious problem even now …
But could be an issue in operation ? For example, gravity gradient noise ?
K. Somiya presents tomorrow afternoon.

12. 3. Cryogenic payload Outline of vibration isolation and cryostat
Pulse tube cryocoolers
Pulse tube cryocoolers
Cryo-payload 12 12 12 12 12 12 12

13. 3. Cryogenic payload Outline of cryogenic payload Mirror chain
Platform
Recoil mass chain
Marionette
Intermediate mass
Thermal noise caused by recoil mass chain is small.
Sapphire Mirror 13 13 13 13 13 13 13

14. 3. Cryogenic payload Outline of cryogenic payload GAS filer Platform
for vertical
vibration isolation
(Mirror chain is
suspended)
Platform
Marionette
Intermediate mass
Sapphire Mirror 14 14 14 14 14 14 14

15. 3. Cryogenic payload Outline of cryogenic payload Platform
Alignment adjustment system
Platform
Marionette
Simple system for
high Q-value of sapphire suspension
Intermediate mass
Sapphire Mirror 15 15 15 15 15 15 15

16. 3. Cryogenic payload Outline of cryogenic payload Platform
Sensor and actuator (for control and damping)
Marionette
Intermediate mass
Sapphire Mirror 16 16 16 16 16 16 16

17. 3. Cryogenic payload Design A. Hagiwara proceeds with
Without recoil chain
Design
A. Hagiwara proceeds with
CAD design drawings. Almost
all parts except for platform
were designed.
Design is based
on discussion
with Vibration Isolation
subgroup of KAGRA.
Marionette
Platform
Intermediate mass
Mirror
A. Hagiwara 17 17

18. 3. Cryogenic payload Design A. Hagiwara proceeds with
With recoil chain
Design
A. Hagiwara proceeds with
CAD design drawings. Almost
all parts except for platform
were designed.
Recoil mass for Marionette
Recoil mass for intermediate mass
Recoil mass for mirror
A. Hagiwara 18 18

19. 3. Cryogenic payload Prototype test of cryogenic payload
Two differences from actual one
Platform does NOT include
GAS filter.
Mirror and fibers are NOT made from sapphire, but metal. 19

20. 3. Cryogenic payload Prototype test of cryogenic payload
Without recoil chain
Prototype test of cryogenic payload
Marionette, Intermediate mass,
Dummy mirror, Recoil mass
for dummy mirror has already
been delivered.
Marionette
Intermediate mass
Dummy Mirror (and recoil mass)
A. Hagiwara 20 20

21. 3. Cryogenic payload 23 kg 150 mm 220 mm
Prototype test of cryogenic payload
Dummy mirror and ears (stainless)
Size and weight are the same as those of KAGRA mirror.
23 kg
150 mm
220 mm
Ears (stainless)
Recoil mass 21 21 21 21 21 21 21

22. 3. Cryogenic payload Prototype test of cryogenic payload
(VIC international)
Dummy blade spring
Marionette
Intermediate mass 22 22 22 22 22 22 22

23. 3. Cryogenic payload Prototype test of cryogenic payload
T. Miyamoto assembled !
He is developing
(1) alignment adjustment
system of Marionette
(2) displacement sensor
for control and damping
(3) coil magnet actuator
for sapphire mirror
They should work around 20 K. 23

24. 3. Cryogenic payload Prototype test of cryogenic payload
T. Miyamoto conducts
cooling test on December.
Details of design and
this prototype will
be explained by R. Kumar
in this session. 24

25. 3. Cryogenic payload Schedule Procurement for KAGRA cryogenic payload
First one will be delivered by March 2016.
Other ones will be delivered by March 2017.
ETM and ITM will be delivered by September 2016 and March 2017, respectively.
Installation will be in second half of 2017. 25

26. 4. Sapphire suspension Sapphire lop-eared suspension
“Sapphire monolithic
lop-eared suspension”
One of the most important
parts of KAGRA :
Main sapphire mirrors
are included.
All parts are made
from sapphire.
fiber break
Hydroxide Catalysis Bonding 26

27. 4. Sapphire suspension Blade spring Fiber with nail head on both ends
Sapphire lop-eared suspension
Blade spring
(compensation of fiber length difference)
Fiber with nail head on both ends
Flat cut
Nail head of fiber
Mirror
Ear
A. Hagiwara

28. 4. Sapphire suspension Sapphire lop-eared suspension
When fibers are broken, they can be removed !
Hydroxide Catalysis Bonding

29. 4. Sapphire suspension Sapphire lop-eared suspension
How to make sapphire fiber with nail head ?
(1)Drilling
(2)Bonding
We adopt (2) because the diameter of thin part in (1) is large for KAGRA.
Nail head itself should be small (thermal noise).　　　　　　　　
Drilled
Bonding
Bonding 29

30. 4. Sapphire suspension Current status
We investigated almost all components.
Measurement of Q-values of sapphire fiber
is still in progress.
We are preparing to construct full size suspension
(as prototype).
R. Kumar explains in this session.
Simpler (one fiber) prototype test is in progress.
K. Craig presents in this session. 30

31. 4. Sapphire suspension Full size suspension as prototype
Assembly (thick four fibers, exactly challenge)
Measurement of mechanical response
(resonant frequencies)
Cooling and heat load test
Measurement of Q-values 31

32. 4. Sapphire suspension Full size suspension as prototype
All sapphire parts for full size prototype have already been delivered (IMPEX and Shinkosha).
Sapphire cylinder with flat cuts
as dummy mirror
Fibers with nail head
Blade spring
Ears 32 32 32 32 32 32 32 32

33. 4. Sapphire suspension Full size suspension as prototype
Jigs to assemble full size prototype is being prepared(R. Kumar, K. Craig).
Some parts were delivered. 33 33 33 33 33 33 33 33

34. 4. Sapphire suspension Full size suspension as prototype
Hydroxide Catalysis Bonding
Jig and dummy bulk were prepared (K. Yamamoto). 34 34 34 34 34 34 34 34

35. 4. Sapphire suspension Full size suspension as prototype
Measurement of shape of sapphire bulk and ears
For precise position of ears, the geometrical shape and ears were
measured
(by K. Enami,
Mechanical
Engineering
Center, KEK). 35 35 35

36. 4. Sapphire suspension One fiber prototype
Simpler prototype (easier assembly)
Short cooling time
Sapphire blade spring
Sapphire fiber
145.3mm
6kg sapphire mass
(1/4 of KAGRA mirror)
145.3mm
D. Chen
67.5mm 36 36 36 36 36 36 36 36

37. 4. Sapphire suspension One fiber prototype
Simpler prototype (easier assembly)
Indium bonding, Mechanical response,
Cooling and heat load test,
Thermal cycle test,
Measurement of Q-values,…
H. Tanaka proceeds
with experiment.
K. Craig presents
in this session. 37 37 37 37 37 37 37 37

38. 4. Sapphire suspension One fiber prototype 6kg mass (copper)
(1/4 of KAGRA mirror)
Sapphire blade spring
Nail head of
sapphire fiber
Support frame 38

39. 4. Sapphire suspension One fiber prototype Sapphire blade spring
Dummy Cu wire
Sapphire mass
D. Chen, J. Komma, H. Tanaka, Y. Liu

40. 4. Sapphire suspension Schedule
Procurement for KAGRA sapphire suspension:
Eight fibers and four ears (by March 2016)
Eight fibers and four ears (by March 2017)
ETM and ITM will be delivered by September 2016 and March 2017, respectively.
Installation will be in second half of 2017. 40

41. 4. Sapphire suspension
T. Tomaru and K. Yamamoto joined assembly fused silica suspension of AdVirgo (23rd-27th of November). 41

42. 4. Sapphire suspension
T. Tomaru and K. Yamamoto learned a lot of thing and appreciate their (especially, E. Majorana’s) kindness.
ELiTES stimulates such missions. 42

43. 4. Sapphire suspension Mechanical loss of coating
Thermal noise is dominated by this loss.
Discrepancy between Tokyo and Glasgow
Tokyo
No peak
No annealing effect
Glasgow
Peak around 20 K
Annealing suppresses peak.
I.W. Martin et al.,
Classical and Quantum Gravity
27 (2010)
K. Yamamoto et al.,
Physical Review D 74 (2006) 43 43 43

44. 4. Sapphire suspension Mechanical loss of coating
Measurement at ICRR was repeated with Glasgow group.
Again, no peaks and annealing effect !
E. Hirose et al.,
Physical Review D 90(2014)

45. 4. Sapphire suspension Mechanical loss of coating
LMA provided coating on sapphire disk.
Loss of the same coating was measured by Glasgow and LMA.
First chance of
cross check with
same coating
J. Katayama
presents
this afternoon.
M. Granata et al., Opt. Lett. 38, 5268 (2013)

46. 4. Sapphire suspension
After sucess of reduction of thermal noise, quantum noise must be an issue.
K. Nagano explaines quantum experiment with small mirror tomorrow afternoon.

47. 5. Summary Cryostat installation All four cryostats were installed !
Connection to cryo duct, survey, leak test
are in progress.
Cryogenic payload
Almost all parts except for platform
were designed.
Parts of mirror chain were assembled.
System to adjust or control cryogenic payload
are being developed.
Cooling test will be started soon ! 47

48. 5. Summary Sapphire lop-eared suspension
Assembly jig for full size prototype
are being prepared.
One fiber prototype experiment is in progress.
Measurement of LMA coating mechanical loss
will be started soon. 48

49. Acknowledgement Supported by Mechanical Engineering Center, KEK
Machine shop, The Institute for Solid State Physics,
The University of Tokyo 49 49 49

50. Thank you for your attention !50

51. Backup 51

52. 6. Summary Next step (by Spring 2016)
Full size prototype at KEK and ICRR
2. By Spring 2017
Development of platform (GAS filter)
By Summer 2017
Assembly and test of sapphire suspension
In the second half of 2017
Installation at KAGRA site
One postdoc joins one week later.
KAGRA must take care of KEK people.
Otherwise, they can not work for KAGRA
after 2018. 52

53. 3. Sapphire suspension Schedule By Spring 2016 : Prototype test
of full size sapphire suspension at ICRR
By Autumn 2016 : Procurement
of sapphire parts
By Spring 2017 : Assembly and test
with End sapphire mirrors
By Summer 2017 : Assembly and test
with Front sapphire mirrors
By End 2017 : Installation at KAGRA site 53

54. 3. Cryogenic payload Schedule By Spring 2016 : Prototype test
of full size prototype at KEK
By Spring 2017 : Development of platform
(GAS filter)
By End 2017 : Installation at KAGRA site 54

55. 4. Schedule 55

56. 4. Schedule Full size prototype at KEK and ICRR
Procurement of sapphire parts
Assembly and test
of sapphire part
Development of platform
(GAS filter)
Installation of cryogenic payload 56

57. 4. Schedule Cooling test of cryostat Installation of Type A
Delivery of End sapphire mirrors
Delivery of
Front sapphire mirrors
Installation of cryogenic payload 57 57 57

59. Extremely short commissioning
5. Schedule
Official schedule
iKAGRA observation : By end of 2015
bKAGRA installation and commissioning : By end of 2017
Current budget plan
By March 2016 : One cryogenic payloads
By March 2017 : Three cryogenic payloads (+ spare)
By end of 2017 : Commissioning of bKAGRA
Extremely short commissioning 59

60. 60

61. 3. Cryogenic payload Outline of cryostat Cryogenic payload Mirror
to SAS
Cryogenic payload
Cryostat
Stainless steel t20mm
Diameter 2.6m
Height ~3.6m
M ~ 10 ton
Mirror
View ports
4 Low vibration
cryocooler unit
Cryo-coolers
Pulse tube, 60Hz
0.9 W at 4K (2nd)
36 W at 50K (1st)
Main LASER beam
Remote
valve unit
S. Koike

62. 3. Cryogenic payload Outline of vibration isolation and cryostat
Heat link (pure Al)
Heat link (pure Al)
Pulse tube cryocoolers
Pulse tube cryocoolers
Cryo-payload 62 62 62 62 62 62 62

63. 3. Sapphire suspension Measurement of Q-values of sapphire fiber
Q-value of 350 mm length fiber for KAGRA is not measured yet.
Short (100mm) fiber measurement suggests clamp for fiber brings loss and reduce measured Q-values.
Next talk (H. Tanaka) Probably not necessasry 63