1. Status of the Large-scale Cryogenic Gravitational Wave Telescope Project KAGRA
Kazuhiro Yamamoto
on behalf of KAGRA collaboration
Department of Physics, University of Toyama
2017 September 13
The meeting of Physical Society of Japan
@Mine campus, Utsunomiya University, Utsunomiya, Tochigi 1 1 1 1

2. Gravitational wave
1916 : A. Einstein predicted gravitational wave (General relativity)
A. Einstein(Wikipedia)
2015 : LIGO detected gravitational wave directly.
LIGO open science center 2 2 2 2 2 2 2 2

3. In last two years What happened so far ? Observation period
O1 : 2015 Sep Jan 19
O2 : 2016 Nov Aug 25
Three events (binary black hole coalescences)
Physical Review Letters 116(2016)
Physical Review Letters 116(2016) Physical Review Letters 118(2017)
Virgo joins O2 (2017 Aug )
LIGO and Virgo have one year break for improving. 3 3 3 3 3 3 3 3

4. After O2 LIGO Scientific Collaboration News
25 August The Virgo and LIGO Scientific Collaborations have been observing since November 30, 2016 in the second Advanced Detector Observing Run ‘O2’ , searching for gravitational-wave signals, first with the two LIGO detectors, then with both LIGO and Virgo instruments operating together since August 1, Some promising gravitational-wave candidates have been identified in data from both LIGO and Virgo during our preliminary analysis, and we have shared what we currently know with astronomical observing partners. We are working hard to assure that the candidates are valid gravitational-wave events, and it will require time to establish the level of confidence needed to bring any results to the scientific community and the greater public. We will let you know as soon we have information ready to share. 4 4 4 4 4 4 4 4

5. Next step
(1)Better sensitivity : Plans for 3rd generation (10 times better sensitivity than current 2nd generation)
(2)Many other detectors for finer direction resolution
KAGRA : 2nd generation detector in Japan
(Kamioka)
Unique key features :
Underground site with small seismic motion
Cooled mirror and its suspension
to reduce thermal noise
-> 3rd generation adopts these idea. 5 5 5 5 5 5 5 5

6. KAGRA timeline
Phase 2
Phase 1
300K 6 6 6 6 6 6 6 6

7. BNS inspiral range [Mpc]
感度の進展予想
Y. Michimura
13aS35 2
KAGRAはどのように感度を上げていくか？
LIGO Voyager(米)
1000
どのように世界一を目指すか？
どのようにいち早く
重力波観測に加わるか？
upgrade
KAGRA+?
design
AdV+? O3
design
BNS inspiral range [Mpc]
aLIGO(米) O2
design
100 O1 O3
AdV(欧) O2
KAGRA(日)
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026 7
year
Based on Living Reviews in Relativity 19, 1 (2016) 7 7 7 7 7 7 7 7

8. Vibration isolation and cryostat Vacuum ducts along laser beam
Design drawing with tunnel and cross section
2nd floor
A. Hagiwara
14 m
Shaft
Clean booth
Vacuum ducts along laser beam
Cryostat 8 8 8

9. Vibration isolation and cryostat
A. Hagiwara
Vibration isolation system
(room temperature)
Cryogenic payload
(Mirror is on bottom side of payload) 9 9 9

10. Vibration isolation and cryostat
Finally, we installed this vibration isolation and cryogenic payload
(almost same as practical one) at one end station.
A. Hagiwara
Vibration isolation system
(room temperature)
Cryogenic payload
(Mirror is on bottom side of payload) 10 10 10

11. Vibration isolation and cryostat
Cryogenic payload
Mirror and payload was cooled down (12K, initial cooling time is 23 days).
A part
of vibration isolation 11 11 11

12. Cryogenic payload Vibration measurement T. Ochi 13pU34 2
Performance test
T. Miyamoto
13pU34 4
Heat link
T. Yamada
13pU34 3
Mirror 12 12 12

13. Sapphire mirror Absorption in mirror M. Manuel
14aU11 11
Mirror contamination (residual gas)
K. Hasegawa 13pU34 5
Ears bonding
to suspend
mirror
T. Ushiba
13pU34 1 13 13 13

14. Vibration isolation R. Takahashi 13aS35 3 A. Shoda 13aS35 5 M. Barton
161207_SAITO
BRT
Type-A system
ETM
bKAGRA phase-I (- Mar 2018)
- Cryogenic test mass
Sapphire, 23kg, 20K
- Tall seismic isolator
IP + GASF + Payload
Y-arm
R. Takahashi
13aS35 3
ITM MC
PRM BS
X-arm
Type-C system
BRT IO
- Mode cleaner
Silica, 0.5kg, 290K
- Stack + Payload
ITM
ETM
Type-Bp payload
Test mass and Core optics (BS, FM,..)
Silica, 10kg, 290K
- Seismic isolator
Table + GASF + Type-B Payload
A. Shoda
13aS35 5
Type-B system
SRM
- Core optics (BS, SRM,…)
Silica, 10kg, 290K
- IP + GASF + Payload
- Stack for aux. optics
OMMT
OMC
M. Barton
13aS35 4 14 14 14

15. Current status of VIS Type-A
Y-End: Installed. Cooling test of the cryogenic payload is on going.
X-End: Installation work is on going. Setting the Filter1 stage now.
Type-B
BS test hanging was finished.
Real BS installation is on going.
Type-Bp
PR2 & PR3 have been installed.
PRM installation is on going.
Bottom filter and dummy payload
in Y-end.
BS payload with assembly frame.
Installation of PR2. 15 15 15

16. Vibration isolation and ground motion
Crackling noise
in vibration isolation system
M. Kirii
13pU34 12
We try to measure Crackling noise on KAGRA suspension. ・We assembled new measuring system in KAGRA mine. ・We found that the noise is reduced in the low frequency range compared to the measurement in Kashiwa.
Compensation of slow motion of ground
K. Miyo
13aS35 6 16 16 16

17. Component of interferometer
161207_SAITO IO MC
ETM
ITM
Y-arm
X-arm BS
SRM
PRM
BRT
OMC
OMMT
Transmission monitor system
T. Akutsu on behalf of
T. Morozumi
13aS35 7
Intensity stabilization
Green lock
University of Toyama
BRT
Output mode cleaner
J. Kasuya
13aS35 8

18. Intensity stabilization
Achieved noise reduction
30Hz
100Hz
University of Toyama

19. Intensity stabilization
University of Toyama

20. Green lock University of Toyama PD 40Mhz EOM Optical fiber SHG AOM
PDH PD
40Mhz
EOM
Optical fiber
PLL
SHG
AOM
Laser 2 PD
PR2 BS
X-Armcavity
Laser 1
PR3
University of Toyama

21. Experiment of PLL system
Green lock
Experiment of PLL system
University of Toyama
Beatnote
Frequency divider
Beatnote is locked at 129MHz

22. Component of interferometer
161207_SAITO IO MC
ETM
ITM
Y-arm
X-arm BS
SRM
PRM
BRT
OMC
OMMT
Transmission monitor system
T. Akutsu on behalf of
T. Morozumi
13aS35 7
Intensity stabilization
Green lock
University of Toyama
BRT
Output mode cleaner
J. Kasuya
13aS35 8

23. Transmission monitor system T. Akutsu on behalf of
T. Morozumi
13aS35 7

24. Component of interferometer
161207_SAITO IO MC
ETM
ITM
Y-arm
X-arm BS
SRM
PRM
BRT
OMC
OMMT
Transmission monitor system
T. Akutsu on behalf of
T. Morozumi
13aS35 7
Intensity stabilization
Green lock
University of Toyama
BRT
Output mode cleaner
J. Kasuya
13aS35 8

25. アウトプットモードクリーナ Output mode cleaner J. Kasuya 13aS35 8
講演タイトル：KAGRA用アウトプットモードクリーナの開発V (東工大 粕谷)
出射光学系のレイアウトを決定
OMC防振装置の要求値を計算
OMC用の板バネを開発
Output mode cleaner
J. Kasuya
13aS35 8

26. Calibration Calibration is always crucial point in experiments !
Calibration of gravitational wave detector : < 1%
Photo calibrator shakes mirror for calibration.
(Back action (momentum) of reflected light).
Overview
Y. Inoue
13aS35 11 26 26 26

27. Power modulation Camera (beam spot) Bin-Hua. Hsieh. T. Shishido
13aS35 12
Camera (beam spot)
T. Shishido
13aS35 13 27 27 27

28. Calibration How to calibrate with calibrator ? Signal injection test
T. Yokozawa
13aS35 11
Calibration in iKAGRA
T. Yamamoto
13aS35 10 28 28 28

29. Data transfer

30. 99.99 % のファイルを 1 s 以内に大阪市立大学へ転送可能
Data transfer
転送システム性能評価(2)：結果
坑内から大阪市立大学への転送遅延の累積相対度数分布
99.99 % のファイルを 1 s 以内に大阪市立大学へ転送可能
K. Sakai
13pU34 6

31. Data analysis Test run Data analysis is in progress. 300K 31 31 31 31

32. Binary coalescence search and correlation analysis
H. Yuzurihara
15aU31 1
M. Sasai
15aU31 2
Noise characterization

33. Summary Gravitational wave was detected.
We need more detectors for astronomy : KAGRA
bKAGRA phase 1 : by March 2018
Cryogenic Michelson interferometer operation
We strongly proceed with preparation, installation, development, and investigation.
Details of KAGRA are presented today.
Some talks will be tomorrow or the day after tomorrow. 33

34. Thank you for your attention !34