Cryopayload's Action Item List

A/I#

Identified on

Assigned to

Status/Output

Related to

Description

Due date

001

2013 Nov. 19

Sekiguchi, Hirose

Closed. Takanori and Osamu Miyakawa found the document about OSEM (it includes the schematic design of circuit) by themselves.

Control

Ask somebody in LIGO details of the circuit for OSEM.

2013 Nov. 26

002

2013 Nov. 19

R. Takahashi

Closed. Unfortunately, there is not 3 dimensional but only 2 dimensional design drawing.->#016

Overall design

3-D design drawing of Type-A is necessary (ASAP!). Ask to Gianni.

2013 Nov. 26

003

2013 Nov. 19

R. Takahashi

Closed. Ryutaro explained. However, further discussion is necessary.->(#011)

Vertical spring

About blade metal spring (vertical spring), the schedule and strategy and so on will be summarized by R. Takahashi, Ishizaki, Sekiguchi, and K. Yamamoto, and reported in the next meeting.

2013 Nov. 26

004

2013 Nov. 19

K. Yamamoto

Closed. (1)Eric is busy. Moreover, Eric does not use ANSYS or COMSOL. However, Yoichi (or his student) will calculate it using COMSOL (Kazuhiro wrote Yoichi on Microsoft Project).(2)No files remain in Ando lab.

Material

About the masses, including a recoil mass, intermediate mass, intermediate recoil mass, and platform, the evaluation of the eddy current damping is necessary. K. Yamamoto will ask (1) to Eric Hennes how much he can make his effort for this problem and whether he can provide files for Finite Element Analysis. (2) to Ando or Aso whether Nishi's file for eddy current damping still remains.

2013 Nov. 26

005

2013 Nov. 19

D. Chen

Closed. The Picomotor didn’t work at 77K. But that might be because of the cooling shock. So we will have quick cooling test.

Control

D. Chen will ask Uchiyama whether a picomotor can survive at cryogenic temperature.

2013 Nov. 26

006

2013 Nov. 19

D. Chen

Closed. He received the design drawing from Takanori.

Control

D. Chen looks for design drawing of a stage for Type-B, and some commercial stages.

2013 Nov. 26

007

2013 Nov. 19

K. Yamamoto

Closed. Kazuhiro rewrote it.

Control

The schedule for the control system should be considered again.

2013 Nov. 26

008

2013 Nov. 19

K. Yamamoto

Closed. Dan asked Ryutaro.

Control

About the procurement of the OSEMs, K. Yamamoto will consult R. Takahashi.

2013 Nov. 26

009

2013 Nov. 19

T. Suzuki

Urgent! Saito-san introduced ceramic bearing (and companies, NTN, NSKN). Takayuki Tomaru showed other one (http://www.jaxa.jp/press/nal/20020327_bearing_j.html) (#043)

Control

Check whether the thrust bearing can work at the cryogenic temperature. This part is necessary to adjust angle between intermediate mass and its recoil mass. But, it works for initial alignment. Thrust bearing is about 50mm in diameter and load is about 100kg.

2013 Nov. 26

010

2013 Nov. 19

D. Chen (?)

Closed. (i)In order to fix LED and PD, circuit board is used. We must check circuit board is OK at low temperature. -> #019(ii)Dan shows 7m cable increases the noise. Long cable can generates oscillation at high frequency region. The length of cables for cryo payload is 20m in length. We must check how much the long (flat) cable generates noise. If it is a problem, satellite boxes in vacuum are necessary. (iii)Window of photo detector will be removed because nitrogen gas is in Photo Diode.

Control

About OSEM, (i)check about out gas; (ii)check noises by 10-m long line; (iii)check whether the window of photodiode be removed.

2013 Nov. 26

011

2013 Nov. 26

T. Sekiguchi

Closed. Takanori summarized and explained.Vibration via heat link (T. Sekiguchi)->#017

Vertical spring

For the basis of discussion, Takanori will summarize the vibration via heat link until this weekend. After that, he and Ryutaro circulate their ideas about vertical spring and we discuss.

2013 Dec. 1

012

2013 Nov. 26

K. Yamamoto

Urgent! He rewrote, but again, he must do so. First of all, strategy must be fixed.

Vertical spring

Kazuhiro rewrites schedule.

2013 Dec. 3

013

2013 Nov. 26

K. Yamamoto

Closed. He explained. Strategies for sapphire monolithic suspension 2(K. Yamamoto)He also revised schedule.

Sapphire monolithic suspension

Kazuhiro will summarize the details of schedule for monolithic sapphire suspension based on above discussion by the next meeting.

2013 Dec. 3

014

2013 Nov. 26

T. Suzuki and K. Yamamoto

Closed. Now, members of SEO and EO recognized the issue, but how to fix ?

Sapphire monolithic suspension

Suzuki-san and Kazuhiro will report the serious lack of human resources on the next year to SEO and EO.

2013 Dec. 3

015

2013 Nov. 26

R. Kumar

Closed. Rahul investigated and explained Sapphire blade spring. Kazuhiro (Hayama) (and Kentaro and Yoichi) gave comments about data analysis (and noise and control).

Sapphire monolithic suspension

Rahul investigates how much the lowest frequency of sapphire spring is. After that, we ask it is a problem for observation to Data Analysis group.

2013 Dec. 10

016

2013 Dec. 3

R. Takahashi, E. Hirose

Closed. Takanori and Eiichi summarized Preliminary design of Type-A suspension system. Rahul’s new mission ->(#048).

Overall design

Type A 3 dimension drawing. Ryutaro gives Eiichi 2 dimensional design drawing and Eiichi makes drawings.

017

2013 Dec. 3

R. Takahashi, H. Ishizaki, T. Sekiguchi

Finally, this was ordered. The delivery date is 20th of January in the earliest case.

Vertical spring

Design drawing for vertical spring in platform (Ishizaki and Takahashi). Takanori takes care of shape of blade spring. The load on GAS in Type B like is different from that of Ad LIGO like.

018

2013 Dec. 3

K. Yamamoto

Closed. He summarized (in Japanese. Cryogenic payload strategy).

Material

Kazuhiro summarize requirement of magnetization and so on before the meeting with Sumikin

2013 Dec. 17

019

2013 Dec. 3

R. Takahashi

Urgent!

Control

Ryutaro will consult Saito-san on the outgas of circuit board for OSEM.

020

2013 Dec. 3

K. Yamamoto

Urgent!

Sapphire monolithic suspension

Kazuhiro summarize the length of sapphire fiber. He must take bending point and adjustment of diameter into account

17 Dec 2013

021

2013 Dec. 3

K. Yamamoto

Urgent! He summarized in Japanese (13 and 14 pages of payload strategy(in Japanese). He will summarize in English.

Sapphire monolithic suspension

Kazuhiro write the report about backup plan.

17 Dec 2013

022

2013 Dec. 3

D. Chen

Closed. -> (#040)

Sapphire monolithic suspension

He considers structure in the intermediate mass (sapphire blades, stepping motor, stages). Later we discuss.

17 Dec 2013

023

2013 Dec. 10

T. Akutsu

Overall design

Baffle design : Mirror can observe the frame of hole of radiation shield for laser beam. It is an issue of scattered light. We also consider how to reduce the size of baffle.

024

2013 Dec. 10

Y. Aso, E. Hirose

Urgent! Kazuhiro summarizes points and consults with them.

Sapphire monolithic suspension

Yoichi Aso and Eiichi Hirose prepare the plan and R&D items of optical contact and screw, respectively.

24 Dec 2013

025

2013 Dec. 10

E. Hirose

Urgent! Kazuhiro summarizes points and consults with him.

Sapphire monolithic suspension

Eiichi prepares document describing planned test and contributions.

24 Dec 2013

026

2013 Dec. 10

D. Chen

Closed. He asked and we discussed this topic.->(#041,042)

Sapphire monolithic suspension

Dan will ask Ryutaro what is pro and con of large intermediate mass.

17 Dec 2013

027

2013 Dec. 10

T. Suzuki

Closed. He released Sapphire surface friction.

Sapphire monolithic suspension

Suzuki-san has data of friction between sapphire and sapphire and he will circulate later.

17 Dec 2013

028

2013 Dec. 10

Y. Aso

Urgent!

Vertical spring

Yoichi checks vibration transfer function of heat links with extra pendulums and whether weight of mass of these pendulums can be on the order of kg using ANSYS or COMSOL.

029

2013 Dec. 10

T. Suzuki, S. Koike, C. Tokoku

Closed. Koike-san prepared Drawing payload and baffle in shield.

Overall design

Suzuki-san asks Koike-san to provide design drawing in shield. Tokoku-san learns how to handle it in CAD.

030

2013 Dec. 10

T. Suzuki, N. Kimura

In this time, we do not order. Kimura-san expects that small bunch can be ordered. Anyway, we obtained small test pieces.

Material

Suzuki-san (or Kimura-san) checks the schedule of procurement of NSSC130S.

17 Dec. 2013

031

2013 Dec. 10

Y. Sakakibara

Urgent!Yusuke will order four samples. Two of them are with ECB and the other ones are without ECB. But quality of ECB is not guaranteed.

Material

Yusuke orders sphere made from SUS 316L and 305M to check how machining is difficult and whether deposition of SolBlack is OK.

032

2013 Dec. 10

C. Tokoku

Closed. She found that Cryogenic Research Center in Hongo campus has SQUID. She is preparing paper for submission. We can start the measurement at the beginning of the next year. Kazuhiro (Yamamoto) add this topic to Microsoft Project.

Material

Tokoku-san investigates where we can measure magnetism and asks measurement or measures.

17 Dec. 2013

033

2013 Dec. 10

T. Suzuki

Closed. He collected information (KOBELCO and Nippon Steel and Sumitomo Metal). Diameter is between 1 mm and 250 mm. Typical length is 4000mm.

Material

Suzuki-san asks companies (for example, http://www.ofa-titanium.com/product/titan/ti64.html) what kinds of geometry of Ti-6Al-4V are possible.

034

2013 Dec. 10

C. Tokoku, T. Suzuki

Urgent! Ti-6Al-4V bar will be delivered tomorrow. Other parts are at ICRR. Suzuki-san will bring stainless wire in this week.

Material

Tokoku-san prepares the mockup to research how to install wire between room and cryogenic temperature by end of next week. First of all, she checks where it will be in 101. Duct could be made from plastic. Wire is titan or its alloy. Suzuki-san prepares the stainless wire.

20 Dec. 2013

035

2013 Dec. 10

Urgent! Kazuhiro consults with Ettore.

Material

Monitor system to check whether the wire between room and cryogenic temperature touches the cryoduct.

036

2013 Dec. 10

T. Suzuki, S. Koike

Urgent!

Material

Suzuki-san checks result of Koike-san’s calculation to evaluate the deformation of radiation shield after evacuation for design of cryoduct on radiation shield top.

037

2013 Dec. 10

Y. Sakakibara

Closed.　He summarized. Calculation of thermal radiation from SAS hole

Material

Yusuke calculate how the radiation into shield depends on the diameter of cryoduct.

17 Dec. 2013

038

2013 Dec. 10

D. Chen, R. Takahashi, T. Sekiguchi, E. Majorana

Closed. He summarized result Cryogenic meeting status report on 2013/12/17 (Control). The mass moved by stepping motor is on the order of kg.

Control

Dan will consult Takanori, Ryutaro and Ettore (how to evaluate the requirement for stepping motor for Type B or Virgo ? )

17 Dec. 2013

039

2013 Dec. 10

T. Suzuki

Closed. He reported AdhesiveTest. He recommends Nitofix. ->(#044). Othrewise, Araldite rapid.

Control

Suzuki-san reports the strength of glue for coil-magnet actuator in the next meeting.

17 Dec. 2013

040

2013 Dec. 17

R. Kumar, D. Chen

Closed. Takanori and Eiichi proposed first preliminary design. Preliminary design of Type-A suspension system.-> Rahul’s new mission (#048).

Sapphire monolithic suspension

”First design” of intermediate mass: Rahul fixs the details of sapphire blade springs. He will give information to Dan. Dan considers how blade spring and stage of stepping motor will be installed in intermediate mass and he evaluates moment of inertia.

25 Dec. 2013

041

2013 Dec. 17

S. Koike

Closed. He considered. Unfortunately, it is complicate. So, we do not investigate.

Sapphire monolithic suspension

Koike-san considers whether “cross structure” of sapphire blade spring is possible or not. If necessary, he adjusts the shape of blade spring. But if we need drastic improvement, we forget this idea.

25 Dec. 2013

042

2013 Dec. 17

R. Kumar, A. Khalaidovski

Closed. Rahul’s new mission (#048).

Sapphire monolithic suspension

Rahul improves the design of blade spring. Sascha will order.

25 Dec. 2013

043

2013 Dec. 17

K. Yamamoto

Urgent! Kazuhiro collected information, but did not summarize yet.

Overall design

Kazuhiro will ask Takashi Uchiyama how much CLIO suspension rotates during cooling.Kazuhiro Yamamoto summarizes the requirement of dynamic range of mirror position and yaw rotation because the top of Type A must be adjusted for this purpose. He also asks Takashi what happened in CLIO.

25 Dec. 2013

044

2013 Dec. 24

T. Suzuki

Urgent! Suzuki-san will reserve the out gas measurement system at KEK. For baking, the spacer between magnet and mirror is necessary because baking mirror with glued magnet causes contamination.

Control

Suzuki-san asks Saito-san whether Nitofix is ultra high vacuum compatibleOut gas.

045

2013 Dec. 24

D. Chen

Closed. He provided.

Sapphire monolithic suspension

Dan will provide information about size of stepping motor, stage and weight.

7 Jan. 2014

046

2013 Dec. 24

K. Hayama

Vertical spring

Kazuhiro Hayama evaluates the amplitude of gravitational wave from pulsars between 10Hz and 20Hz. He will take into account the direction of KAGRA interferometer and pulsars.

7 Jan. 2014

047

2013 Dec. 24

D. Chen, T. Sekiguchi, K. Yamamoto

Urgent! Dan provided his result.

Vertical spring

Dan and Takanori evaluated vibration via heat links with extra pendulum between cryo payload and cryocooler. Dan provides his shield vibration measurement result in Toshiba. Takanori will try simulation for heat links. Kazuhiro Yamamoto will give parameters.

7 Jan. 2014

048

2014 Jan. 8

R. Kumar

Urgent!

Sapphire monolithic suspension

Rahul investigates folding sapphire blade spring by 10th of Jan.

10 Jan. 2014