1 / 30

Lessons from CLIO

Lessons from CLIO Masatake Ohashi (ICRR, The University of TOKYO) and CLIO collaborators GWADW2012 Hawaii 2012/5/16. Contents. CLIO Outline Lessons from CLIO Radiation shield Alignment monitor Heat switch Status of CLIO Summary. CLIO: Prototype for KAGRA. Overview of CLIO.

zlata
Download Presentation

Lessons from CLIO

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Lessons from CLIO Masatake Ohashi(ICRR, The University of TOKYO)andCLIO collaboratorsGWADW2012Hawaii2012/5/16

  2. Contents CLIO Outline Lessons from CLIO Radiation shield Alignment monitor Heat switch Status of CLIO Summary GWADW2012 Hawaii 2012/05/16

  3. CLIO: Prototype for KAGRA GWADW2012 Hawaii 2012/05/16

  4. Overview of CLIO GWADW2012 Hawaii 2012/05/16

  5. CLIO Optical configuration 12MHz mod Locked Fabry-Perot IFO Length: 100m. Finesse: 3000. Cavity pole: 250Hz. Beam radius; Near mirror: 4.9mm. End mirror: 8.5mm. FB Innolight MEPHISTO 1064nm, 2W 15MHz mod One Mode Cleaner; Length: 9.5m. Finesse: 1800. Mod. transmission control. FB 100m FP for Frequency stabilization Mode Cleaner Test mass; Substrate: Sapphire. CRYSTAL SYSTEMS Φ100×60mm, 1.8kg. Polished by CANON Coated by JAE 100m FP for GW detection FB GWADW2012 Hawaii 2012/05/16

  6. Lesson 1 1. It was not easy to cool the mirrors. GWADW2012 Hawaii 2012/05/16

  7. Difficulties of cooling Thermal conduction is the only method for cooling. Mirrors are in high vacuum (10-5Pa) and low temperature. No convection and no radiation for heat transfer. Mirrors are vibration isolated. Low suspension thermal noise is necessary. GWADW2012 Hawaii 2012/05/16

  8. Cooling method by a cryocooler GWADW2012 Hawaii 2012/05/16

  9. Suspension for cooling Final suspension wire(FSW). 300K: Bolfur of Φ0.05. Cryogenic: Al wire of Φ0.5. Three heat link wires(H1-3). Cryogenic: Al wire of Φ0.5. Two thermometers for monitoring. Attached on clamping points of H1. Suspended mirror was housed in a cage prevent from radiation heat. H3 H2 H1 FSW 400mm GWADW2012 Hawaii 2012/05/16

  10. Cryogenic suspension GWADW2012 Hawaii 2012/05/16

  11. Intermediate Mass GWADW2012 Hawaii 2012/05/16

  12. Lesson 1 1. It was not easy to cool the mirrors. 2. It was difficult to cool the mirrors. GWADW2012 Hawaii 2012/05/16

  13. 300K Radiation 300K Radiation from window of Gate Valve warms mirrors Serious Problem for cooling Mirror (20K) Radiation shield (40K) 300K Radiation ( straying ) Gate Valve (300K) Good Heat Transfer, Baffles, … GWADW2012 Hawaii 2012/05/16

  14. Radiation Shields 1 Baffle GWADW2012 Hawaii 2012/05/16

  15. Lesson 1 1. It was not easy to cool the mirrors. 2. It was difficult to cool the mirrors. 3. It seemed almost impossible to cool the mirrors to 20K. GWADW2012 Hawaii 2012/05/16

  16. Radiation Shields 2 Baffle GWADW2012 Hawaii 2012/05/16

  17. Lesson 1 1. It was not easy to cool the mirrors. 2. It was difficult to cool the mirrors. 3. It seemed almost impossible to cool the mirrors to 20K. Radiation shield is essential for cooling. GWADW2012 Hawaii 2012/05/16

  18. Lesson 2 1. It takes long to cool mirrors. GWADW2012 Hawaii 2012/05/16

  19. Cooling test and achieved temperature 63K 8.8K 45K 12.9K GWADW2012 Hawaii 2012/05/16

  20. Cooling summary #1; No shield for radiation from the outer shield at 63K. GWADW2012 Hawaii 2012/05/16

  21. Lesson 2 1. It takes long to cool mirrors. 2. It is important to keep alignment. If we loose alignment, we have to warm up mirrors and adjust. GWADW2012 Hawaii 2012/05/16

  22. Cooling procedure (for example) STEP3 cooling mirror adjust alignment STEP1 cooling mirror adjust alignment STEP4 cooling mirror adjust alignment STEP2 cooling mirror adjust alignment Cooling makes mirror suspension shorter by 2mm. GWADW2012 Hawaii 2012/05/16

  23. Cooling in 2007 All mirrors are suspended by Φ0.5 Al wire. All mirrors are cooled at 12K -14K. Only inline near mirror was cooled during 07/03/16 - 04/24 using Φ1.0 Al wire. This is the first sensitivity trial with cryogenic cooled 4 mirrors. for msec noise GWADW2012 Hawaii 2012/05/16

  24. Lesson 2 1. It takes long to cool mirrors. 2. It is important to keep alignment. Wave Front Sensor is necessary. GWADW2012 Hawaii 2012/05/16

  25. Lesson 3 How about heat switch system ? GWADW2012 Hawaii 2012/05/16

  26. Heat switch To reduce cooling time, we tried to use heat switch. ON : high heat transfer OFF: low heat transfer But we failed. GWADW2012 Hawaii 2012/05/16

  27. Cryostat for an end mirror GWADW2012 Hawaii 2012/05/16

  28. Lesson 3 How about heat switch system ? Low heat flow is essential. GWADW2012 Hawaii 2012/05/16

  29. Status of CLIO CLIO noise spectrum with cryogenic mirror became below that with room-temperature mirror. Phys. Rev. Lett. 108, 141101 (2012) GWADW2012 Hawaii 2012/05/16

  30. SUMMARY We demonstrated to operate interferometer with cryogenic mirrors by CLIO, but careful setup is necessary for cooling. GWADW2012 Hawaii 2012/05/16

More Related