|
Size: 3728
Comment:
|
Size: 3737
Comment:
|
| Deletions are marked like this. | Additions are marked like this. |
| Line 11: | Line 11: |
| Line 12: | Line 13: |
| [[BR]] |
Arm Length Stabilization by injecting green laser beams from the arm ends
<<TableOfContents: execution failed [Argument "maxdepth" must be an integer value, not "[2]"] (see also the log)>>
aLIGO ALS wiki http://ilog.ligo-wa.caltech.edu:7285/advligo/Arm_Length_Stabilisation
Plan
time line
time line describes where we are now and where we go.
Conceptual design
Description of the optical / servo configuration [https://dcc.ligo.org/cgi-bin/private/DocDB/ShowDocument?docid=6888 LIGO DCC]
Servo modeling (SimLink) [https://nodus.ligo.caltech.edu:30889/svn/trunk/docs/upgrade08/Green_Locking/Servo_modeling/ 40mSVN]
Green Preliminary Design
Development roadmap
End table arrangement
- NPRO placement / optical assembly at the end
- SHG at the end table
- Control system placement
- Coarse alignment to the cavity
- Fine alignment
- Lock of the green beam to the cavity
At the PSL table
- SHG at the PSL table
Digital control
- Virtual Green lock by RCG
- GPIB interfaces
Vertex tank optical arrangement
- In-vac steering (PO transmission / Periscope / Mirrors)
- Vertex phase noise measurement
- Electronics placement
- Control system implementation
Performance evaluation
- f_noise of green beam / PDH performance
- Relative f_noise between the PSL green and the Arm transmitted green
- ALS performance
Sophistication of the scheme
- Automatic handing off scripts
- Ready-to-go panels for AdvLIGO
- Automatic alignment of the green beam
- ---
- Green Michelson for precise ETM calibration
Absolute length / mode spacing measurement by green
Detailed design
Design and Purchasing Lists
Detailed considerations
- Optical Layout ([attachment:green_optics.png Table]/ In-vac)
Periscopes for beam steering from PR3/SR3 transmissions to the PSL viewport
- PSL viewport modification (viewport cover / tube / PSL box / periscope on the PSL table)
- PSL table
Laser & SHG specs --- power, polarization, Xtals
- references
[1] G.D.Boyd and D.A. Kleinman, [http://jap.aip.org/japiau/v39/i8/p3597_s1 "Parametric interaction of Focused Gaussian Light Beams", J.A. Phys. 39, 3597 (1968)]
[2] C. Zhang, Y.Qin and Y.Zhu, [http://www.opticsinfobase.org/ol/abstract.cfm?uri=ol-33-7-720 "Perfect quasi-phase matching for the third-harmonic generation using focused Gaussian beams",Opt. Lett. 33, 720 (2008)]
- Main optics specs (review)
- Mode matching ([attachment:modematch_END.png mode matching at end table])
- Green generation
- [attachment:manual_oven.pdf manual for the covesion oven]
- Expected performance / noise / control system range
- Digital servo / operation
- Alignment (initial / fine / automatic)
- Optical Layout ([attachment:green_optics.png Table]/ In-vac)
Control information
