I started this document on my own with notes as I was tracing the beam path through the output optics, as well as some notes as I started digging through the elogs. Let's just put it here instead....
- Beam from AS port into OMMT
- Reflect off OM5-PJ
- TO DO: check that the PZT works
- 40/P/F/L, 1525-45-P
- Pick off from OMPO
- TO DO: determine how much power is needed for the pick off, choose an appropriate optic (for this vent probably 50-50 is fine)
- The PO beam goes to OM6
- Reflect off MMT1???
- TO DO: determine if this mirror has a PZT, get it working
- Has a PZT?
- Which PZT channel on the DAQ?
- Is there a cable going to from the DAC to the PZT?
- Is the PZT functional?
- How many PZTs does this mirror actually have?
- TO DO: determine the real name of this optic, find its recent history in the elog
- TO DO: determine the correct telescope parameters to optimally couple into the mode cleaner given the following:
- TO DO: look up how the radius of curvature (RC) of the OMC has changed, and therefore what telescope parameters are necessary
- Focused by MMT2???
- TO DO: determine if this mirror has a PZT
- Has a PZT?
- Which PZT channel on the DAQ?
- Is there a cable going to from the DAC to the PZT?
- Is the PZT functional?
- How many PZTs does this mirror actually have?
- TO DO: determine the real name of this optic, find its recent history in the elog
- TO DO: what about this optic is tunable? It looks bulky
- Columnated by MMT3???
- TO DO: determine if this mirror has a PZT
- Has a PZT?
- Which PZT channel on the DAQ?
- Is there a cable going to from the DAC to the PZT?
- Is the PZT functional?
- How many PZTs does this mirror actually have?
- Steered by MMT4???
- TO DO: determine the real name of this optic
- TO DO: why is this optic so small? Looks different from the rest, maybe weird space constraint
- Steered by MMT5???
- TO DO: why is this optic so large compared to OMMT4?
- TO DO: is there a more space efficient way of steering this beam, or even some way that avoids having to steer with three distinct optics
- Steered by MMT6???
- TO DO: Can this optic be removed with some clever new beam path?
- Cleaned by the OMC
- TO DO: Where does the promptly reflected beam from OMC1 go after it exits the chamber?
- TO DO: check the PZTs
- Has a PZT?
- Which PZT channel on the DAQ?
- Is there a cable going to from the DAC to the PZT?
- Is the PZT functional?
- How many PZTs does the OMC actually have?
- TO DO: Determine if a new OMC configuration would be more ideal for the squeezing experiment
- This is a large task, not part of this immediate vent
- TO DO: What is done with the OMC reflection? What is done with the transmission?
- TO DO: Check the logs about how the OMC had been in use; should be mostly from rob ward
- Reflected beam goes to the next chamber
- Transmitted beam is split by OM7???
- TO DO: find the actual name of this optic
- TO DO: why does this have the R/T that is does?
- Reflected beam goes to my OMPD
- TO DO: figure out what this PD is used for, and whether we even need it
- I think this might be the camera mentioned in 40m elog 21
- Elog 42 says the 4 QPDs for the OMC have meds screens located under C2TPT—is this a clue for channel names?
- Transmitted beam is reflected to the next chamber by OM8???
- TO DO: determine the name of this optic
- TO DO: Where does this beam go? What is it used for?
- Beam Dumps to add
- Transmission through OM5? Probably don’t need…
- OMMT1 transmission
- OMMT steering mirror transmissions
- OMC transmissions? Probably not?
- OMPD transmission?
- OM8 transmission
- Green scattering off of the window where the beam goes after GR_SM5
- Backscatter from the OMC prompt reflection to the window
- Backscatter from the OMC reflection to the window
- Backscatter from the MC beam off the window (this beam just travels through this chamber, interacts with no optics; there is also what looks like a small blue beam on this diagram, so maybe need to dump that backscatter too)
- Backscatter from the PO beam from OM6 going through the chamber window
- Backscatter from IM1 out the window
- There is a small blue beam from OMMT3 that goes through this window as well, I’m not sure exactly what is is from or for, or if it is physical (there are a few of these strange blue lines, i'm probably just misreading the diagram)
- TESTS TO DO
- Characterize the PZT control
- Lock the OMC with a PZT dither lock
- Eg elog 59
- “Tap-tap-tappy-tap test” to find resonanes
- Look at combination of PDH error signal and DCPD signal???
- See elog 86 for results from initial OMC install—Nov 2007
- Check wiggling wires, etc
- TFs to check? Vertical TF?
- OMC Length check— see for eg elog 768
- ADDITIONAL TO DO
- Mode matching calculation for new radius of curvature optics—see elog 1271
- The current MMT is not the optimal configuration even for the old Rc (see 3077 and 3088)
Notes during reading elog
- Entry 590 has a labelled picture of the optics setup with OMC
- Mention of omcepics at elog 894
- Some important changes happened in elog 1823
- 1''->2'' mirror out of the vacuum--I should check whether this is still there, or if it has been moved
- [many more changes.....]
- There were at one time 2 cameras monitoring OMCT and R (see 4492, 4493)
- Some OMC PZT HV supply info is at elog 4738, 4740...
- There are some photos of the OMC table at elog 5120, and a note about moving some optics
- Not strictly about the OMC, but I really like Suresh's diagram 6756, I'll make something similar for the OMC electronics
- although it is about adding the tip tilt electronics, which I think required a new flange for the OMC chamber
- OMC stage 1 and 2 are the steering mirrors going into the OMC, and were controlled by EPICS chans (6875, 6884)
- these PZT HV supplies lived in OMC_SOUTH (or maybe 1Y3? see elog 6893), the driver in OMC_NORTH (LIGO-D060287)
- Photos of these supplies in 7696
- There are pictures of the OMC and its PZTs in 7401
- The OMC HV supply was moved to power a different set of PZTs (see 7603)
- Talk of replacing the PZTs with picomotors or tip/tilts in 7684
- More pictures of the OMC table before the OMC was 'removed' are here (8114) and in 12563/12571 Gautam links to a Picassa album with pictures from just before the beam was diverted
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