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Entry  Tue Feb 15 17:48:22 2011, Jenne, Update, IOO, Mode Cleaner resonating again 
    Reply  Tue Feb 15 21:45:08 2011, rana, Update, IOO, The MC TRANS Story a.png
Message ID: 4303     Entry time: Tue Feb 15 17:48:22 2011     Reply to this: 4304
Author: Jenne 
Type: Update 
Category: IOO 
Subject: Mode Cleaner resonating again 

[Valera, Jenne]

After Steve and Valera switched out the PMC, the Mode Cleaner resonance needed to be brought back.  We spent some time playing with the 2 steering mirrors directly after the PMC, to get the beam through the EOM, and to achieve flashing in the MC.  Valera then adjusted those 2 steering mirrors to minimize MC_REFL_DC.  I did a little bit more, and it's kind of close now, but we're only at ~half normal transmitted power.  Since the 2 steering mirrors after the PMC are so close together, the beam alignment is pretty sensitive to even small touches.  So it's probably time to move on to using the last zigzag steering mirrors on the PSL table, since they're farther apart. 

I have to head out for a little while, but I'll be back in a few hours. Kiwamu said he might continue the alignment into the MC, if he needs the IFO.  Also, we should measure the power before and after the EOM, just to confirm that we're getting through it optimally.  The beam looks good after the EOM, and the MC is resonating, so it should be fine, but it can't hurt to check.

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