I aligned FPMI and greens. There's no recognizable difference between before and after the vent.
What I did:
1. Aligned Y arm to maximize Y green transmission.
2. Used PZT1/2 to maximize TRY. But since PZT1 doesn't work so much, I had to align Y arm, too (mostly ETMY). This decreases green transmission, but I will leave it.
3. Aligned BS and X arm to maximize TRX
4. Fine tune them to minimize ASDC during FPMI lock, without decreasing TRX
5. Aligned X end green to get TEM00 transmission.
Now, TRY and TRX are both ~0.89.
Green transmission from Y and X arm are ~123 uW and ~275 uW respectively. Their max we got so far was ~200 uW and ~255 uW.
I still see clipped beam at AS, which I think is from the Faraday edge, as we found in elog #6897.
Below is the Sensoray capture of some ports, and MEDM screen shots to compare with before vent(see #6893).
There are two AS captures, one is without MI lock and the other is with MI lock. Note that PRM/SRM is misalined.
 
Next:
- I will check ALS
- I keep Y end green optics untouched since elog #6776, to use it as a reference. We need to realign them if tip-tilts are installed in vacuum, or PZTs are installed in both ends. |