Summary of the week ending Aug 8th. Number of elog entries = 56
+ The vent started Wednesday morning
+ Repositioning of the green periscopes and associated mirrors are done.
+ Got both of the green beams coming out from the chambers
+ Moved the ETMX suspension tower by -8.09 inch (away from vertex)
+ Fixed the alignment of the ETMX CCD mirrors
+ Recovered the X green beam axis for the latest ETMX position
+ oplev centered prior to the vent
+ ETMY_TRANS_QPD didn't respond at all, needs to be fixed
+ Old MZ PD (InGaAs 2mm, @29.5MHz) has been modified for REFL33.
The 11MHz notch circuit is at the amp side instead of the diode side. This is ready for the installation
+ REFL165 PD has been made from the old 166MHz PD.
+ IPPOS has been sick since 19th of July, 2011
+ IPANG is clipped on a pick-up mirror on the ETMY table. QPD itself is healthy.
+ The spot positions on the MC mirrors were measured prior to the vent.
The results are almost the same as before within a few percent difference expect for the MC2 yaw.
+ An attenuator, consisting of two HWPs and a PBS, has been installed on the PSL table for the MC low power state.
+ a 10% BS in front of the MCREFL_RFPD was replaced by a perfect reflector for the low power mode.
+ The incident power for MC was decreased to 20 mW
+ The beam axis going to MC was misalgned due to the attenutor.
Then the beam was aligned by touching two steering mirrors on the PSL table
+ MC is able to be locked in air. The reflection DC goes from 1.4 to 0.13 V when the MC is locked.
+ With the mass-kicking technique, the arm lengths were measured.
Xarm = 37.5918 m, Yarm = 37.5425 m.
- Green locking
+ Y green beam is aligned to the Y arm
+ Locking of the Y green is not robust, it needs to be revisited
+ Wiener Filtering was applied on the data collected from the X-arm for a duration of 1500 seconds.
+ The hazardous waste people are moving chemicals around outside our door, and have roped off our regular front door.
+ The horizontal trolley drive of the east end crane stopped working. It will be fixed.