Reports until 23:41, Tuesday 16 December 2014
H1 ISC
kiwamu.izumi@LIGO.ORG - posted 23:41, Tuesday 16 December 2014 (15663)
HAM1 in-vac work completed

Elli, Sheila, Kiwamu,

We went in the HAM1 chamber this afternoon and completed the following tasks:

The HAM1 is ready for the door to be back on.

 

(Some notes)

We aligned the POP beam onto the diode when the PRMI was locked on the sidebands, 10W. The beam was visible on a laser card so that it was not a difficult job (though we had to spend sometime trying to re-acquire the PRMI lock). I steered the picomotor that was in front of POP_A to center the beam. After we coarsely adjusted the mirror, we then did a fine adjustment by looking at dataviewer and brought the beam to the center of the PD. This was done by locking a simple Michelson as this was easier to lock and bright enough to see the POP DC signal in the digital system. The beam dump was already in the designed position and I steered the reflection to the dump by rotating the POP_A diode, probably by 1 or 2 deg. Note that at the beginning, beam was barely hitting the dump.

Since none of the pico motors had the collars or kapton washers installed, we installed them this time. After the installation, three picomotors, out of four, still had a room of more than 5 mm in the thread. The last one in front of POP_A had approximately 2 mm in the thread both pitch and yaw.  We opened and closed both REFL and POP beam diverters to make sure that they don't easily get stuck. We did 5 or 6 times of open/close operations and they did not fail.

After we finished the in-vac work, we realigned the PRMI and locked it on the sidebands. We confirmed that the POP was still receiving the light.