Reports until 20:34, Thursday 05 December 2013
H1 IOO (ISC)
kiwamu.izumi@LIGO.ORG - posted 20:34, Thursday 05 December 2013 - last comment - 09:11, Friday 06 December 2013(8851)
IMC left locked

I am leaving the IMC locked for the night in order to see its stability. The ASC loops are all engaged.

It must be rock-solid because we fixed the EOM !!

An auto-locking script is locally running on opsws4. The script itself resides in /opt/rtcds/userapps/release/ioo/h1/scripts/imc/sballmer/ and it is called MClockwatch.

Comments related to this report
kiwamu.izumi@LIGO.ORG - 08:14, Friday 06 December 2013 (8855)

We obtained a 9 hours of overnight lock stretch. It dropped the lock at 7:55 am in this morning for some reason which I haven't investigated yet.

At 10 pm local last night, I found that the ref cav was having a trouble in relocking. It was due to a too low transmitted light, resulting in a non-ideal trigger for relocking. Probably some optics drifted and misaligned. I decreased the threshold from 0.9 to 0.7. Then FSS started locking fine.

The attached is trend of 12 hours from this past night.

Images attached to this comment
kiwamu.izumi@LIGO.ORG - 09:11, Friday 06 December 2013 (8856)PSL

Indeed, the alignment of the reference cavity somewhere got drifted. It seems that it is mainly in pitch. It is visible in the ref can reflected camera -- see the attached picture. The reflected light started showing a halo on the upper side.

Figure: Quad view of the PSL cameras, taken at around 9 am. this morning (6/December/2013)

RefCav Trans

PMC Refl
RefCav Refl PMC Trans

Table: Quad video's signal assignment.

 

BTW, you can now take a picture of the videos by running Chris's excellent script:

/ligo/home/christopher.wipf/Public/Data/2013-11-20_video/gst-camera-framecapture

Of course, this is a temporary place and we will move this script to somewhere appropriate at some point.

Images attached to this comment