Reports until 15:01, Tuesday 30 May 2017
H1 ISC
daniel.sigg@LIGO.ORG - posted 15:01, Tuesday 30 May 2017 - last comment - 11:47, Wednesday 31 May 2017(36528)
EX ALS laser swapped

Temp A: 24.4 ºC
Temp B: 21.6 ºC
Diode: 1.80A
Laser Crystal Temp: 29.60 ºC
Doubler Temp: 33.62 ºC

Images attached to this report
Comments related to this report
daniel.sigg@LIGO.ORG - 15:14, Tuesday 30 May 2017 (36529)

Changed set points:

H1:ALS-X_FIBR_A_DEMOD_RFMAX: 10 from 4
H1:ALS-X_FIBR_LOCK_BEAT_RFMIN: -10 from -15
H1:ALS-X-LASER_HEAD_LASERDIODEPOWERNOMINAL: 1.80
H1:ALS-X-LASER_HEAD_LASERDIODEPOWERTOLERANCE: 0.2

daniel.sigg@LIGO.ORG - 15:21, Tuesday 30 May 2017 (36530)

The cable to the H1:ALS-X_LASER_IR_DC photodetector is intermittent and needs to be re-terminated. Currently, the readback is broken.

keita.kawabe@LIGO.ORG - 18:19, Tuesday 30 May 2017 (36541)

S/N (on the controller) Pulled out -> 2011B, Installed -> 2011A

Interlock cable was installed by Filiberto.

Handles on the controllers were swapped as the new one didn't have the tapped holes necessary for mounting on the table enclosure extension. The untapped handles will be drilled and tapped later.

sheila.dwyer@LIGO.ORG - 19:31, Tuesday 30 May 2017 (36544)

Kiwmau and I went out the end station after they swapped the laser and tweaked the beatnote alignment. We ended up with more power on the BBPD than before the laser swap (20mW now  compared to 19mW  from the old laser before the power dropped on sunday evening.)  We also moved the lens in the laser path before teh beatnote beam splitter 1.5 inches closer to the beamsplitter. This increased the beat note power to 8dBm, compared to about 0dBm from the old laser before Sunday evening. 

kiwamu.izumi@LIGO.ORG - 05:37, Wednesday 31 May 2017 (36554)

After we finished up the hardware work on the ISCTEX table, Jenne and Ed aligned the X arm for the green laser, which resulted in a highest (normalized) transmission of roughly 0.8 when it was fully resonant. Therefore the amount of light power reaching the corner station decreased from what it used to be by 20%. Since the output power of the new laser at that point was lower than it had been with the old laser by 10%, the half of the reduction in the transmission can be explained by the reduced laser power. I think the remaining 10% is due to mode-matching loss.

jeffrey.kissel@LIGO.ORG - 11:47, Wednesday 31 May 2017 (36564)CDS
Opened FRS Ticket 8249 regarding broken readback of ALS X IR PD.