Reports until 11:59, Tuesday 18 November 2025
H1 PSL
jason.oberling@LIGO.ORG - posted 11:59, Tuesday 18 November 2025 (88161)
PSL FSS RefCav Remote Beam Alignment Tweak

The RefCav Refl spot was off this morning and the TPD had been trending down the last several days, so I took the opportunity to tweak the beam alignment into it from the Control Room.  The ISS was ON for this work.

When I started the RefCav TPD was ~0.520 V and when I finished the TPD was ~0.548 V.  I then noticed the ISS was diffracting ~4.5%, which is higher than its norm, so I adjusted the ISS RefSignal to -2.01 V from -2.00 V.  This brought the diffracted power % down to around its normal value of ~4%.  At this diffraction % the RefCav TPD is now ~0.550 V and the PMC Trans is now ~106.9 W.