Since Cheryl mentioned there were issues with running an alignment at the PRC step, decided to endeavor to run an alignment "by-hand" (i.e. the way we used to do it before the new INIT_ALIGN guardian automated most of the alignment.
Not totally sure how to detach the new automated aligning guardian, INIT_ALIGN from alignment. Tried taking it Manually to IDLE, but When I selected INITIAL ALIGNMENT on ISC LOCK the INIT_ALIGN guardian looked to jump into action. So next up I took INIT_ALIGN to an OP state of STOP, which moved to PAUSE (one of these steps turns the node YELLOW), and this looks liked it allowed me to keep running a manual alignment.
0) 8:01utc: ISC_LOCK to INITIAL_ALIGNMENT
1) Green Arms: Aligned these normally and with no issues
2) Input Align: Offloaded normally & completed.
3) PRC: Walked through each step since there were issues with this earlier. Notes below.
- When prepping for PRC, Cheryl noticed the IMC unlocked during the PREP_FOR_PRX step
- Finally completed PREP_FOR_PRX, so selected the next step of ACQUIRE_PRX, but it would not acquire (this step remained "orange")
- Also worth noting the gain used was -5200 (for H1:LSC-PRCL1_GAIN)
- Changed PRCL1 gain to -520000 by hand, but the H1:ASC-AS_A_DC_NSUM signal became flat (i.e. doesn't look like locking).
- Tried gain of -5250000, but this had no change either.
- ALIGN_IFO to DOWN to try tweaking PRM alignment by hand the old way PRM was at pit = -1488.5 & yaw = -418.3
- So looked at AS_A signal and worked on "making highs higher & lows lower" & this required a HUGE pitch shift (i.e. pit = -1599 & yaw was small) for PRM (see attached)
- Tried ACQUIRE_PRX again and no locking with -5200 gain.
- Tried gain of -520000 and then it eventually locked.
- PRX_LOCKED--->OK
- WFS_CENTERING_PRX--->OK
- PREP_PRC_ALIGN--->OK
- PRC_ALIGN--->looked ok...waited for signals (PRC1 pit & yaw) to converge & they did
- OFFLOAD_PRC_ALIGNMENT--->OK
- PRC_ALIGN_OFFLOADED--->OK
4) MICH_BRIGHT_OFFLOADED---went to DOWN and stayed there...so moved to....
5) The old MICH_DARK_ALIGN
- Tweaked BS by hand to align AS AIR spot & minimize AS_A
- And it looks like it needs a HUGE pitch!!
- Side note, while making the big pitch moves on BS, I increased the "increment" from the usual 0.03 to 0.1, but when I clicked on the Pitch slider, the slider went immediately from around 186 to 730!! Immediatley took BS pit back to 186 by hand, but I had NO spot at all on AS_AIR!! So I ran the DOWN and tried again. It eventually came back after running DOWN twice more. :-/ Since it was not getting to MICH_DARK_ALIGN, I had to take it to the original BS pitch value which was 189.7.
- Seemed to like a pitch of 182.7, but still not that great looking on the video.
- Best I could do by hand was pit = 190.27 & yaw = -332.97
6) For kicks, tried MICH_BRIGHT_OFFLOADED (because maybe it was not in a closer alignment for it to work this time)---Guardian completed this time!--->OK
7) SRC--->SRC_ALIGN_OFFLOADED----Guardian completed these steps on its own---> OK
- Was fine up to SRC_ALIGN, but then moved down to WFS_CENTERING_SRY again.....and while here could see SRC2 signals appear and converge....but then we just stayed at WFS_CENTERING_SRY, so
- So then moved through remaining steps by selecting them by hand on ALIGN_IFO according to what the "graph" shows (i.e. PREP_SRC_ALIGN -> SRC_ALIGN -> OFFLOAD_SRC_ALIGNMENT -> LOWER_POWER ->SRC_ALIGN_OFFLOADED)
8) 9:53utc Alignment COMPLETE (ISC_LOCK taken to DOWN): At this point, this very long by-hand alignment was complete! Returned INIT_ALIGN to EXEC
NOTE: I did not make any change to lscparams.py file. So that PRXY gain is still at the low value of -5200 (atleast for my by-hand alignment).
where nV is the voltage noise floor, T is the transimpedance, e is the electron charge, R is the responsivity of e λ/(h c) = 0.858 A/W, QE is the quantum efficiency of 0.9, PDC is the DC power from the incident light, and Pdet is the power apparent from the intrinsic detector noise (i.e. the incident power where shot and dark noise are equivalent).
We fit the measured shot and dark noise spectra for IMC REFL I/Q, REFL_A 9I/Q, REFL_B 9I/Q, and at the CARM and IMC servo board OUT2 locations with the nominal gain slider settings (OUT2 connected to IN1, CMB IN1GAIN = 6 dB, IMC Board IN1Gain = 28 dB). REFL_A spectra are plotted in attachment 3 as an example.
For dark noise I shuttered the PSL. For shot noise I measured with 1W, 2W, and 4W input requested power, and recorded how much light was reported by the LF channels:
15:01 PEM injections are done.