J. Oberling, E. Merilh

Today we swapped the glitching BS oplev laser with one that has been stabilized.  Old laser SN 130-1, new laser SN 129-2.  This laser will thermally stabilize over the next 4-6 hours or so.  Once this is done, I will evaluate it to see if we need to do any small power tweaks to acheive stable operation (this is because the thermal environment in the LVEA differs from the lab the laser was stabilized in).

We also adjusted the whitening gain at the BS whitening chassis to suit the new laser.  The old SUM counts were ~75k with 15 dB of whitening gain.  After adjustment the new SUM counts are ~34k with a whitening gain of 9 dB; this is safer as we won't cause saturation if all the light happens to fall on one quadrant of the QPD.  A picture of the Output Configuration Switch is attached and these changes are captured here: T1500556-v2.

This completes WP #5651.

I reset the 35W FE watchdog today at 17:34 UTC (9:34 PST).

We have lost lock a few times when the SR3 cage servo becomes railed, and sometimes while trying to releave.

Since there is more range, I moved the actuation to M1 (WP 5657).  Since we use M1 TEST P for alingment offsets, I used M1 DITHER instead.  I reduced the gain from 300 to 1, this seems to be working fine.  

TITLE:  12/15 OWL Shift 08:00-16:00UTC (00:00-08:00 PST), all times posted in UTC

STATE Of H1: Down for Maintenance

SUPPORT:

END-OF-SHIFT SUMMARY: One lockloss towards the end of shift due to an earthquake in Vanuatu. Otherwise it's been a quiet night. Sheila arrived early to measure some transfer function so Maintenance started early (LLO was already down). Mike wasn't very happy. Reminder to all the operators to check with him before making such decision.

Activity:

14:00 Richard driving down Y arm to check on some bright light.

14:40 Stopped at ENGAGE_ASC_PART3 for Sheila

15:55 Lockloss. Sheila's driving ETMs.

16:00 Jeff B. driving a folklift from LSB to warehouse.

Sheila arrived and has started working on WP#5563 (driving the ETMs). Since LLO is down I guess our Maintenance can start early.

Not sure what happen here. ASC loop won't engage.

Cause not obvious. I don't see anything harmful looking in the environment channels except for the traffic is picking up on Rt.10.

Still Observing and going strong. Low wind (near 0mph). Useism is stabilizing at 50th percentile. 501.749 Hz violin mode is high but not ringing up as far as I can tell (now ~3 order of magnitudes above its noise floor).

TITLE:  12/14 EVE Shift:  00:00-08:00UTC (16:00-00:00PDT), all times posted in UTC     

STATE of H1:   NLN @ 80Mpc.

Incoming Operator:  Nutsinee

Support:  Sheila On Phone at beginning of shift

Quick Summary:

C. Cahillane

I have produced the total LHO uncertainty budget, now including Pcal sensing information at 1 kHz and 3 kHz. (Thanks Shivaraj!)

C01 means the kappas were left uncorrected in the uncertainty propagation.  C02 is the "perfect" calibration model, with kappas corrected.
C00 is the "nominal" model output by the front end, which has uncorrected kappas AND static frequency dependent systematics left in.

PDFs 1 and 2 each contain nine plots.  Plots 8 and 9 are the total magnitude and phase uncertainty in strain.  Plots 6 and 7 are the components that make up the uncertainty.  Plot 1 is the C00 response divided by either the C01 or C02 response to show the frequency dependent systematic errors that were corrected.

PDF 3 is the sensing measurements and fits.  (We have a nonlinear fit for the sensing function magnitude, which results in this dominating the uncertainty budget.)
PDF 4 is the actuation measurements and fits.

PDF 5 is the direct comparison of C01 and C02.  This basically shows the total effect correcting the kappas has on the response function.

LHO has a total uncertainty under 6% and 3.5 degrees  (See plots 8 and 9 from PDF 2)

For the LLO budget please see aLOG 23573

This is per the Ops Daily Check Sheet for a task to be done by a Monday Operator.

Laser Status:
SysStat is good
Front End power is 30.93W (should be around 30 W)
Frontend Watch is GREEN
HPO Watch is RED

PMC:
It has been locked 20.0 days, 13.0 hr 48.0 minutes (should be days/weeks)
Reflected power is 1.751Watts and PowerSum = 24.67Watts.

FSS:
It has been locked for 0.0 days 1.0 h and 21.0 min (should be days/weeks)
TPD[V] = 1.429V (min 0.9V)

ISS:
The diffracted power is around 8.255% (should be 5-9%)
Last saturation event was 0.0 days 1.0 hours and 21.0 minutes ago (should be days/weeks)

Intentionally dropped from Observing Mode to address SR3 Cage Servo, but then accidentally had a lockloss while addressing this servo.  Out of Observing for roughly 3hrs.  Here's timeline:

• 1:30  Dropped out of Observing to address SR3 Cage Servo, but....
• 1:31  Lockloss due to SR3 Cage Servo fix
• 1:31 - 1:45  Fixing SR3 Cage Servo
• 1:47 - 2:36  Initial Alignment
• 2:36 - 4:21  Lock Acquisition
  • 3:02  Missed GRB
• 4:26  Back to Observing

For Initial Alignment noticed the ALS arms were off in pitch and ugly, but after taking care of them, only other noticeable variance was the Dark Michelson was also off in pitch.  Restored this by looking at the AS Camera and the AS_C medm window's QPD, and steering the SR2 in pitch quite a bit (from 1938 to 2022); but this is what was needed to bring the spot back down in the center of the camera.  From here on, it was normal work.

Locking was usual time sink when we have high useism (but it's dropping).  During one drop, Guardian was in the middle of DC_READOUT_TRANSITION & giving OMC not locked error.  I re-requested READY_FOR_HANDOFF, but H1 dropped.  Think next time, we should select DC_READOUT_TRANSITION on the ISC_LOCK guardian (instead of having NOMINAL_LOW_NOISE), so that we don't fight the Guardian while locking the OMC.

At this point, we could have opted to try the new FULLY_ISOLATED state for the BS ISI, but we had been out of Observing for so long, that we decided to hold this off until Maintenance tomorrow.

H1 made it to NLN on the next lock.  There were a few known SDF diffs:  BS ISI time ramps (which I returned to 0sec), and the new filters Evan added for the test mases (I ACCEPTED these).

Over last 12hrs, useism has been trending down (and maybe flattening for the last 2hrs) and is at ~0.4um/s for the LVEA & winds are hovering below 10mph.