austin.jennings@LIGO.ORG - posted 12:59, Monday 21 August 2023 (72355)
Mid Shift Report
H1 has been locked for 20 hours, all systems appear stable and seismic motion is low.
H1 has been locked for 20 hours, all systems appear stable and seismic motion is low.
Mon Aug 21 10:08:31 2023 INFO: Fill completed in 8min 27secs
Travis confirmed a good fill curbside.
TITLE: 08/21 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Observing at 151Mpc
OUTGOING OPERATOR: Corey
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 3mph Gusts, 2mph 5min avg
Primary useism: 0.01 μm/s
Secondary useism: 0.18 μm/s
QUICK SUMMARY:
- H1 locked for 15.5 hours
- SEI/CDS ok
TITLE: 08/20 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Observing at 151Mpc
INCOMING OPERATOR: Corey
SHIFT SUMMARY: Quiet shift; recovered from last shift's EQ lockloss and kept observing throughout. H1 has now been locked for 7.5 hours.
LOG:
No log for this shift.
State of H1: Observing at 153Mpc
H1 was able to relock automatically following the lockloss from the last shift and has now been observing for 3.5 hours.
TITLE: 08/20 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Lock Acquisition
OUTGOING OPERATOR: Austin
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 6mph Gusts, 4mph 5min avg
Primary useism: 0.03 μm/s
Secondary useism: 0.19 μm/s
QUICK SUMMARY: H1 is relocking following an earthquake-caused lockloss, currently up to ENGAGE_ASC_FOR_FULL_IFO
TITLE: 08/20 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Lock Aquisition
INCOMING OPERATOR: Ryan S
SHIFT SUMMARY:
- 20:19 - inc 5.7 EQ from South Sandwich Islands
- Superevent S230820bq - call received at 21:26 UTC, no alert on verbal
- 21:43 - inc 5.0 EQ from SoCal
- H1 did an auto initial alignment, just completed and now relocking as I leave the IFO to Ryan S.
LOG:
No log for this shift.
Lockloss @ 21:47, caused by local EQs.
H1 has been locked for 45 hours. Nothing to note locally, but we just got an alert for a 5.7 EQ from South Sandwich Islands region.
Sun Aug 20 10:06:46 2023 INFO: Fill completed in 6min 42secs
TITLE: 08/20 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Observing at 149Mpc
OUTGOING OPERATOR: Corey
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 7mph Gusts, 4mph 5min avg
Primary useism: 0.01 μm/s
Secondary useism: 0.16 μm/s
QUICK SUMMARY:
- H1 still going strong, right now at a 39:45 hour lock
- Systems stable, ground motion low
- Optics lab dust monitor alarm on alert handler - possibly wild fires?
TITLE: 08/19 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Observing at 150Mpc
INCOMING OPERATOR: Corey
SHIFT SUMMARY:
H1 has now been locked for 32 hours. Very quiet evening with observation time throughout.
The EY VEA dust monitor alarm started up again shortly after mid-shift. Attached is a trend of the dust counts over the past 8 hours.
LOG:
No log for this shift.
State of H1: Observing at 150Mpc
H1 has now been locked for 28 hours. Quiet evening on site; the EY VEA dust monitor alarm has stopped.
TITLE: 08/19 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Observing at 152Mpc
OUTGOING OPERATOR: Austin
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 17mph Gusts, 15mph 5min avg
Primary useism: 0.05 μm/s
Secondary useism: 0.16 μm/s
QUICK SUMMARY: H1 has now been locked for 24 hours.
TITLE: 08/19 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Observing at 152Mpc
INCOMING OPERATOR: Ryan S
SHIFT SUMMARY:
- EY DM 1 (H1:PEM-EY_DUST_VEA1_300NM_PCF) has been intermittently going off on alert handler - possibly due to wildfires, scope attatched
- Superevent S230819ax - call received at 17:21 UTC, no alert on verbal
- Overall a very quiet (and smoky) day, leaving the IFO to Ryan S. just under a 24 hour lock
LOG:
No log for this shift.
H1 still locked for 20 hours now. Systems appear stable, ground motion is still low.
Sat Aug 19 10:08:43 2023 INFO: Fill completed in 8min 39secs
Genevieve, Lance, Robert
To further understand the roughly 10Mpc lost to the HVAC (https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=72308), we made several focussed shutdowns today. These manipulations were made during observing (with times recorded) because such HVAC changes happen automatically during observing and also, we were reducing noise rather than increasing it. The times of these manipulations are given below.
One early outcome is that the peak at 52 Hz in DARM is produced by the chilled water pump at EX (see figure). We went out and looked to see if the vibration isolation was shorted, it was not, though there are design flaws (the water pipes arent isolated). We switched from CHWP-2 to CHWP-1 to see if the particular pump was extra noisy. CHWP-1 produced a similar peak in DARM at its own frequency. The peak in accelerometers is also similar in amplitude to the one from the water pump at EY. One possibility is that the coupling at EX is greater because of the undamped cryobaffle at EX.
Friday HVAC shutdowns; all times Aug. 18 UTC
15:26 CS SF1, 2, 3, 4 off
15:30:30 CS SF5 and 6 off
15:36 CS SF5 and 6 on
15:40 CS SF1, 2, 3, 4 back on
16:02 EY AH2 (only fan on) shut down
16:10 EY AH2 on
16:20 EY AH2 off
16:28 EY AH2 on
16:45 EY AH2 and chiller off
16:56:30 EY AH2 and chiller on
17:19:30 EX chiller only off, pump stays on
17:27 EXwater pump CHWP-2 goes off
17:32: EX CHWP-2 back on chiller back on right after
19:34:38 EX chiller off, CHWP-2 pump stays on for a while
19:45 EX chiller back on
20:20 EX started switch from chiller 2 to chiller 1 - slow going
21:00 EX Finally switched
21:03 EX Switched back to original, chiller 1 to chiller 2
Turning Roberts reference to LHO:72308 into a hyperlink for ease of navigation. Check out LHO:72297 for a bigger picture representation of how the 52 Hz peak in the broader DARM sensitivity, and from the Time Stamps in Elenna's plots, they were taken at 15:27 UTC, just after the corner station (CS) "SFs 1, 2, 3, 4" are off. SF stands for "Supply Fans" i.e. those air handler unit (AHU) fans that push the cool air in to the LVEA. Recall, there are two fans per air handler unit, for the two air handler units (AHU1 and AHU2) that feed the LVEA in the corner station. The channels that you can use to track the corner station's LVEA HVAC system are outlined more in LHO:70284, but in short, you can check the status of the supply fans via the channels H0:FMC-CS_LVA_AH_AIRFLOW_1 Supply Fan (SF) 1 H0:FMC-CS_LVA_AH_AIRFLOW_2 Supply Fan (SF) 2 H0:FMC-CS_LVA_AH_AIRFLOW_3 Supply Fan (SF) 3 H0:FMC-CS_LVA_AH_AIRFLOW_4 Supply Fan (SF) 4
My Bad: -- Elenna's aLOG is showing the sensitivity on 2023-Aug-17, and the Robert logging of times listed above are for 2023-Aug-18. Elenna's demonstration is during Robert's site-wide HVAC shut down 2023-Aug-17 -- see LHO:72308 (i.e. not just the corner as I'd errantly claimed above.).
For these 2023-Aug-18 times mentioned in this LHO aLOG 72331, check out the subsequent analysis of impact in LHO:72778.
Lance, Genevieve, Robert
PEM injections
We are redoing part of the formal PEM injection program, which took place for a week before the run, because the 75-60W change reduced vibration coupling by factors of 2 or 3. On Wednesday, during the commissioning slot, we finished acoustic injections at EY and started shaker injections at EY. Thursday we finished the main shaker injections at EY.
ETMY bias sweep with electronic ground injections
Fig. 1 shows that the ETMY bias setting that minimizes our electronic ground injection coupling has possibly changed a little, but not much, since January.
HVAC shutdown
I shut down the HVAC, site-wide, from about 15:23 to 15:37 Aug 17 UTC. The range increased by a little less than 10 Mpc to a little over 160 Mpc. Elenna posted a spectrum for the best part of the site-wide shutdown (see below). The shutdown and especially the re-start took time, so Fig. 2 shows just the effect of of the chilled water system at EX. Also, we shut down SF4 only (the fan pushing 11,000 CFM at the CS, from 21:18 to 21:32 UTC, but we did not see an improvement in range. We will continue with a focussed study tommorrow in order to better understand the locations of the problems.
For the ASD of GDS-CALIB_STRAIN of Elenna's that Robert mentions comparing the HVAC ON vs. OFF times see LHO:72297.
Robert did an HVAC off test. Here is a comparison of GDS CALIB STRAIN NOLINES from earlier on in this lock and during the test. I picked both times off the range plot from a time with no glitches.
Improvement from removal of 120 Hz jitter peak, apparent reduction of 52 Hz peak, and broadband noise reduction at low frequency (scatter noise?).
I have attached a second plot showing the low frequency (1-10 Hz) spectrum of OMC DCPD SUM, showing no appreciable change in the low frequency portion of DARM from this test.
Reminders from the summary pages as to why we got so much BNS range improvement from removing the 52 Hz and 120 Hz features shown in Elenna's ASD comparison. Pulled from https://ldas-jobs.ligo-wa.caltech.edu/~detchar/summary/day/20230817/lock/range/. Range integrand shows ~15 and ~5 MPC/rtHz reduction at the 52 and 120 Hz features. BNS range time series shows brief ~15 MPC improvement at 15:30 UTC during Robert's HVAC OFF tests.
Here is a spectrum of the MICH, PRCL, and SRCL error signals at the time of this test. The most visible change is the reduction of the 120 Hz jitter peak also seen in DARM. There might be some reduction in noisy peaks around 10-40 Hz in the signals, but the effect is small enough it would be useful to repeat this test to see if we can trust that improvement.
Note: the spectra have strange shapes, I think related to some whitening or calibration effect that I haven't bothered to think about to make these plots. I know we have properly calibrated versions of the LSC spectra somewhere, but I am not sure where. For now these serve as a relative comparison.
According to Robert's follow-up / debrief aLOG (LHO:72331) and the time-stamps in the bottom left corner of Elenna's DTT plots, she's is using the time 2023-08-17 15:27 UTC, and that corresponds to the time when Robert had turned off all four the supply fans (SF1, SF2, SF3, and SF4) in the corner station (CS) air handler units (AHU) 1 and 2 that supply the LVEA around 2023-08-17 15:26 UTC.
