TITLE: 04/23 Owl Shift: 07:00-15:00 UTC (00:00-08:00 PST), all times posted in UTC
STATE of H1: Observing at 106Mpc
OUTGOING OPERATOR: Corey
CURRENT ENVIRONMENT:
Wind: 8mph Gusts, 6mph 5min avg
Primary useism: 0.13 μm/s
Secondary useism: 0.17 μm/s
QUICK SUMMARY:
Everything humming along nominally.
Sharan Banagiri, Philippe Nguyen, Robert Schofield
We have used 17.25 out of the 15-20 hours, and we are mostly done with PEM injections, though there are a few loose ends to tie up.
We made acoustic injections at MY - we didn’t find any coupling but did find an accelerometer that needs replacing, we made big shaker injections at EX, looked inside HAM5 and 6, saw the very bright small angle scattering from the septum window, and narrowed at least one component of the 48 Hz peak to the vertex. We also make some site activities injections, finding that we seem more sensitive than for previous runs, so we may want to do some more site activity tests.
Times UTC:
19:00-19:45
23:30 – 1:40
2:41 – 3:49
4:36 – 5:04
5:57 – 6:53
TITLE: 04/22 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Commissioning
INCOMING OPERATOR: Ed
SHIFT SUMMARY:
Got some locking practice this shift (specifically with ALSx alignment, & ALSx polarization). Also rode thru a 6.6 EQ. :)
LOG:
Here are notes for transition to EARTHQUAKE state tonight. Took an overview screenshot of various windows when I transitioned (attachement #1). Here are the notes:
Tagging @DetChar and SEI for data in seismic's sensor correction configuration transition studies.
Finally recovered from a lockloss after about an hour. Wanted to avoid going through an Initial Alignment, but went through grief mainly during LOCKING_ARMS_GREEN. ALSx looked fine but it would break lock after a few seconds/min even with WFS engaged. Here were the details:
(Sheila, Corey)
While I was in the Mechanical Room doing FAMIS tasks and while PEM Injections were ongoing, the Squeezer Unlocked at 0:37utc (5:37pm)....it had been locked since 23:18utc. I didn't notice this until about 1:06utc & then asked Sheila to take a look. At 1:09 she requested SQZ_READY_IFO to close the Beam Diverter to preserve the lock...but it had been locked 30min...so she said this step might not have been necessary.
Then requested SQUEEZING, and we were back to squeezing at 1:10utc.
Summary: Taking the SQZ_MANAGER to SQUEEZING got us back.
Sheila mentioned that the squeezer unlocked due to the TTFFS, and also because OMC_TRANS_RF3_DEMOD_RFMON dropped down to -40 (it should be at -20). Sheila said she would like to try a fix to address this tomorrow after she thinks about it.
Sadly, I did not get to grab info from the Log, because we had a lockloss, sorry.
Oplevs look good (see attached) in pit & yaw and do not need to be centered.
DQ Shifter: Edgard Bonilla.
Fellow: Daniel Vander-Hyde.
Mentor: Beverly Berger.
Summary for the shift:
More information can be found at: DQShiftLHO20190415
Addressed TCS Chillers (17:34-17:45 PST)
NOTES:
Made it to NLN & handful of SDF diffs. Went through the diffs while PEM injections were going on.
1) H1:SUS-MC2_M1_DRIVEALIGN_L2L_SW1R was saved in a wrong state with this OFFSET "on".
(Note: Jenne gave guidance about this channel. It is avail to turn "on" if we are having trouble locking the IMC & want to give it a little bump to help locking. But we should remember to turn this "off" as soon as the IMC locks. So this must have been Accepted when it was accidentally left "on". Anyway, tonight this offset was in the correct "off" state, and had the diff, so we ACCEPTED. Jenne fixed this issue for the future by adding a line in ISC_LOCK to turn OFF this offset--I believe she said in the PREP_FOR_LOCKING state.)
2) ECAT PLC1 Had Diffs (SDF diffs screenshot #1 attached) Due to ALS Remote Motorized Polarization Controller (medm screenshot #2 attached)
Not really sure why we're monitoring these channels (i.e. the Paddle X, Y, & Z channels) because these channels change whenever we make remote polarization changes. So, I unmonitored these three channels.
3) SPM Diff for TRamp for ISI EY
For some reason the Stage 2 Rx & Ry TRamps were 0 and SPM had a set point of 5. Since this is benign, I changed the TRamps to 5, but this then gave us new SDF diffs---which I ACCEPTED.
As for the polarization controller: These channels should be monitored and updated when the polarization is adjusted. Keep in mind that when you turn the controller on, you loose the last value and have to restore it! Set them back to monitoring.
TITLE: 04/22 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Commissioning
OUTGOING OPERATOR: Jim
CURRENT ENVIRONMENT:
Wind: 18mph Gusts, 15mph 5min avg
Primary useism: 0.07 μm/s
Secondary useism: 0.19 μm/s
QUICK SUMMARY:
The percentage of light in the wrong polarization on the two end station ALS tables is measured by dividing the rejected light by the incident light. The incident light is measured with a ~5% beamsplitter. Unfortunately, this beamsplitter is itself polarization dependent, which can lead to apparent percentages above 100%! The attached plot shows these photodetectors as well as the reported percentages. If we assume that the transmitted light doesn't change as function of the selected polarization, the rejected light is in no instance higher than the incident light---even if the reported percentage is well above 100%.
Bottom line: The calculated percentages can only be believed near the correct polarization.
TITLE: 04/22 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Commissioning
INCOMING OPERATOR: Corey
SHIFT SUMMARY:
LOG:
18:00 Christina to Mids
18:15 Kyle to MX
18:45 Robert to MY for PEM injections
19:00 JeffB to LVEA
19:30 Kyle to MX
20:00 I went to EX to recenter BRSX
21:45 Start Initial alignment after a couple eqs in Canada
To track more precisely the variation of the detector noise during the science run, I wrote a simple code that computes the band-limited RMS of the calibrated strain in a bunch of bands. This is a first step toward finding correlation between the noise variation and auxiliary channels.
Instead of using a set of equally spaced bands, I looked at spectrum of GDS-CALIB_STRAIN and tried to select some bands that correspond to interesting regions and features. The plot below show the selected bands.
The algorithm resides on our GIT repository https://git.ligo.org/gabriele-vajente/blrms. So far it can query the segments database to select all times in ANALYSIS_READY and compute the BLRMS for all of them. The results are saved on disk and can be accessed at
https://ldas-jobs.ligo.caltech.edu/~gabriele.vajente/BLRMS_data/
See the README file for details. For each segment, there is a data file containing:
The time series consist of a BLRMS value every 2.5 seconds, computed with 5-seconds-long FFT and 50% overlap. Sometimes there are glitches in the data that makes it hard to interpreter what happens to the BLRMS. For this reason the code implements two ways to remove glitches
Some examples of the results in the plots below.
The first plot shows the BLRMS in the LHO band 44-56 Hz, which shows a little bump with amplitude that changes with time. There is also a line in this band, which is removed by the algorithm. The traces below show the effect of smoothing and glitch removal.
The second plot below shows the effect of line removal for the band 56-62 Hz, which is affected by a large 60 Hz.
Finally, the last plot shows the effect of the glitch removal algorithm, by zooming in on the time axis:
Unlike the low (but not zero) coherence I found on 3/25, on 3/28 and today, 4/22, there are conferences in the IMs in yaw and Cal Delta of almost 0.4. I added IM4 Trans and ISS Second Loop, and they have conferences with Cal Delta between 0.3 and 0.6. My alog from 3/25 did not find this level of coherence with IMs, alog 47845.
I took an average over spectras of 1800 s from before the calibration lines were moved and reduced and after this was done (noted here: https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=48534 and https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=48578).
The first two plots show a comparison over 20 to 100 Hz. 4 lines at 51, 51.8 Hz, ... (a comb of 0.8 Hz spacing) have disappeared, although I'm not sure this is related to the changes in the calibration lines. The three lines at 2*35.9, 2*36.7 and 35.6+36.7 Hz have also disappeared. As discussed in https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=48161 and https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=48357, if those three lines were really harmonics of those calibration lines it makes sense that they are gone since these lines have been moved. New lines have appeared, for example at 35.2 = 2*17.6 Hz, which could be linked to the new calibration line frequencies.
The two last plots show the range between 300 and 400 Hz. Not only the 331.9 Hz line has disappeared since it has been moved, also sidebands at 315.2 = 331.9 - 16.7 Hz, 348.6 = 331.9 + 15.9 Hz are gone.
TITLE: 04/22 Owl Shift: 07:00-15:00 UTC (00:00-08:00 PST), all times posted in UTC
STATE of H1: Observing at 109Mpc
INCOMING OPERATOR: Jim
SHIFT SUMMARY:
Quiet night overall. 12hrs locked/11 hours Observing.
LOG:
Philippe Nguyen, Robert Schofield
We made a shaker injection at the corner station and several impulse injections at EY.
Also, I manipulated the HVAC. This was done during observation mode, as in the past, since we don't drop observing for automatic and other usual HVAC changes. The figure shows that the HVAC is costing us 3 or 4 MPc. I then did a bunch of manipulations to narrow down the source. The dominant problem seems to be AHU 1,2 and 3, and, to a lesser extend, the turbines at the end stations. These are all running at higher rates than they were during O2. I will try do some further manipulations tomorrow to determine how much range we could get by going back to normal flows (my understanding is that they were increased for improved temperature control, I believe during the winter).
Here is the list of manipulations :
Switching all off. Begin: 16:35; All off: 16:44
Switching all back on. Begin 16:59; All on 17:10
Switching all off: Begin 17: 22; All off: 17:33
Switching all back on: Begin 17:48; All on: 17:57
Switching all off: Begin: 18:14; All off: 18:25
Switching all on: Begin 18:44; All on: 19:06
Switching off EY. Begin: 19:31; EY off: 19:39
Switching EY back on. Begin: 19:49; on: 19:55
Switching off CS AHU-3. Begin: 19:54; AHU-3 off: 19:55
Switching on CS AHU-3 and turning off CS AHU-1&2. Begin 22:02; Complete: 22:03
Switching off CS chiller. Begin 20:13; off: 20:20
Switching on CS AUH-1&2 and chiller AND switching off EX. Begin: 20:25; Complete: 20:35
Switching on EX. Begin: 20:49; End: 20:51
Switching EX off. Begin: 21:06; All off: 21:15
Switching EX back on. Begin: 21:30; All on: 21:45
Switching CS AHU4 (office area) off. Begin: 21:57 Off: 21:58
Switching CS AHU4 ON and turning EX off. Begin: 22:06; Complete: 22:15
Switching EX on. Start: 22:31; EX on: 22:33
Switching CS AHU1,2,3, chiller off. Start: 22:50; Complete: 22:59
Switching CS back on: 23:07
A correction: the corner station AHU 1,2 are not running at higher flows than they have been historically, while AHU 3 and the end stations are. This means there will be less to gain, so we didnt get back to shutting down on Sunday. Nevertheless, there could be some gain by dropping the EY and EX flow rates from about 11k CFM to between 8 and 9k CFM, and AHU3 down to about 6 per 5 & 6 from about 7k CFM per fan to about 6k CFM. Hopefully I will get a chance to try this.
Craig, Danny, Georgia
Today we stepped the SR3 heater down in 0.5 W steps, from 5W to 3.5W, according to plan. Here's what we found as we reduced the heating on SR3:
These values are shown in the first attachment, The kick in many signals just before we stepped down to 3.5 W is explained below.
We also monitored the DARM plant, frequency noise coupling, intensity noise coupling, and RF9 RIN coupling at each step.
While we were sitting at 4W on the SR3 heater we checked for detuning in the SRC ASC. This is the big peak in RF18 and RF90 in the first attachment; the 4th attachment is zoomed in during this time. We opened the loops and moved the sliders (top right plots), found nothing too interesting in pitch, but while aligning yaw we saw:
We were surprised that the optical gain increased, that doesn't seem to hang together with the other pieces of information here. Maybe we should consider operating with 4W on the SR3 heater, and re-phasing the SRC ASC for this. [Edit: notes for attachment 4: at t = -4500s we turned the SRC ASC back on, which is why the alignment went back to its nominal level. The calibration lines were off before t = -4800s, and the calibration values before this time are not to be trusted.)
We now understand that the increasing Kappa_C corresponded to a decrease in optical gain. So we were misaligning the SRC when we were aligning it by hand. The fact that RF18 was able to be improved with a misaligned SRC suggests there's room for improvement in the beamsplitter or PRC alignment.
We have made some DARM spectra from times during our SR3 heater test, and SRC alignment test.
First attachment shows DARM with the SR3 heater at 5W (black) compared to 4W (cyan), showing definite improvement in the bucket, which explains our range increase. A similar spectrum at 3.5 W on the SR3 heater sits somewhere in between these two.
Second attachment shows DARM with SR3 heater at 4W, with the normal alignment (blue), and when we opened the SRC ASC loops and "aligned" by hand, maximising POPAIR_B_RF18 (yellow). It seems like I can undo the SR3 heater improvement by misaligning the SRC...
The DARM plant did not change very much over the period of the SR3 heater move.
I measured the DARM plant 4 times, at SR3 power of 5W, 4.5W, 4W, and 3.5W. The DARM plant did not change very much this time.
According to some MCMC fits:
Optical Gain = 3.20 +- .28 × 106 cts/m (<0.8 % uncertainty)
DARM pole = 417.80 +- 15 Hz (4 % uncertainty)
Delay = 5.31 +- 1.7 × 10-5 s (33 % uncertainty)
Spring Freq = -5.12 +- 1.6 Hz (32 % uncertainty)
Spring Q = 37.11 +- 4.7 (13 % uncertainty)
This is a different result than the SR3 heater move at 30W input power. We moved the SR3 heater by less this time (from 5W to 3.5W rather than from 0 to 5 W before). We would also like to test the DARM plant for SRCL offset and DARM offset changes.
Also the frequency noise coupling to DARM did not change. Will post plots later once they are correct.
Posted DARM ASDs, calibrated frequency ASDs, and frequency coupling TF plots. DARM calibration: 6 zeros at 30 Hz, 6 poles at 0.3 Hz, gain of 1 Frequency Calibrations: Same as 46864. See attached freqCals.txt. Comparison to 30 W coupling: 45831. Before, we had a dip in the freq-to-DARM coupling at around 30 Hz where the radiation pressure and contrast defect effects destructively interfered. Now that effect seems to have flattened out. (Plot 3 in the PDF) Over the SR3 heater test cooling from 5W to 3.5W, it seems our freq-to-DARM coupling increases by a few percent, but does not change too radically.
Sheila was thinking the SR3 heater improvement could be attributed to the changing MICH and SRCL feed forward. I had a look at the coherence between DARM and MICH/PRCL/SRCL during the SR3 heater test, comparing a time at 5W (black) and a time at 4W (cyan), and am not convinced the coupling changed significantly. If anything the MICH coherence is worse at 4W than 5W in our frequency band of interest (20-60 Hz).
