Long lock from Patrick's shift roared through all of TJ's shift and most of my shift. Dropped out at 6:12am today (yesterday it was around 5:45am). Here is time info for the long lock:
I ran through a couple of alignments after the last lockloss, but they have not looked great, so handing off to the Day Crew (Jim covering for Cheryl who will be in soon).
Note: On my alignments, I mainly tweaked ETMy, PR3 (just a little), and then the BS.
In the SDF Overview medm, have only (3) channels which are RED during the current lock/Science Mode segment.
When we are happy with these changes, we should GREEN these channels up.
Once again, handed a nicely locked & in-Science-Mode H1 from TJ, with a range of 54Mpc. Have had a couple of glitches which dropped the range a bit in the last few minutes though. (as I am typing noticed the end of a huge glitch [~8:42:30-ish utc] which took the range down to 2Mpc! Nothing obvious for a reason why on any of the FOMs.)
Seismically, all is quiet on the LHO front with winds below 10mph.
Noticed that the CDS Overview (on video2) must have had an old medm up because when going through checksheet and checking this window I noticed H1CALCS had no purple EXC box (mentioned to Jeff and he was surprised). Then I noticed it was fine on my workstation. So medm restarted on video2.
[Time for caffeine.]
J. Kissel, K. Izumi, E. Hall for the CAL Team We've been studying the discrepancies between the GDS low-latency pipeline (which produces H1:GDS-CALIB_STRAIN) vs what comes out of the CAL-CS front-end real-time calibration (which produces H1:CAL-DELTAL_EXTERNAL_DQ). Please check out G1500750 for a discussion on this.
Following up this earlier report on pre-ER7 narrow lines in H1 DARM, attached is a corresponding list of early ER7 lines and some spectra for 30.5 hours of data from May 31 through June 4 at 13:00 UTC, based on FScans SFTs generated as of Thursday morning. Figure 1 shows the 0-2000 Hz spectrum for the early ER7 data with line labels according to the same scheme as before. Figure 2 shows the mid-May and early ER7 spectra overlain without line label clutter. Attachment 1 is the early ER7 line list (nearly identical in line frequencies but not strengths to that of mid-May) Attachment 2 is a zipped tar file of 27 sub-band spectra for early ER7 with lines labeled. Attachment 3 is a zipped tar file of 27 sub-band spectra comparing mid-May to early ER7 without labels. I haven't yet digested all of the changes from mid-May to the early ER7A data (what I call ER7A here), but here are things that are immediately apparent::
We used the coherence tool to try and see if there was a coherence between h(t) and other channels for this 36.9725 Hz noise line and its harmonics. There is a coherence between the h(t) channel and ... H1:PEM-CS_MAG_EBAY_SUSRACK_Z_DQ at 36.9725 Hz * 2 = 73.9450 Hz (definitely) 36.9725 Hz * 3 = 110.9175 Hz (barely above background) 36.9725 Hz * 4 = 147.89 Hz (definitely) 36.9725 Hz * 5 = 184.8625 Hz (above background) 36.9725 Hz * 6 = 221.8350 Hz (definitely) ... For whatever reason the even harmonics are stronger. The mat file for the coherence is here: https://ldas-jobs.ligo-wa.caltech.edu/~eric.coughlin/ER7/LineSearch/H1_COH_1116633616_1118275216_SHORT_1_webpage/data/H1:PEM-CS_MAG_EBAY_SUSRACK_Z_DQ_data.mat For H1:PEM-CS_MAG_EBAY_SUSRACK_X_DQ there is a coherence with h(t) at 36.9725 Hz * 4 = 147.89 Hz (barely about background) See https://ldas-jobs.ligo-wa.caltech.edu/~eric.coughlin/ER7/LineSearch/H1_COH_1116633616_1118275216_SHORT_1_webpage/data/H1:PEM-CS_MAG_EBAY_SUSRACK_X_DQ_data.mat For For H1:PEM-CS_MAG_EBAY_SUSRACK_Y_DQ there is a coherence with h(t) at 36.9725 Hz * 2 = 73.9450 Hz (barely above background) 36.9725 Hz * 4 = 147.89 Hz (above background) 36.9725 Hz * 5 = 184.8625 Hz (barely above background) 36.9725 Hz * 6 = 221.8350 Hz (above background) ... See https://ldas-jobs.ligo-wa.caltech.edu/~eric.coughlin/ER7/LineSearch/H1_COH_1116633616_1118275216_SHORT_1_webpage/data/H1:PEM-CS_MAG_EBAY_SUSRACK_Y_DQ_data.mat Nothing in the other magnetometers. Nelson, Eric Coughlin, Michael Coughlin
The MICH feedforward path into DARM has been retuned, since Gabriele recently found a nontrivial amount of coupling from 50 to 200 Hz.
First, the MICH → DARM and MICHFF → DARM paths were measured according to the prescription given here. Then the ratio of these TFs was vectfitted and loaded into FM4 of LSC-MICHFF. This is meant to stand in place of FM5, which is the old frequency-dependent compensation filter. The necessary feedforward gain has been absorbed into FM4, so the filter module gain should now be 1. These changes have been written into the LSC_FF state in the Guardian.
The attachment shows the performance of the new retuning compared to the old retuning. At the start of this exercise, I had already changed the FM gain of the "old" retuning from 0.038 (in the Guardian) to 0.045, as this removed a lot of the coherence near 100 Hz.
Also, I had previously widened the violin stopband in BS M2 L, but had not propagated this change to the analogous filter in LSC-MICHFF. This is now fixed. Also note that if any change is made to the invBS compensation filter in BS M3 L, this change must be propagated to LSC-MICHFF as well.
I did not have time to implement SRCL feedforward. I suspect it would be a quick job, and could be done parasitically with other tweaking activities.
Coherence between MICH and DARM before and after Evan's work. (As far as I can tell, yes, DARM got better and the range improved..although it is not evident from the SNSH channel, as it had problems around the time of Evan's work.) Let's see how much this coupling changes over time.
The LSC-MICHFF_TRAMP is now set to 3 versus the snap setting of 5 sec. This shows in the LSC SDF diff Table now and should be reverted or accepted, Evan?
Snap setting of 5 seconds is probably better.
I injected pitch (270 Hz) and yaw (280 Hz) lines with the PSL piezo mirror and then tried to minimize them in DARM by adjusting values of the offsets of DOF2P and DOF1Y of the IMC WFS. It was a bit tricky because of ten-minute alignment time scales. But we reduced the injected pitch peak height by a factor of 2, and the yaw by 5 (we cared most about yaw because the PSL jitter peaks are mainly in yaw). The inspiral range increased by a few Mpc and the jitter peaks seemed down by a factor of a few, but I will wait until tomorrow to put in spectra in order to be sure that the improvement is stable. DOF2P was changed from 135.9 to 350 and DOF1Y from 47.5 to 200. I think we could do better with another 2 hours.
Robert, Kiwamu, Evan
This change now shows in the ASCIMC SDF Table.
19:48 - Intent Bit set back to Undisturbed. Lock is still going strong.
16:00 - Took the chair with both H1 and L1 locked.
17:31 - L1 lost lock, so I turned the Intent Bit off for Evanand Robert to return LSC Feedfowardand tune WFS offsets.
This work should last about 2 hours.
Hannah Fair, Stefan Ballmer Just a few days ago the interferometer tended to loose lock at full input power (23W) in ~10 to 40min. (Hence the run is at 17.3W.) We went back to the following lock losses: 1) Jun 02 2015 01:49:44 UTC = GPS 1117245000 2) Jun 02 2015 03:53:19 UTC = GPS 1117252415 3) Jun 02 2015 08:13:04 UTC = GPS 1117268000 4) Jun 02 2015 11:33:54 UTC = GPS 1117280050 All of them showed as immediate cause of lockloss a run-away of the MICH_Y ASC loop on a time scale of about 0.2sec. (0Plots 1-4). However, lock losses 3) and 4) also showed a significant control signal drift in PRC2, SRC1, SRC2 (both Yaw and Pit) over about one minute time scale before the lock-loss. We therefore suggest lowering the MICH_Y ASC gain slightly next time we try 23W, and then investigate the ASC signals, most likely for the SRC.
Scott L. Ed P. Chris S. We found some cracks in the concrete enclosure while hanging lights this afternoon, 730 meters south of X-End. The cracks run the entire length of a single panel on both the east and west side of the tube, up approximately 2.1 and 2.3 meters respectively from the slab. Picture 018 also shows the crack extending >2" horizontally at the end of the panel. I have not ever put anything on resource space but I do have 20 more pictures that I will attempt to download there. Only 15 meters of tube cleaned today after moving lights and looking at the cracks.
Had trouble in the morning maintaining lock in the transition to REFL_TRANS. I was going to do an initial alignment per Sheila's suggestion, but then it locked. I have not done an alignment today. Ended the shift in science mode.
The computer video6 which was used to display the Range display and the ISC guardian overview has been replaced. The new computer is an Intel NUC, which is a 4 core i5 CPU, 16G RAM computer running Ubuntu 14.04, with a KDE display manager. The computer has a wireless keyboard which the operator manages. The hostname for the computer is nuc0. This computer cannot be managed with remote desktop at this time, only with the remote keyboard. Instructions for maintaining the displays on the computer are in the CDS wiki, under Operations/FiguresOfMerit.
[Daniel, Paul]
We have updated our LHO FINESSE file (https://dcc.ligo.org/LIGO-T1300904) to compute an estimate of the DCCP as requested by Jeff.
The DCCP value we calculated was 369 Hz. This is for a well mode matched and aligned setup.
The optics details were taken from the galaxy page for the various mirrors installed at LHO. We also tried to get some more accurate losses in the arms taken from the following documents:
| Optic | Loss [ppm] | LHO aLOG ref. |
| ITMX | 42 | N.A. |
| ETMX | 78 | 16082 |
| XARM | 120 | 16579 |
| ITMY | 30 | N.A. |
| ETMY | 125 | 15919 |
| YARM | 155 | 15937 |
The caveat here is that the DCCP value has been seen to wander depending on alignment, as was reproduced in some of Gabriele's simulations, https://dcc.ligo.org/LIGO-G1500641. Here Gabriele found a slightly higher well aligned DCCP value of ~380Hz. We know that the DDCP value depends on many variables (alignment, mode mismatch in SRC, arm losses etc.), some of which are not yet well constrained with measurements.
Attached is a plot of the DARM TF from the Finesse model, which is well described by a single pole at 369 Hz.
This is my own reckoning of the loss measurements we've performed after the ETMs were cleaned in December. Note that these visibility measurements do not independently measure losses from the ITMs or the ETMs; they just give the total arm loss from scatter and absorption.
If these measurements are not satisfactory, we could always repeat them.
We could also repeat the ringdown measurements, but we would need to be more careful when collecting the data. Last time, the incident IR power on the arm fluctuated from lock to lock, which made the uncertainties in the inferred losses much too big for the measurements to be usable.
| Loss | Date | Method | alog | Notes |
| 78(18) | 2015-01-14 | Visibility | 16082 | — |
| Loss | Date | Method | alog | Notes |
| 286(33) | 2015-01-05 | Visibility | 15874 | Green WFS not on |
| 125(19) | 2015-01-07 | Visibility | 15919 | — |
| 155(19) | 2015-01-08 | Visibility | 15937 | — |
| 140(16) | 2015-01-09 | Visibility | 15991 | — |
14:26 Starting beam tube washing at HNW-4-064 in ~ 10 minutes 15:11 Jim replacing video6 mac mini with NUC 15:49 Went to science mode 15:59 Beam tube washing is done for the day
Betsy, Pattrick, Dave
The local copy of H1SUSMC2.txt filter file was out of sync with the SVN repository. When we tried to commit it we got a "copy out of date" error. To get around this, we copied our version into a backup file, svn reverted the file, svn updated the file, copied back in our new version of the file and then were able to commit it to the repository. During this file shell game, the h1susmc2 front end computer saw the file change and flagged the CFC bit (reporting modified file). This is a latched bit, so even though we returned the file back to the original the flag persists. During the H1 down time, we loaded all coefficients on h1susmc2 to clear the flag. No change to filters were applied.
This appears to be from Evan opening awggui and selecting a channel. It showed up even though he never hit start. It went away when he closed awggui.
Since there have been a few uncommitted commissioning changes to filter files and guardian code, Dave and Sheila confirmed it was time to commit them all to the svn since the IFO is running ~well for E7. Dave and I are working to clear house in all subsystems. I have committed:
All SUS.txt filter files
All 2 ASC filter files - H1ASC.txt, H1ASCIMC.txt
All 2 ASC filter files -H1ALSEX.txt, H1ALSEY.txt
All LSC.py guardian scripts
Note, all SUS guardians are up-to-date in the SVN.
When we ent to commit H1SUSMC2 it failed with an error stating file is "out of date". So, we copied the file to a backup and did a work around:
betsy.bland@operator1:/opt/rtcds/userapps/release/sus/h1/filterfiles$ cp H1SUSMC2.txt H1SUSMC2.txtbak
betsy.bland@operator1:/opt/rtcds/userapps/release/sus/h1/filterfiles$ svn up H1SUSMC2.txt
Conflict discovered in 'H1SUSMC2.txt'.
Select: (p) postpone, (df) diff-full, (e) edit,
(mc) mine-conflict, (tc) theirs-conflict,
(s) show all options: ^Csvn: Caught signal
betsy.bland@operator1:/opt/rtcds/userapps/release/sus/h1/filterfiles$ svn revert H1SUSMC2.txt
Reverted 'H1SUSMC2.txt'
betsy.bland@operator1:/opt/rtcds/userapps/release/sus/h1/filterfiles$ svn up H1SUSMC2.txt
U H1SUSMC2.txt
Updated to revision 10745.
betsy.bland@operator1:/opt/rtcds/userapps/release/sus/h1/filterfiles$ cp H1SUSMC2.txtbak H1SUSMC2.txt
This however caused the FE DAQ status to show the error that the filter file had changed. Indeed to file changed name, and then back, but we confirm that the contents of the file are the same, so we will have to hit the LOAD COEFF button on MC2 to clear the FE alarm.
The IFO was down, so we hit the load coeff on MC2 during it's walk back up to LSC_FF lock. The IFO didn't waiver so all seems fine.