After Evan & Filiberto were out of LVEA relocked the IOF on the first attempt with no apparent problems. Ran the A2L script and cleared the SUS SDF notifications. Back to Observing mode at 20:40 (12:40) SDF notification are listed in the attached snapshots. NOTE: Still getting RF45 noise and ETMY saturations. Range is being adversely effected
The A2L script was updated yesterday to match the LLO script - the big change was having separate folders for the data for each site, so it's easier to tell which data is from where. The new folder didn't have write access from the Ops account though, so the A2L script was failing for Jeff. There are so many EPICS writes and messages during the script that the error message scrolled off the top of the terminal window before he saw it.
Anyhow, I have chmoded the directory, so it should be fine in the future, but also I have reverted to the P2L and Y2L values that we have been using for the last month or so, since it's not clear that the new values are okay (since the script had some errors part way through).
Not a generally good morning. IFO broke lock at 16:16 (08:16). After running initial alignment; relocked the IFO and went into Observing mode at 18:25 (10:25). Shortly after relocking started seeing a lot of RF45 noise events at a rate of several per minute. It was decided to have Evan & Filiberto to go into the LVEA to check the RF cabling. While Evan & Filiberto were in the LVEA working on the cabling, the IFO dropped lock. Waiting for them to come out before relocking.
RE lockloss at 8:16.
Bubba and I were turning on a few heaters and one of these feeds the output arm (HAM5-6).
The plots show duct temperature near the heater, zone temperature near the floor, and 10 days of zone temperatures.
I have multiplied the Observation_Ready bit by 70 to get it on the same scale as the temperature.
Coincidence?
Robert suggested that looking at the OpLevs could give an idea as to if this lockloss could be caused by the temperature. I trended the OpLevs and compared their motion with the LVEA temperatures, and there is definitely some correlation seen on the SR3 OpLev movements and the temp of the LVEA. You could probably make an argument for ITMY and PR3 OpLevs as well, but it is not as clear as the SR3.
So was this temperature excusion the cause of the lockloss? Well, the ASC signals didn't seem to be showing any signs of a problem before lockloss, seismic activity was low to minimal, winds low to minimal, and I didn't see any other obvious culprits.
I attached a trend of some of the CS OpLevs and LVEA temp in a 6 hour window, as well as a group of Lockloss plots with ASC signals and such.
If air temperature was a factor in this lockloss I would be suspicious of electronics outside the vacuum near HAM5 or 6. I would not expect in-vacuum hardware to respond so promptly.
[JeffB, Jenne]
After some closer looking, we don't think that the temperature was a direct cause of the locklosss. By the time the lock was lost, the temperature in FMC-ZONE4 had only changed by a few tenths of a degree - well within our regular diurnal temperature changes. About 16 seconds before the lockloss, SRC2 Pitch and Yaw both started walking away. I don't know why they started walking away, but there's probably nothing to so about this, other than eventually move the SRC ASC from AS36 to some other signal, as we're planning to do after O1 anyway.
After relocking this morning the RF45 noise has come back, at a rate of several time per minute. This is knocking the range down into the high teens and low 20s Mpc. Confer with Evan, Keita, Mike, Daniel, and Filiberto. Set the intent bit to Commissioning while Evan & Filiberto are in the LVEA checking cabling.
Fil and I went to the ISC rack and started tapping the 45 MHz cable that comes out of the patch panel. As noted before, this cable is extremely microphonic. Tapping on the coiled-up portion produces huge burps in the EOM driver control signal.
We added some extra velcro around the coil, and then fixed the coil to the rack with some zip ties.
However, now that we have relocked it seems that this does not improve the situation.
IFO broke lock at 16:16 (08:16). Cause at this time is unknown. During relocking could not move past DRMI_1F. Consulted with Kiwamu and decided to run an initial alignment. IFO was relocked at NLN at 17:47 (09:47). Ran A2L script. There were SDF notifications for both ETMs and ITMs. Could not find a SUS person, so took screenshots and accepted all. Set intent bit to Observing at 18:25. Spoke with Hugh about the BSC ST2 Guardian notifications.
Jeff - you've done the correct thing to accept these SDFs, so good. As Evan says in his 23085 alog, the violin damping buttons were all switched back ON (via gain) this time up in the Guardian. Also, everytime you run the A2L script we should eye-ball that the values are not crazy different and then accept them in SDF. Thanks!
Pursuant to a discussion on the PSL call this morning, I'm posting trends of the humidity and temperature in the Laser Room, Laser Diode Room, and Chiller Room over the past 365 days.
The humidity sensors are coupled with the temperature sensors. We have more temperature sensors, but we decided not to record their coupled humidity sensor signals.
Just for comparison's sake, a plot of the humidity sensor in the high power oscillator box is included.
See LLO alog, for comparable plots
Attached is a plot of the NPRO output power and the output power of the two pump diodes for the past 4 years. One can see that the diode current was increased around 8/16/2013 and 6/5/2014. The first increase in pump current was about 200 mA; the second about 50 mA. This NPRO is very close to its "maximum" diode current.
See LLO alog for comparison
O1 days 46,47
model restarts logged for Mon 02/Nov/2015 No restarts reported
model restarts logged for Tue 03/Nov/2015
2015_11_03 09:30 h1hpiitmy
2015_11_03 09:30 h1iopseib1
2015_11_03 09:30 h1isiitmy
2015_11_03 10:16 h1isibs
2015_11_03 10:18 h1isiitmx
2015_11_03 10:26 h1isietmx
2015_11_03 10:31 h1isietmy
Maintenance day. Power cycle of h1seib1, new BSC ISI models with reduced sensitivity to coil driver temp status bit when triggering watchdog.
Title: 11/04/2015, Day Shift 16:00 – 00:00 (08:00 – 16:00) All times in UTC (PT) State of H1: 16:00 (08:00), The IFO is locked at NOMINAL_LOW_NOISE, in Observing mode Outgoing Operator: Jim Quick Summary: IFO locked in Observing for the past 9 hours. Winds are calm to light (0 – 3mph), seismic activity is quiet; microseism is centered around 0.3 um/s. A
Apologizes for the late entry. Yesterday all site supply fans were lubricated per the quarterly schedule. We also took the maintenance period opportunity to change some extremely dirty air filters which are located in the supply fan areas.
TITLE: 11/03 Owl: 8:00-16:00 UTC STATE Of H1: Observing @ ~75 MPc. SHIFT SUMMARY: SUPPORT: ACTIVITY LOG: H1 was locked when I arrived, RF45 was acting up occasionally, though. Otherwise quiet shift. 15:00 UTC Started receiving CS temp notifications, Bubba notified/working on it.
This morning about 15:00 UTC, I got a couple notifications that temps were low in the LVEA. I let Bubba know, but he was already working on it. I haven't heard any notifications since, Bubba said he will keep an eye on it.
I have turned off the violin mode damping filters for IX and IY by zeroing their gains. Patrick accepted these into SDF so that we can go to observing.
This is meant to be temporary, i.e., for this one lock only.
The next time the interferometer comes into lock, the Guardian will turn on the normal violin mode damping settings. These settings will appear as SDF diffs (two on IX, and six on IY). These should be accepted into SDF.
We do not expect these modes to ring up during the course of the lock. However, if the mode height on the control room DARM spectrum around 500 Hz rises above 10−16 m/rtHz, the damping should be turned back on:
A screenshot of the nominal IY damping settings is attached (I didn't take one for IX).
ITMX:
ITMY
Thanks to Jeff, Patrick, and Jim for babysitting this.
The second lock (after the earthquake) lasted about 10 hours. Strangely, the ITM first harmonics (which range from 500 to 505 Hz) do not all seem to ring down.
An analysis of this data to measure Q of the fundamental modes for ITMX and ITMY violin modes is reported in 23331. The few modes that show an actual ringdown have a Q of about 0.3e9.
An analysis of this data to measure Q of the 2nd harmonics for ITMX and ITMY violin modes is reported in 23383.
Now that we've cleaned up all of our systematics from the DARM model and released the O1 version (see LHO aLOG 22056, I've updated the diagram that explains how the actuation path clock cycle delay is derived, and also shows that the current value of 7 [clock cycles] or 427.3 [us] that was recently installed at both sites (LHO aLOG 21788) still does a fine job at approximating the total delay between the inverse sensing and actuation chains.
A good diagram on the timing of a hardware injection through the DARM path: LLO aLOG 22361