TITLE: 11/14 OWL Shift: 00:00-08:00UTC (16:00-00:00PDT), all times posted in UTC
STATE of H1: High winds continue (now averaging about 30mph). LVEA useism is at 1.0um/s. For locking, we need winds below 20mph and useism down to 0.7um/s.
Incoming Operator: Cheryl Monitoring From Home
Support: Talked with Mike on the phone. Nutsinee was also here.
Quick Summary:
Shift was awash, with no locking attempts at all due to high seismic activity which has been going on 24+hrs! I have occupied an FOM screen (nuc0 & it can be view here) so Cheryl can monitor seismicity & ALS locking from home. If the winds ever calm down during her shift, she will come in.
Activities:
The first image attached is before the alignment work. The second image is after the alignment this afternoon (not quite there yet but looks much better) and the third image is the return beam with Hartmann plate on. The problem I ran into is that the return sled beam didn't seem to follow the path of the green light (I lost the return beam when I aligned green to the irises).
Another episode of RF45 glitches came back 5 hours ago (Nov14 00:36 UTC) and still on going.
Alastair, Corey, Nutsinee
First RTD/IR sens. alarm went red on the medm screen. A visual inspection at the controller box showed IR FAULT alarm which couldn't be untripped by simply turn the key back and forth. Before going out to swap the IR sensor box I discovered that the laser had actually stopped working almost two hours before the alarm went off. Meaning, nothing was heating up the viewport at the time IR sensor tripped. We followed Alastair's suggestion (with a permission from Mike) and inspected the viewport from inside the table anyway to make sure there's nothing obvious (eg. bug crawed in and got zapped). While taking down the IR sensor box the sensor happened to untripped itself. So we swapped the DB9 cable and plug it to the spare IR box and left it on the chassis. After the IR fault got untripped we were able to restart the laser.
The cause of CO2X tripped is unclear. There was a sharp drop in power supply but only by a tiny amount (-0.005 V) at the same time that the laser output power, laser temperature, and the current drawn dropped to 0. All these happened almost two hours before IR FAULT alarm went off. The chiller was working fine.
Is the IR sensor output available to be plotted? Along with an output of a nearby temperature sensor? The comparator circuit in the IR sensor may have tripped due to a local rise in temperature, or an instability in its power supply voltages.
Unfortunately I don't think there's a channel that allow us to monitor the IR sensor readout. If the comparator box were to trip due to a local rise in temperature it should have happened sooner since the box has never been moved since we installed it.
NOISY SEISMIC: This shift continues to have elevated wind (averaging about 25mph) and useism (Corner Station hovering at 1um/s). Attached are screen shots of the useism, and the wind for the last 24hrs. One can view the useism band here.
TCSX LASER BACK: Nutsinee brought the TCSX laser back & that will probably take something on the order of an hour(s) to heat up ITMx.
INITIAL ALIGNMENT NOT POSSIBLE YET: Also tried starting an initial alignment. I was able to get the arms to lock up (Y-arm looked good & X-arm needed some ETMx tweaking), but they only stay locked on the order of seconds and then get bumped around by the wind and drop. So this will make Initial Alignment tough: Still too noisy for the arms.
I have all BSC ISIs on 45mHz Blends.
We can still hear the building creaking & swaying in the wind. :-/
This is a continuation of the results reported in 23331 adding this time the Q measurements for the 2nd Harmonic of the violin modes for ITMX and ITMY suspensions. Based on the 10 hours of data from (UTC) 2015-11-04 06:35:00 to (UTC) 2015-11-04 16:15:00 when the damping filters for these harmonics were turned off.
I attach the spectrum of the 10 hours of data with resolution of 1mHz and 68 averages, in red are the peak frequencies identified here as 2nd harmonics for ITMX and ITMY and these are the ones I track here with a line tracker (iWave).
Attached are the summary plots for the line tracker locked modes; at the top is the frequency as a function of time and at the bottom is the Log of the amplitude as a function of time. A first order polynomial is fitted to Log(Amp) in order to obtain the Q of that mode.
In comparison with n 23331 this time we observe many more modes with a clear ringdown allowing for more accurate measurements of Q as shown next:
Frequency Q Delta_Q
1.0e+09 *
0.000000991746043 0.638343205424020 0.000149585967453
0.000000991932780 0.988513060431184 0.000433659978759
0.000000992424650 0 0
0.000000992793647 1.544250594114285 0.000442769972986
0.000000994277692 1.846260247611300 0.000357683597242
0.000000994646171 1.429803598985770 0.001138277433661
0.000000994733913 0 0
0.000000994897934 1.363257521653677 0.000632572972344
0.000000995365554 1.412623504284980 0.001169331947625
0.000000995645184 1.427802427814187 0.000897711718659
0.000000996250457 0 0
0.000000996528556 1.051941151626503 0.000247088823712
0.000000997717925 0 0
0.000000997887934 1.367480640577778 0.000256968037986
0.000000998664500 0 0
0.000000998805575 1.414837156915169 0.000225767863446
useism is still hight 0.5-1.0 um/s & winds are still averaging over 20mph.
TCSX laser tripped this evening as well. Nutsinee has been talking with Alastair & Mike about this. I am going to go out on the floor with her as her "buddy" as she inspects and does work on table. With this laser off, it takes an hour or two for the TCS to heat up ITMX once we get it back... so we'll be down for a while due to this (but we were already down due to obvious environmental issues.
While checking doors and turning off lights, I went ahead and topped off the Chiller. I put in 170mL (NOTE: Jeff topped it off yesterday to 250mL).
TITLE: 11/13 OWL Shift: 00:00-08:00UTC (16:00-00:00PDT), all times posted in UTC
STATE of H1: H1 is DOWN due to elevated winds & useism since last night's OWL shift.
Outgoing Operator: TJ
Support:
Quick Summary:
Gusts up to 50+mph. useism hovering around 0.7 um/s (must be atleast 0.5 to even think about locking...and this isn't even factoring wind.); useism has been at this value or higher for the last 22hrs!
While we are down, Nutsinee is doing Hartman Wavefront Sensor alignment out on the floor (TJ mentioned Landry approved this earlier). I see that HAM2, HAM5, & HAM6 ISIs are in the DAMPED state. Will transition back to ISOLATED when Nutsinee work complete.
TITLE: 11/13 DAY Shift: 16:00-00:00UTC (08:00-16:00 PDT), all times posted in UTC"
STATE Of H1: Down due to high wind, high useism, earthquake
SHIFT SUMMARY: Down the whole time, the winds and seismic activity keeping us down
INCOMING OPERATOR: Corey
ACTIVITY LOG:
I managed to get an initial alignment done when the winds were around 30mph, though it probably isn't a very good alignment because I could not let the WFS wait to converge too long or it would get knocked out of lock. After the IA, the winds have picked up to gusts of 50mph according to our Striptool. Keeping ALS locked is proving impossible.
The good news: useism may be trending down slightly. Maybe it's just an illusion from DMT, but I'd rather be optimistic.
Now we are getting gusts into the 60's. I even saw one 70mph gust.
model restarts logged for Thu 12/Nov/2015 No restarts reported
model restarts logged for Wed 11/Nov/2015 No restarts reported
Wanted to post some screenshots to show what we have going on.
1st attachment - Wind Striptool
2nd - NOAA Wave height
3rd - Seismic DMT in control room
Thanks for posting those - I was looking at wave heights earlier this morning and noticed the >10M waves off of British Columbia.
GWINC quantum noise curve is replaced with dynamically-generated shot noise curve. Radiation pressure will be included later.
The null stream spectrum shows 8×10−8 mA/rtHz shot noise, which seems to imply 17 mA of dc photocurrent on the sum, rather than the expected 20 mA.
Matt, Evan
The attachment shows two simple power-law curves (1/f2 and 1/f2.5) superimposed by eye on the residual. At first glance it is not clear which fits better.
In the case of 1/f2, we are looking for something that makes a white force noise on the bottom stage of a suspension (e.g., white electronics noise).
In the case of 1/f2.5, we are potentially looking at something less mundane; e.g., a force noise that goes like 1/f0.5, or potentially elevated structural loss on some suspension.
I took a quick look at the swept sine measurements Chris made earlier today, in order to derive a transfer function from H1:CAL-INJ_CW_OUT to H1:GDS-CALIB_STRAIN, using the same matlab script written recently to analyze L1 measurements>. Attached are spectrograms of H1:CAL-INJ_CW_OUT and H1:GDS-CALIB_STRAIN for the period of the measurements, along with the derived transfer function (see LLO alog entry above for explanation of graphs). Although there is an odd bump in magnitude response at 610 Hz (due to compensating for a notch at a BS 2nd violin harmonic?), things are otherwise smooth between 200 and 1400 Hz, albeit with phase wrapping at a bit more than 1000 Hz. This measurement seems at odds with Matt Pitkin's CW hardware injections recoveries (summary plot attached), as is the case for the recent L1 measurements. On the one hand, one could wonder if perhaps the swept sine just isn't sampling the frequency range finely enough to catch everything that affects the particular frequencies where CW injections are made, especially given the complexity of the inverse actuation filter Jeff posted here. On the other hand, the swept sine points were chosen to coincide almost exactly with CW injection frequencies (575 and 849 Hz) for which discrepancies between injection recovery and the transfer function measurements seem to occur. Matt has double-checked and triple-checked the phase definitions he uses in injection recovery. So the discrepancies in phase for pulsar 1 and 2 phase remain mysteries (for both H1 and L1). As discussed elsewhere, these lingering discrepancies suggest (to me, anyway) that we should simplify CW injections either by using PCAL with its considerably simpler IAF or by dispensing entirely with an IAF in the current ESD injection mode (i.e., rescale each CW injection amplitude by the point value of the inverse of the measured actuation function). Figure 1 - Spectrogram of H1:CAL-INJ_CW_OUT Figure 2 - Spectrogram of H1:GDS-CALIB_STRAIN Figure 3 - Derived transfer function from H1:CAL-INJ_CW_OUT tp H1:GDS-CALIB_STRAIN Figure 4 - Summary of CW hardware injection recoveries
It occurred to me belatedly that looking at the intermediate injection channel H1:CAL-INJ_HARDWARE_OUT might yield some insight into the above transfer structure in the 500-1000 Hz range, where it's hard to reconcile the measurements with CW hardware injections. Figure 1 shows the spectrogram during the sweep sine for the channel. Figure 2 shows the derived transfer function from CW_OUT to HARDWARE_OUT, which should follow the shape of the inverse actuation filter. Figure 3 shows the transfer function from HARDWARE_OUT to CALIB_STRAIN. More detailed information on all three transfer function measurements can be found on these web pages: H1:CAL-INJ_CW_OUT --> H1:CAL-INJ_HARDWARE_OUT H1:CAL-INJ_HARDWARE_OUT --> H1:GDS-CALIB_STRAIN H1:CAL-INJ_CW_OUT --> H!:GDS-CALIB_STRAIN Bottom line: there is non-trivial structure in the 500-1000 Hz band that the swept sine may not be capturing adequately to allow reliable comparison with injection recoveries. Bottom bottom line: it's time to try moving CW injections to PCAL with its simpler inverse actuation filter, as tentatively decided at yesterday's injections team telecon.
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.
Winds had died down - and were showing max. of about 22mph on site - now climbing back up.
Current winds around the Hanford site are mostly avergaes around 14mph and max. winds of 20-26mph, except for one station that says max. inds of 32mph, which is the highest I could find.
Y arm looks like it's been locked for an hour.
Since Y arm looks good and winds are still less than an hour ago, I'm heading to the site and will try to make progress on aligning and locking.