P. King, J. Oberling

Short Version:  The PSL is now up and running following the HPO water leak (first reported here, repairs reported here).

Long Version:  This morning, after giving the HPO ~48 hours to completely dry, we inspected the HPO optical surfaces.  The only thing found was some water spots on the head 1 4f lens (this was drag wiped clean); all other optical surfaces look good.  We then slowly brought up each head individually to ensure no contamination was causing the optical surfaces to glow; all good here as well.  The HPO was then successfully powered up an allowed to warm up for several minutes.  The front end came on without issue and the injection locking locked immediately.  After allowing the system to warm up for ~1 hour, I attempted to lock the PSL subsystems (PMC, FSS, ISS).  The PMC did not want to lock; according to Peter this was likely due to a slight horizontal misalignment (this is seen in a trend of the QPD that lives in the ISS box.  I unfortunately don't have a copy of it).  I returned to the enclosure and tweaked the beam alignment into the PMC and it locked without issue.  I then tweaked the PMC alignment further to maximize the power throughput.  PMC now has a visibility of ~80% with ~122W transmitted (with ISS on).  The FSS and ISS both locked without issue.  The PSL is now operational and fully recovered from the water leak.

The RTD module in the Beckhoff Link chassis what replaced this morning.  This module was showing problems since installation and was low on the list for replacement.  This morning we took advantage of PSL outage to take down the end station Beckhoff chassis to swap out this module. (EL3202)
The glitching is gone.

Last week HAM6's vacuum gauges were upgraded from the original pirani-coldcathode pair to the new Beckhoff Infinicon BPG-402. The new gauge has two channels (MOD1 and MOD2) which both record the vacuum over the full range of atmospheric (760 Torr) down to 1.e-09 Torr

I have renamed the archived Cold-Cathode minute trend files to match the new MOD1 name. In other words, if you ask for minute trend data prior to 8/10 for channel H0:VAC-LX_Y0_PT110_MOD1_PRESS_TORR you will be given data for the CC channel H0:VAC-LX_Y0_PT110B_PRESS_TORR. Note the archvied Pirani data is not accessible from NDS. I will write code to obtain data directly from the raw minute trend files if this is needed.

I will make the same changes for the other gauges which have been upgraded (PT170 and PT180)

Peter, Dave:

we modified h1pslfss under WP6100 to fix two bugs:

temperature channel inputs to DINCO for OOL and Ambient were swapped in the model

DINCO DAC outputs drive chans 08-11 and not 12-15

model was restarted, no DAQ restart was required.

Kyle, Chandra

Valved in IP and valved out TP. Pressure fell from 1.1e-6 Torr to 9e-7 Torr when IP was valved in and now is slowly rising with TP valved out (currently at 1.2e-6 Torr). After IP reaches thermal equilibrium we expect pressure to fall again. After that is observed we will shut down turbo + scroll (hopefully this afternoon).

Note: verified the MPC controller was ON and programmed for 500 L/s pump prior to valving back in. Read -5700 V. Now reads -5000 V with load.

LLO site was generally unaffected by the major flooding in Livingston and Baton Rouge area.

However, access to the site was difficult and hazardous so the site was closed Friday thru Wednesday.

Many staff had their homes inundated with river flood water.

All staff and visitors were either directly or indirectly affected by this event and many are still helping with the clean up and the recovery efforts underway.

The site is now fully open and has returned to regular operation.

Thanks to all of the LIGO family who have reached out to help those in need.

Note: The monthly Science Saturday event scheduled for tomorrow (08/20/2016) has been canceled.

Manual temp control via multiple variacs -> 10% decrease every few hours

SEI - progress made to miigate tripping of HAM6 ISI when fast shutter is activated

SUS -  no report

CDS - hopeful to close out gust meter work today; PEM AA chassis repaired; TCS AA chassis repaired. Both AA chassis suffered buffer chip damage most likely due to 'hot-swapping'.

CDS SW - continuing worl to address Frame Writer instability issues. Also, formulate a plan for '02

PSL - water leak is repaired. Optics have been wiped. Further inspection of collateral water issues will be performed. Power up of LASER hopeful for this afternoon. TCSY is back up and fully functional at full power. No hard evidence of BS OpLev glitching noted. If said glitchiness persists there will be a plan to swap out the laser.

VAC - will transition HAM6 to ION pump. RGA bakeout work between HAMs 4 and 5 will continue into tomorrow. Length of time most likely will depend on commissioners being able to return to their tasks.

FAC - Bubba will inish eyewash station inspections. DI skid will be re-plumbed'

• PSL still down

Attached is a plot of the cooling water flow rate for the 4 laser heads after replacement of the
burst hose (over head 3) and replacement of the head 4 flow sensor.  Also attached is a 30-day
trend plot of the same signals.  The large jump in flow rates about 6 days into the plot coincides
with replacement of the water manifold located under the table.

    At this stage it is too early to tell if replacing the head 4 flow sensor fixes the problem
with the all over the place signal seen in the 30-day trend plot.

Evan G., Jeff K.

Summary:
We measured the transfer functions of the OMC DCPD anti-aliasing (AA) module paths of ch13-16 for chassis S1102788. We measure this because the filter board was modified for these channels (LHO aLOG 28010). This is similar to the measurement Kiwamu made in LHO aLOG 21123. The OMC DCPD AA channels are 13 and 14 for DCPD A and B, respectively. The OMC PI AA channels are 15 and 16. We find that the notch behaviour of channel 13 matches what Kiwamu found in LHO aLOG 21123, but the notch of channel 14 is distorted (broken?). Channels 15 and 16 do not have the same notch behaviour (as to be expected for the PI paths, matching LHO aLOG 28085). These differences--compared to the calibration model reference AA filter--are below 1% in magnitude and less than 1 degree in phase below 7 kHz. While the calibration group is unaffected by the broken channel 14, noise from 65 kHz will be aliased down into the detection band. We should consider fixing this.

Details:
The setup for the measurements is shown in the first attachment, and the reference measurement (to remove the gain of the single ended to differential box) is shown in attachment 2. Each transfer function measurement is normalized by the reference measurement transfer function.

Data is saved in /ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/O2/H1/Measurements/OMCAAChassis

Analysis script is saved as /ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/O2/H1/Measurements/OMCAAChassis/process_aachassis_data_20160818.m

Plots are shown in the third attachment. Of particular note is to compare the new measurements to the AA filter model. Channel 14 (OMC DCPD B) now has a different behaviour near the notch. The difference is below 1% in magnitude and 1 degree in phase below 7 kHz, and does not force a revision in the calibration model reference AA filter.

I have updated the Beckhoff SDF system to the latest channel lists. I'll automate this process soon, here is the process I followed (using ecatc1plc1 as an example)

It is assumed that the /opt/rtcds/userapps/release/ecat area is up to date with its req files (which may be in DOS format)

First get the latest autoBurt.req into the ECAT target area:

cd /opt/rtcds/lho/h1/target/h1ecatc1/h1ecatc1plc1epics

cp autoBurt.req archive/autoBurt.req.18aug2016

cp /opt/rtcds/userapps/release/ecat/h1ecatc1/H1ECATC1_PLC1.req autoBurt.req

dos2unix autoBurt.req

Now get this autoBurt into the Beckhoff-SDF target area and use it to generate the new monitor.req file

cd /opt/rtcds/lho/h1/target/h1sysecatc1plc1sdf/h1sysecatc1plc1sdfepics

cp autoBurt.req archive/autoBurt.req.18aug2016

cp ../../h1ecatc1/h1ecatc1plc1epics/autoBurt.req .

cd burt

cp monitor.req archive/monitor.req.18aug2016

grep "^H" ../autoBurt.req | sort > monitor.req

Now restart the SDF target on h1build (as user controls)

h1sysecatc1plc1sdfstartup

If channels have been added, open the SDF MEDM screen and view the 'CHANS NOT INIT' table. Press the global 'MON' button (which selects all channels to ACCEPT and MON) and 'CONFIRM'. Now all new channels are being monitored, commissioners can decide if any should be taken out of this list.

Finally check the snap file changes into SVN.

This week I installed the ISS Outer Loop chassis into H1-PSL-R1, and hooked most of its cables up.  The two AA cables for PDs 5-8 are not hooked up to an AA Chassis yet, and will be hooked up once the original servo is removed from the AA Chassis (The intention is to re-use one of the original ISS Outer loop servo's cables.)  With the PSL down, I was unable to do any system testing.  I have not disconnected any cables from the original servo, so it is still fully functional.  I made an medm screen in UserApps/psl/h1/medm/H1PSL_ISS_OL.adl  All of the new servo's functionality seems to be working.

The TCS system had a bad channel that I traced back to the AA Chassis, S1301168.  It turns out that 2 of the input buffers (U2 on channels 11 and 12) were bad.  I replaced them, and now everything works fine.  In the e-traveller, it seems that these chips have been replaced once before in February, 2015.  We should keep an eye on them.

The broken hose was replaced.  An attached picture shows the burst end of the hose and the fitting that
goes over that end.  The two other attached pictures shows the hose, end on.

    The turbine flow sensor for head 4 was replaced.  Whilst there was no problem with this sensor per
se, its output was somewhat noisier than the three other sensors.  Replacing it now seemed like a prudent
thing to do.  A visual inspection of the flow sensor showed what might be a small build up of material
around the turbine.  If true that would in part explain the noisy signal from this sensor.

    The bulge in the crystal chiller return leg hose section in the chiller room was removed.

    The resonator optics of the high power oscillator were inspected for dust and water marks.  The 4f
lenses for heads 3 and 4 were drag wiped.  The lens in front of the reverse direction power monitoring
photodiode was drag wiped clean.  The fibre bundle ends are being given more time to dry out.




JeffB / Peter

I have been taking spectra from the SR785 (WP6005) whenever I get a chance over the last week to see if there is any evidence of three mode interactions in the 60kHz to 70kHz region that we will not be sensitive to with the aliased OMC DCPD HF channels that we normally analyze.
There is a consistent peak at 62935Hz, this peak is present with no optical power in the arm cavities.
There are several other more transient peaks, one of the times several had large amplitudes is shown in the first figure.
The largest peak is at 63776Hz  The maximum amplitude seen was 5E-6  This is about the same as the 18040Hz mode when it is 2 orders of magnitude above thermal noise and 2 orders of magnitude under unlocking the cavity.
The second largest is at 70160Hz and the third largest at 62336.

There is no evidence of peaks in DARM at this time at the expected aliased frequencies 1760Hz,  3200Hz or 4624Hz and the peaks that appear in the HF channels that do not appear in the normal DCPD channels do not coincide in frequency, see the second image.

Summary:

The high freqency calibration lines injected at the end of O1 (alog 24843) were analyzed to estimate the sensing function at those frequencies and compare it to the matlab DARM model. The calibration at frequencies above few kHz shows deviation from the model. The upward trend in the residual, as shown in the plot below, looks like the effect of the bulk elastic deformation of the testmass due to the misalignment of the pcal beams. However, this is not a definitive conclusion because the phase doesnot seems to suffer so much and also the error bars are too large to make a definitive statement. A set of measurement might be necessary to see if this effect is in fact reproducible.

Details:

The SLM tool was used to estimate the line amplitude with FFT duration listed below for each individual lines. The mean of the several data points was taken as the central value and the coherence of the measurement was estimated using magnitude squared coherence:

Coh = (A.B*)² / A² * B²

where A  and B are amplitude of DARM_ERR and PCAL_PD channels readout.

Freq    Amplitude    Start Time           Stop Time        Duration     FFT       Data points   Optical Gain
(Hz)           (ct)        (mm-dd UTC)     (mm-dd UTC)    (hh:mm)    (mins)      (#'s)             (kappa_C)
------------------------------------------------------------------------------------------------------------------------------------------
1001.3       35k         01-09 22:45     01-10 00:05         01:20         10           8                   0.995 

1501.3       35k         01-09 21:12     01-09 22:42         01:30         10           9                   0.995

2001.3       35k         01-09 18:38     01-09 21:03        02:25          10          13                  1.00

2501.3       40k         01-09 12:13     01-09 18:31        06:18          30          12                  0.995
 
3001.3       35k         01-10 00:09     01-10 04:38        04:29          30           8                   0.99-0.96 (Fluctuating)

3501.3       35k         01-10 04:41     01-10 12:07        05:26          30          10                  0.99               

4001.3       40k         01-09 04:11     01-09 12:04        07:55          60           5                   1.00

4501.3       40k         01-10 17:38     01-11 06:02        12:24          60          11                   0.99

5001.3       40k         01-11 06:18     01-11 15:00        ~9:00          60           9                    -----

These additional data points were added to one of the Pcal sweep done earlier during the run. In this case I picked the data from 2015-10-28. The optical gain during this sweep measurement was around 0.985 compared to 0.99-1.00 (from table above) during the high frequency injections. These optical gains were eye-balled from the detchar summary pages so I considered them within the margin of error and thus didnot do any correction.  A new parameter file is created to run this as a new set of measurement. The parameter file is stored at the following location:

ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/O1/H1/Scripts/DARMOLGTFs/H1DARMparams_20151028E.m 

A script used make the plot attached above and save the output as a mat file is located here:

ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/O1/H1/Scripts/DARMOLGTFs/make_sensing_HF.m 

The result of the the above script is saved at the following location and is also attached to this alog.

ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/O1/H1/Resulta/DARMOLGTFs/2015-10-28E_H1DARM_HF_sensing.mat

Executive summary: 

In regard to narrow lines, the (nearly) full O1 H1 data set is little changed from what was reported for the first week's data: a pervasive 16-Hz comb persists throughout the CW search band (below 2000 Hz), accompanied by a much weaker and more sporadic 8-Hz comb; there remain several distinct 1-Hz and nearly-1-Hz combs below 140 Hz, along with other sporadic combs. The 1459.5 hours of 30-minute FScan SFTs used here span from September 18 to the morning of January 3. The improved statistics make weaker and finer structures more visible than in the 1st week's data. As a result, many new singlet lines have been tagged, and it has become apparent that some previously marked singlets actually belong to newly spotted comb structures. The improved statistics also make it more apparent that the originally spotted combs span a broader bandwidth than marked before 

Details: 

Using 1459.5 hours of FScan-generated, Hann-windowed, 30-minute SFTs, I have gone through the first 2000 Hz of the DARM displacement spectrum (CW search band) to identify lines that could contaminate CW searches. This study is very similar to prior studies of ER7 data, ER8 data and the first week of O1 data, but for completeness, I will repeat below some earlier findings.

Some sample displacement amplitude spectra are attached directly below, but more extensive sets of spectra are attached in a zipped file. As usual, the spectra look worse than they really are because single-bin lines (0.5 mHz wide) appear disproportionately wide in the graphics

A flat-file line list is attached with the same alphabetic coding as in the figures.

Findings:

 A 16-Hz comb pervades the entire 0-2000 Hz band (and well beyond, based on daily FScans)
 A typically much weaker and sporadic 8-Hz comb (odd harmonics) is also pervasive (all harmonics are labeled in figures, even when not visible)
 A 1-Hz comb with a 0.5-Hz offset is visible from 10.5 Hz to 133.5 Hz (previously was visible from 15.5 to 78.5 Hz)
 A 1-Hz comb with zero offset is visible from 16.0 Hz to 102.0 Hz (previously was visible from 20.0 to 68.0 Hz)
 A 99.9989-Hz comb is visible to its 11th harmonic (was previously visible to its 8th harmonic)
 The 60-Hz power mains comb is visible to its 9th harmonic (was previously visible to its 6th harmonic)
 There is a sporadic comb-on-comb with 0.088425-Hz fine spacing that appears with limited spans in three places near harmonics of 77, 154 and 231 Hz (ambiguity in precise fundamental frequency)
 There is a doublet 31.4127 and 31.4149 Hz comb visible to their 2nd harmonics (previously marked as only a 31.4149-Hz comb)
 There are three near-1-Hz combs not previous appreciated:

 0.99999-Hz comb from 19.2500 to 50.2497 Hz
 0.99816-Hz comb from 30.9430 to 60.8878 Hz
 0.9992-Hz comb from 30.9738 to 48.9594 Hz

 There is a doublet comb with spacings of 2.07412 and 2.07423 Hz, visible from their 9th to 32th harmonics (18.7-66.4 Hz) 
 There is a hint of another doublet comb with spacings of 99.9735 and 99.9784 Hz, but they are marked as singlets for now


Line label codes in figures:

b - Bounce mode (quad suspension)
r - Roll mode (quad suspension)
Q - Quad violin mode and harmonics
B - Beam splitter violin mode and harmonics
C - Calibration lines
M - Power mains (60 HZ)
s - 16-Hz comb
e - 8-Hz comb (odd harmonics)
O - 1-Hz comb (0.5-Hz offset)
o - weaker 1-Hz and near-1-Hz combs (various offsets, including zero)
H - 99.9989-Hz comb
J - 31.4127 and 31.4149-Hz combs
K - 0.088425-Hz comb
t - 2.07412 and 2.07423 combs
x - single line (not all singlets in the vicinity of quad violin modes are marked, given the upconversion)

Figure 1 - 0-2000 Hz 
Figure 2 - 20-50 Hz sub-band (shows complexity of combs below ~70 Hz)
Figure 3 - 50-100 Hz sub-band (shows continuation of strongest 1-Hz comb with offset of 0.5 Hz)
Figure 4 - 1300-1400 Hz sub-band (shows how clean the noise floor is away from 8-Hz, 16-Hz lines at high frequencies

Attachments:
* Zip file with miscellaneous sub-band spectra (with line labels)
* Flat-file list of lines marked on figures