The peak at 78 Hz seems to have come from a different noise coupling than the bilinear coupling of ISI motion. Yesterday we noticed that the beam diverter at EX has been open since June.  When we closed this the excess noise in the TMS QPDs disappeared, as well as the 78 Hz peak in DARM.  alog 22286

In the course of investigating the 78 Hz peak, we saw a bilinear coupling from ETMX ISI to DARM (where there is only a linear coupling from ETMY), which we had thought could be related to the niose in DARM although we could see immediately that the motion seen by the GS13s was not enough to explain any noise in DARM.  alogs 22107 and 22159 21767  

In the course of investigating this we learned a few things:

• We checked that motion of the ITMX ISI does not induce this kind of bilinear coupling.
• The noise introduced by driving depends on ISI motion not TMS motion (driving TMS produces a peak, but also moves the ISI.  Driving the ISI to create the same amount of ISI motion but orders of magnitude less TMS motion creates a similarly sized peak in DARM.)  
• Exciting the ISI in all DOFs by 1-2 orders of magnitude above the ambient motion does not produce any noise in DARM.  

Here I've attached a few plots from my last two measurements, which I made just before noticing the beam diverter was open and then repeated last night with the beam diverter closed for completeness.  The results are the same with the beam diverter open and closed, which makes sense since we now that TMS motion is not involved in this noise coupling. 

The first plot is a ratio of DARM noise to GS13 motion in nm.  You can compare this to the B&K measurements that Betsy compiled alog 22169.  It seems that the shape of this coupling is very similar to the quad cage resonances, so scattered light off of some part of the cage seems like a plausible mechanism.  

The second plot shows a projection of this noise into DARM, which is a factor 20 below DARM around 70 Hz.  

Today we replaced the roof camera with a new network camera.   It is best viewed from the monitor where the Access system is.  This monitor now has two computers connected to it.  One the access computer and the other the Roof camera computer.  you can easily switch between the two with the buttons on the monitor.  

The camera is accessed view a web browser.  Designed for Windows explorer but we have Mozilla working on this machine.   I will post the IP address on the monitor.  Standard controls password accesses the camera and you control pan/tilt and zoom with the mouse and the controls on the left side of the screen.  I will be adding go to points like a view of the gate that with a simple click the camera will adjust to.  This is proving somewhat difficult as we do not have all of the plugins installed.

If you have to re-open the screen accept the certificate and continue.  If the video seems quite small on the left side select a different video stream then return to 1 and the screen will resized.  
This is a new camera so try it out and we can make some changes and possibly get a joy stick if people want.

Commissioners asked me to add the Beckhoff controlled Servo Board outputs (FASTEXCEN & COMEXCEN) to DIAG_MAIN until the SDF Beckhoff is up. Code and example notification attached.

• This DQ shift was fairly uneventful. The duty cycle was 80% (with the maintenance period included) while the range was mainly 75 - 79 Mpc with nearly continual variation in this range.

• The most apparent problematic feature was the range drops due to ETMY saturation. While the number appeared to decrease on 6 Oct, it increased again on 7 Oct. The overall glitch rate was primarily the typical low state with lines and line-like features repeating those seen previously.

• A major event was the discovery that the EX beam diverter had been open since June when it should have been closed (See this alog and related comments.). As discussed in the alog, several persistent lines in the spectrum disappeared and a number of X and Y arm signals became comparable when this was fixed before the lock on 7 Oct.

• It was noted in the alog that a feature at approximately 0.6 Hz in the Ham3 ISI spectrum disappeared on 7 Oct (alog). This feature has been present at least since 1 July but changed character on 7 Aug and nearly disappeared on 21 Aug.

• Hveto winning channels were H1:SUS-ETMY_L2_WIT_Y_DQ for the long known 60 Hz glitches and ASC-AS_A_RF45_Q_YAW_OUT_DQ which seems to veto the ETMY saturations.

• CBC analyses yielded as the loudest triggers hardware injections and background with new SNR < 8.

More information about this DQ shift may be found here.

[Sheila, Jenne]

This morning, we discovered that the new a2l script from LLO wasn't working, because we didn't have DARM_CTRL piped over to the ASC model. 

The OMC model already had a sender part, so we only needed to add the receiver [WP 5549].  The screenshots below show the "before" and "after" of the change. 

We compiled the model, and Dave restarted it and the DAQ for us a few minutes ago. 

I ran a BruCo scan for LHO. The full report is available here:

https://ldas-jobs.ligo.caltech.edu/~gabriele.vajente/bruco_lho_1128339017/

Here is my excerpt:

• In the 10-20 Hz region the largest coherence is with DHARD_P (fig 1)
• MICH/SRCL coherence is 4-10 times below the sensitivity at low frequency, so no worrysome yet (unless the coupling is non stationary, to be investigated). Fig. 2 and 3
• PRCL is lower than the other LSC loops (fig. 4)
• The PSL periscope is a win as usual. The largest coherence is in the region 304-368 Hz, but there is a bit of lower coherence in many other bands: 150-155 / 175-185  / 202 / 240-260 / 280-290 / 551-555 / 615-623 Hz (fig. 5)
• I see coherence with OMC-LSC_DITHER_OUT at few frequencies: 80 / 96 / 128 / 288 Hz, not sure what this means
• There is coherence with PEM-EY_MAG_EBAY_SEIRACK at 281.5 Hz and 283.5 Hz.
• Above 500 Hz I can see low coherence with PEM-EY_MAG_EBAY_SUSRACK (fig. 6). This is rather small, but being an environmental channel it might be important to investigate it further.

Beside these, there are few more puzzling coherences at higher frequencies:

• 453 Hz ASC-REFL_A_RF9_I_YAW and RF45

• 485 Hz ASC-REFL_A_RF9_I_PIT and RF45 / ISI-HAM2_BLND_GS13RY_IN1_DQ

• 991.5 - 996 Hz / 1004.5 Hz ASC-OMC_A/B_SUM_OUT

• 1954.5 Hz OMC-LSC_I_OUT

• 2449.0 Hz / 2458.5 Hz LSC-PRCL_OUT

• In the region between 3300 Hz and 3400 Hz SRCL gets to quite high coherence

• 3619 Hz PRCL / SRCL / LSC-REFL_SERVO_CTRL_OUT / LSC-MCL_IN1/OUT

The attached plot shows the elapsed time of the 3 EtherCAT systems over the past 65 days. The start time is indicated about 64 days ago and no software change has been applied since then. We can see that both the corner and EX were up the entire time, wheres EY had a single downtime, when a hardware failure prompted the repalcement of a terminal. The computers and software caused no downtime.

16:30UTC

I did a short test of connecting to a large number of channels with the test conlog server (conlog-test-master):

15:08 UTC started connecting to 95462 channels
15:12 UTC added connections to 2 more channels
15:27:06 UTC stopped server

The attached plot shows the history of the controls signal over the past 24 hours. There was a step down about 12h ago in the control signals followed by a return to the old value about 6h ago.Some of the glitches were also seen in the 45MHz unit set up in the CER (shown in the 9MHz channel).

15:00UTC

TITLE: Oct 8 DAY Shift 15:00-23:00UTC (08:00-04:00 PDT), all times posted in UTC

STATE Of H1: Observing

OUTGOING OPERATOR: Patrick

QUICK SUMMARY:IFO in Observation mode ~78 Mpc. All lights in LVEA, PSL and M/E stations are off. Wind is ≤10mph. EQ sie plot is nominal. Microseism plot is steady at around .25microns/s. Patrick reported RF45 acted up a bit during his shift. IFO taken to commissioning for today’s activities

TITLE: 10/08 [OWL Shift]: 07:00-15:00 UTC (00:00-08:00 PDT), all times posted in UTC
STATE Of H1: Locked. Observing @ ~75 MPc.
SHIFT SUMMARY: Locked and observing entire shift. RF45 noise appeared to come back and subside again around 09:30 UTC. Multiple SUS ETMY saturations.
INCOMING OPERATOR: Ed
ACTIVITY LOG:

12:24 - 12:31 UTC Stepped out of control room

SUS E_T_M_Y saturating (Oct 8 07:01:29 UTC)
SUS E_T_M_Y saturating (Oct 8 07:29:17 UTC)
SUS E_T_M_Y saturating (Oct 8 07:49:59 UTC)
SUS E_T_M_Y saturating (Oct 8 08:06:32 UTC)
SUS E_T_M_Y saturating (Oct 8 09:20:57 UTC)
SUS E_T_M_Y saturating (Oct 8 09:48:58 UTC)
SUS E_T_M_Y saturating (Oct 8 10:26:45 UTC)
SUS E_T_M_Y saturating (Oct 8 10:37:34 UTC)
SUS E_T_M_Y saturating (Oct 8 10:37:37 UTC)
SUS E_T_M_Y saturating (Oct 8 10:37:39 UTC)
SUS E_T_M_Y saturating (Oct 8 11:50:20 UTC)
SUS E_T_M_Y saturating (Oct 8 12:28:17 UTC)
SUS E_T_M_Y saturating (Oct 8 13:06:51 UTC)
SUS E_T_M_Y saturating (Oct 8 14:28:34 UTC)

Have remained locked and observing @ ~78 MPc. RF45 noise appeared to come back and subside again around 09:30 UTC. Multiple SUS ETMY saturations.

07:58 - 08:04 UTC Stepped out of control room

SUS E_T_M_Y saturating (Oct 8 07:01:29 UTC)
SUS E_T_M_Y saturating (Oct 8 07:29:17 UTC)
SUS E_T_M_Y saturating (Oct 8 07:49:59 UTC)
SUS E_T_M_Y saturating (Oct 8 08:06:32 UTC)
SUS E_T_M_Y saturating (Oct 8 09:20:57 UTC)
SUS E_T_M_Y saturating (Oct 8 09:48:58 UTC)
SUS E_T_M_Y saturating (Oct 8 10:26:45 UTC)
SUS E_T_M_Y saturating (Oct 8 10:37:34 UTC)
SUS E_T_M_Y saturating (Oct 8 10:37:37 UTC)
SUS E_T_M_Y saturating (Oct 8 10:37:39 UTC)

Summary:

We had single-IFO time so I tested the new inverse actuation filter for PCALX. WP5530

Sudarshan and I believe we tracked down the factor of 2 and sign error from the initial PCALX test, see aLog 22160. We wanted to do this test to confirm that.

CBC injections:

The waveform file is: https://daqsvn.ligo-la.caltech.edu/svn/injection/hwinj/Details/Inspiral/H1/coherenttest1from15hz_1126257408.out

The XML parameter file is: https://daqsvn.ligo-la.caltech.edu/svn/injection/hwinj/Details/Inspiral/h1l1coherenttest1from15hz_1126257408.xml.gz

I did three CBC injections. The start times of the injections were: 1128303091.000000000, 1128303224.000000000, and 1128303391.000000000.

The command line to do the injections is:
ezcawrite H1:CAL-INJ_TINJ_TYPE 1
awgstream H1:CAL-PCALX_SWEPT_SINE_EXC 16384 coherenttest1from15hz_1126257408.out 1.0 -d -d >> 20151006_log_pcal.out
awgstream H1:CAL-PCALX_SWEPT_SINE_EXC 16384 coherenttest1from15hz_1126257408.out 1.0 -d -d >> 20151006_log_pcal.out
awgstream H1:CAL-PCALX_SWEPT_SINE_EXC 16384 coherenttest1from15hz_1126257408.out 1.0 -d -d >> 20151006_log_pcal.out

I have attached the log. I had to change the file extension to be posted to the aLog.

DetChar injection:

I injected Jordan's waveform file: https://daqsvn.ligo-la.caltech.edu/svn/injection/hwinj/Details/detchar/detchar_03Oct2015_PCAL.txt

The start time of the injection is: 1128303531.000000000

The command line to do the injections is:
awgstream H1:CAL-PCALX_SWEPT_SINE_EXC 16384 detchar_03Oct2015_PCAL.txt 1.0 -d -d >> 20151006_log_pcal_detchar.out

I have attached the log. I had to change the file extension to be posted to the aLog.

Today we noticed that the EX beam diverter has been open since June 18th.  We don't normally switch this so it is not guardian controlled but we "usually" leave it closed.  It is beckhoff controlled so it is not monitored in SDF.  Today TJ added all the beam diverters we don't normally change in guardian to SYS_DIAG to prevent this from happening again (it was already checking the others).

We have now locked with the beam diverter closed, and see that the QPD spectra look the same between EX and EY.   (20418 and 21767 have some history.)  The peak in DARM at 78 Hz is also not here.  We will see if it stays gone, and check soon to see if the blinear coupling of ETMX ISI motion to DARM is gone with the beam diverter closed.  

Used double coincident lockloss time this morning to installl new Pcal inverse actuation filter at X-end. I took a transfer function between RxPD and EXC with Inverse actuation filter engaged. The result is attached below. The plot shows a good agreement at lower frequencies (upto few hundred Hz) and is about 2 percent off in magnitude and  7 degress off in phase at a KHz. This is expected because the foton implemetation of filter is little diffrent from its intended response.

We will test it with CBC waveform and detchar safety injection at the next opportunity.

The script used to make this plot is committed to SVN:

/ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/O1/H1/Scripts/INVACT_PCAL/analyze_invactpcal.m