10-12-15 Morning Meeting Minutes

·      SEI – Running 45mHz blends are running on the BSC ISIs, may need to change them soon.

·      SUS - Needs charge measurement tomorrow.

·      ISC – Needs noise measurement of LV esd

·      Vac – Leak testing, no N2 deliveries this week.

·      Fac – Work with the water tank, starting again on the crack sealing on beam tube sealing during Observing.

·      PEM – Completed tamper inj at CS, but still needs ends. Needs about a two hours for both end stations.

·      Maintenance items:

o   ESD measurement - Keita

o   Slow controls testing DAQ – JH

o   PCal calibrations X/Y ends (Needs ETMs aligned) – Pcal team

o   Copy HW Inj Infrastructure to PCalX – Jeff K

o   Return HEPI pump pressure sensors to norm – Hugh

o   PEM inj, possible gluing to mirror in PSL – Robert

o   Finish deinstallation of old roof cam - Richard

o   PEM temp sensors on chambers – Richard

o   Fire dept. maintenance on hydrants

o   Plumbing in the LVEA – Jeff B.

o   Phone identification signs in ends/mids – Bubba

o   Jim wants to take some transfer functions on HAM BSC (probably not yet)

o   Load from MY to staging building – Jodi

o   Pulling cables from ends to 250 mark for ion pumps – CDS

o   Sataboy, storage data for DMT, work - Carlos

• Title: 10/12 DAY Shift: 15:00-23:00UTC (8:00-16:00PDT), all times posted in UTC
  

• State of H1: Observing
  

• Outgoing Operator: Cheryl
  

• Quick Summary: She seemed to have a good shift, stayed locked with calm winds and no earthquakes. Microseism picked up again 8 hours ago. Blends are still in the 45mHz for all BSC ISIs

Title:  10/12/2015, Owl Shift 07:00 – 15:00UTC (00:00 – 08:00PT)

State of H1: Locked in NOMINAL_LOW_NOISE at 76.6Mpc. 

Outgoing Operator: JeffB

Quick Summary: 

Chris Biwer doing hardware injections - ending around 8:10UTC (see his alog)

Instructions to switch ISI Blend Filters after lock loss, and try the Quiet 90 filters on BSC chambers.

Finished with hardware injection tests. More details later.

Activity Log: All Times in UTC (PT)

23:00 (16:00) Take over from TJ
02:30 (19:30) Jeff K. left the site
03:57 (20:57) Chris – Running hardware injections for the next 72 minutes. 
			Approved by Mike L., Notified LLO, Will not drop out of Observing
04:30 (21:30) GRB Alert – In one hour stand down
04:58 (21:58) ETMY saturation event during GRB stand down
05:30 (22:30) Finished one hour stand down. 
06:15 (23:15) Chris – Restarted hardware injections
07:20 (00:20) Turn over to Cheryl
	

Title: 10/11/2015, Evening Shift 23:00 – 07:00 (16:00 – 00:00) All times in UTC (PT)

Support: Jeff K, 

Incoming Operator: Cheryl

Shift Summary: 
- 03:57 – Chris running hardware injections. He has Mike’s approval and did not go out of Observing
- 04:30 Received GRB alert. Both sites in Observing mode. In stand down for 1 hour
Chris has stopped the hardware injections he was running.  Per Verbal Alarm - Last injection stopped at 04:28:17, the GRB was time stamped at 04:30:28.  
 	
Good shift. IFO locked in Observing for 14 hours. Low wind and seismic. There were several ETMY saturations. There were 3 mag 5 or greater earthquakes during the shift, but these did not noticeably affect the IFO.      

We're going to continue with the hardware injection tests again after waiting for the external trigger.

The schedule will be updated with the following lines:
1128666017 1 1.0 ringburstinj1b_1126259456_
1128666377 1 1.0 ringburstinj2b_1126259456_
1128666737 1 1.0 ringburstinj3b_1126259456_
1128667097 1 1.0 ringburstinj4b_1126259456_
1128667457 1 1.0 ringburstinj5b_1126259456_
1128667817 1 1.0 ringburstinj6a_1126259456_
1128668177 1 1.0 ringburstinj6b_1126259456_
1128668537 1 1.0 ringburstinj7b_1126259456_
1128668897 1 1.0 ringburstinj8a_1126259456_
1128669257 1 1.0 ringburstinj7a_1126259456_
1128669617 1 1.0 ringburstinj8b_1126259456_
1128669977 1 1.0 ringburstinj9a_1126259456_
1128670337 1 1.0 ringburstinj10a_1126259456_
1128670697 1 1.0 ringburstinj11a_1126259456_
1128671057 1 1.0 ringburstinj12a_1126259456_
1128671417 1 1.0 ringburstinj13a_1126259456_
1128671777 1 1.0 ringburstinj14a_1126259456_
1128672497 1 1.0 ringburstinj15a_1126259456_

Beginning hardware injection test. The schedule will be updated with:

1128657857 1 1.0 ringburstinj1a_1126259456_
1128658037 1 1.0 ringburstinj1b_1126259456_
1128658217 1 1.0 ringburstinj2a_1126259456_
1128658397 1 1.0 ringburstinj2b_1126259456_
1128658577 1 1.0 ringburstinj3a_1126259456_
1128658757 1 1.0 ringburstinj3b_1126259456_
1128658937 1 1.0 ringburstinj4a_1126259456_
1128659117 1 1.0 ringburstinj4b_1126259456_
1128659297 1 1.0 ringburstinj5a_1126259456_
1128659477 1 1.0 ringburstinj5b_1126259456_
1128659657 1 1.0 ringburstinj6a_1126259456_
1128659837 1 1.0 ringburstinj6b_1126259456_
1128660017 1 1.0 ringburstinj7a_1126259456_
1128660197 1 1.0 ringburstinj7b_1126259456_
1128660377 1 1.0 ringburstinj8a_1126259456_
1128660557 1 1.0 ringburstinj8b_1126259456_
1128660737 1 1.0 ringburstinj9a_1126259456_
1128660917 1 1.0 ringburstinj10a_1126259456_
1128661097 1 1.0 ringburstinj11a_1126259456_
1128661277 1 1.0 ringburstinj12a_1126259456_
1128661457 1 1.0 ringburstinj13a_1126259456_
1128661637 1 1.0 ringburstinj14a_1126259456_
1128661817 1 1.0 ringburstinj15a_1126259456_
1128661997 1 1.0 ringburstinj16a_1126259456_

Locked in LOW_NOISE at 22.2W, 68Mpc range. LHO has been in Observation mode for past 10 hours. LLO has also been locked with comparable range during this stretch. Wind is calm (1 to 3 Mph); Seismic activity has been quite during the shift. 

   There have been a few ETMY saturation events, but have not observed any problems with the RF45 EOM.    

Title:  10/11/2015, Evening Shift 23:00 – 07:00 (16:00 – 00:00) All times in UTC (PT)

State of H1: At 23:00 (16:00) Locked at NOMINAL_LOW_NOISE, 22.2W, 70Mpc. 

Outgoing Operator: TJ

Quick Summary: Environmental conditions are good. IFO in Observing mode. All appears to be normal.       

Title: 10/11 Day Shift 15:00-23:00 UTC (8:00-16:00 PST).  All times in UTC.

State of H1: Unlocked, high winds and high microseism

Shift Summary: Locked until 21:24, haven't been able to relock since due to environment issue.

Incoming operator: Jeff B.

Activity log:

• 16:21 Reached Nominal Low Noise, Sheila will start A2L measurements
• 17:06 Observing, accepted blend changes in SDF
• 17:29 ETMY sat
• 18:03 ETMY sat
• 18:58 Realized that I've been spelling summary as "summery" in all of my ops posts
• 19:25 Jeff K opened H1CALCS Tp 0
• 20:22 Jeff K closed H1CALCS Tp 0
• 21:40 ETMY sat (x2)
• 22:23 ETMY sat

J. Kissel, M. Oliver

Miquel and I are doing some fun Sunday afternoon investigations of the 1 [Hz] comb for the CW group (see LIGO wiki page). Since we see that the power of the comb evolves with time, we've gathered some DELTAL EXTERNAL data as a test point to compare it against the version stored in the frames. Accessing the test point via DTT opened up a test point, naturally. One would have nominally expected opening up test points on any front end to take us out of observation mode BUT CAL-DELTAL_EXTERNAL happens to be computed on the same front end as the continuous wave injections, which -- because they need to access the H1:CAL-INJ_CW_EXC test point continuously -- has been flagged as "OK to have test points activated." (Note, this is why Giles, the H1 IFO automated voice robot, announced that CW injections had started when I hit "start" on the first bit of data gather in the DTT session). Of course, this is a monitor test point, so it had zero effect on the functionality/operation of the IFO, so remaining in observation mode was totally acceptable (even though admittedly, we didn't think of it when getting started). 

The test point was activated at 19:25 UTC (12:25 PDT) to 20:22 UTC (01:22 PDT).

Stay tuned for analysis of the data.

Jeff Kissel noticed a ~300hz line in the glitch gram on the control room wall. Seems like it started with this lock but has been getting worse. Screen shots attached.

Observing at ~70Mpc.

Winds have picked up a bit, around 15-20mph, so I am not sure if this lock will hold with these blends. On the front Striptool AS90 has a fairly large oscillation.

Microseism seems to be on its way down, very slowly. We are now in a range of .3-.5 um/s.

LLO is still observing as well.

Jim W. suggestd that we try out the 45mHz blends if we can't lock due to the high microseism. Just before I came on shift, Travis and Sheila switched them over for the X and Y directions on BS, ETMY, EMTX, ITMY, and ITMX. They decided to do this because of the low winds and high microseism.  This seemed to have helped us out quite a bit. Before the change, they struggled getting to lock DRMI, with them switched it only took us a few tries before we were all the way to Nominal Low Noise.

I will be accepting these blend changes in the SDF so we can move into Observing.

Furture operators should change them back if the winds pick up (Sheila says anything above 20 might be too high for these blends), but keep in mind this may drop lock.

Josh, Andy

Yesterday's hveto page found a very constant rate of 30-40Hz glitches in DARM were vetoed by a population of 10-15Hz glitches in the End-Y QPDs (ASC-Y_TR_{A,B}_{NSUM,YAW,PIT}_OUT_DQ). Fig1 shows the time/freq of the DARM triggers and the ASC-Y triggers that vetoed them, Fig 2 shows the time/freq of all DARM triggers and the ones that got vetoed, and Fig 3 shows how the ranking statistic found all ASC-Y channels to be correlated. A .txt file with the times of vetoed DARM triggers is attached in case folks want to look at other channels around those times. 

Fig 4 shows DARM, figs 5,6 show ASC-Y channels, figs 7,8 show zoomed specgrams to see the frequency. What we see are strong scattering arches around 8 and 16 Hz in all of the End-Y QPD channels, at the same time as similarly shaped fringes in DARM around 48Hz. I think DARM (more sensitive to scatter, potentially, at higher frequencies)  is seeing the 6th overtone of the 8Hz arch (multiple reflections?). The higher overtones are sometimes visible in the QPDs too. 

So...what scatterer/optics is moving too much? We know [1] that f_fringe(t) = 􏰁􏰁􏰁􏰁􏰁abs(2 v_sc(t) / lambda)􏰁. Where v_sc(t) is the time derivative of the position of the scatterer x_sc(t). The time between peaks is about 3.5 seconds, but that is half the period because of the abs() so it's a ~7 second period or 0.14Hz motion of the scatterer. 􏰁􏰁􏰁 

Note: We checked and the beam diverter is closed (H1:SYS-MOTION_Y_BDIV_A_POSITION = 1). 

Note 2: Today's hveto page hasn't finished yet, but no reason to believe this isn't happening still.  

[1] Accadia, T., et al. "Noise from scattered light in Virgo's second science run data." Classical and Quantum Gravity 27.19 (2010): 194011.

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

Elli and Stefan showed in aLOG 20827 that the signals measured by AS 36 WFS for SRM and BS alignment appeared to be strongly dependent on the power circulating in the interferometer. This was apparently not seen to be the case in L1. As a result, I've been looking at the AS 36 sensing with a Finesse model (L1300231), to see if this variability is reproducible in simulation, and also to see what other IFO variables can affect this variability. 

In the past when looking for differences between L1 and H1 length sensing (for the SRC in particular), the mode matching of the SRC has come up as a likely candidate. This is mainly because of the relatively large uncertainties in the SR3 mirror RoC combined with the strong dependence of the SRC mode on the SR3 RoC. I thought this would therefore be a good place to start when looking at the alignment sensors at the AS port. I don't expect the SR3 RoC to be very dependent on IFO power, but having a larger SR3 RoC offset (or one in a particular direction) may increase the dependence of the AS WFS signals on the ITM thermal lenses (which are the main IFO variables we typically expect to change with IFO power). This might therefore explain why H1 sees a bigger change in the ASC signals than L1 as the IFOs heat up. 

My first step was to observe the change in AS 36 WFS signals as a function of SR3 RoC. The results for the two DOFs shown in aLOG 20827 (MICH = BS, SRC2 = SRM) are shown in the attached plots. I did not spend much time adjusting Gouy phases or demod phases at the WFS in order to match the experiment, but I did make sure that the Gouy phase difference between WFSA and WFSB was 90deg at the nominal SR3 RoC. In the attached plots we can see that the AS 36 WFS signals are definitely changing with SR3 RoC, in some cases even changing sign (e.g. SRM Yaw to ASA36I/Q and SRM Pitch to ASA36I/Q). It's difficult at this stage to compare very closely with the experimental data shown in aLOG 20827, but at least we can say that from model it's not unexpected that these ASC sensing matrix elements are changing with some IFO mode mismatches. The same plots are available for all alignment DOFs, but that's 22 in total so I'm sparing you all the ones which weren't measured during IFO warm up. 

The next step will be to look at the dependence of the same ASC matrix elements on common ITM thermal lens values, for a few different SR3 RoC offsets. This is where we might be able to see something that explains the difference between L1 and H1 in this respect. (Of course, there may be other effects which contribute here, such as differential ITM lensing, spot position offsets on the WFS, drifting of uncontrolled DOFs when the IFO heats up... but we have to start somewhere).