A 6.0mag EQ occurring in Tonga, 8700km distance is a better candidate than the 5.7 EQ in Miyako Japan (7400km) alog 19074, I looked at yesterday for evaluating Terramon.  Slightly further away but enough larger and it makes all the difference.  With the 5.7 EQ, I couldn't be sure there was anything on the seismos, the predictor estimated a velocity of 1.9um/sec for the R-wave.  For the 6.0 EQ, the estimate is 5.

The arrival at the site is clear on the ground STS2--see attached.  I've marked the 3 times from the predictor with thin lines and we clearly see the arrivals.  The P-wave arrival estimate is very good; the plot is 40 minutes long.  The S-wave arrival is 'late' tens of seconds and the surface wave arrives more than 5 minutes sooner than predicted.  These channels should all be calibrated in nm/sec

The second plot shows some GS-13 channels on the BS ISI stage2 and an IFO red power showing if the IFO is fully locked.  The Surface (R-phase) arrival (last arrival) does clearly change the motion on the GS13s--I've marked the apparent arrival of the Surface wave on the plots--the thicker line.  The two fat portions of the GS-13 signal correspond to locked DRMI periods, beginning and middle of plot.  So what can I say...

1) The arrival of this P-wave may have brocken the DRMI although it broke ~20+ seconds after arrival prediction.

2) Clearly, the DRMI can hold lock during the arrival of the S-phase: it arrived some 50 seconds after the middle DRMI lock section began.

3) This IFO lock break was not caused by the surface wave arrival: it broke ~6 minutes before the obvious surface waves hit-marked at thick line.

4) The DRMI did not lock while the Surface Waves had the BS GS13s rung up although later looks show the DRMI may not be soley resposible for the GS13 ring up.  Still need to understand better what the IFO state does to the ISI.  I've chosen BS GS13s as they are not in loop so maybe the most vulnerable.

5) The arrival velocity prediction is within a factor of 2 of that observed.

Observation Bit: Commissioning 

08:00 – Take over from TJ – IFO not locked 
08:07 Christina & Karen – First cleaning at End-Y 
08:10 Betsy – Running ETM charging measurements at End-X
08:31 – Beam tube cleaning crew start work on X-Arm
08:50 Christina & Karen – First cleaning at End-Y
08:55 Richard – Cabling work at End-X for ETM charging measurement
09:06 Filiberto – Going to Mid-Y to get cables
09:15 Peter – Transition End-X building to Laser Safe. Lasers are on, tables & viewports secured
09:15 Betsy – Finished with ETM charging measurements
09:30 Filiberto – Back from Mid-Y
09:45 Richard – Back from End-X
09:50 Peter – Transition End-Y building to Laser Safe. Lasers are on, tables & viewports secured 
09:55 GRB Alert – IFO not Locked
09:58 Christina & Karen – Finished with first cleaning at both End Stations
10:43 Robert – Going to End-Y 
10:52 Snack Vendor on site to restock machines
11:20 Robert – Back from End-Y
11:37 Robert – Going to End-Y
11:54 Beam tube cleaning crew break for lunch
12:18 Robert – Back from End-Y
12:53 Beam tube cleaning crew working 
13:43 Beam tune cleaning crew finished 
15:34 Robert – Going beam tube enclosure near Mid-Y
15:55 Robert – Back from Mid-Y
16:05 Hand off to Travis

HAM6, Vent Master = Hugh Radkins
https://dcc.ligo.org/E1500267

APPROVED work to be done in order of importance:

Install OMC glass stray light baffle assembly (Matt, Calum, Kate, Dan)

Install in-vac accelerometers if available (Matt, Calum, Kate, Dan)

Acoustic coupling measurements (Robert, Hugh)

DCC Vent Documents referenced in this plan:

• E1201035-v17, "aLIGO Chamber Entry & Exit Procedures"  https://dcc.ligo.org/LIGO-E1201035
• M1100039, "Hanford Checklist - HAM Door Removal"  https://dcc.ligo.org/LIGO-M1100039
• M1300464-v4, "Procedure for preparing aLIGO IFO for pumpdown"  https://dcc.ligo.org/LIGO-M1300464

Additional Documentation:

• The OMC stray light baffle assembly is shown on D0900295
• The OMC stray light baffle assembly procedure is E1500214
• Acoustic coupling measurement details provided by Robert are found at the end of this doc*.
• Payload layout update for HAM6 E1100742

SCHEDULE

TUES, June 16, 2015

1)    Transition to LASER SAFE

2)    Turn cleanrooms on around HAM6

3)    Clean area, door flange, and cleanrooms

4)    Start staging of supplies and equipment

5)    Confirm dust monitor is working

6)    Lock HEPI

WED, June 17, 2015

7)    Confirm purge air is on at HAM6

8)    Vent HAM6

9)    Remove door – Review and follow M1100039 “ Hanford checklist – HAM Door Removal”

10)  Entry chamber checklist items: Pick up floor CC wafers.  Take particle counter measurements and record:

11)  Perform acoustic coupling investigations

12)  SEI Lock ISI 

THUR, JUNE 18, 2015

13)  Start payload rework of ISI in prep for rebalancing after OMC baffle installation E1100742

FRI, JUNE 19, 2015

14)  Start prep of OMC stray light black glass shroud

MON, June 22, 2015

15)  Start install of OMC stray light black glass shroud as per E1500214

16)  Take particle measurements and record:

TUE, June 23, 2015

17)  Continue install of OMC baffle 

18)Take particle count measurements and record:

WED, June 24, 2015

19)  Continue install of OMC baffle 

20)  Install in-vac accelerometers if available – location TBD

21)  Take particle count measurements and record:

THUR, June 25, 2015

22)  Transition to LASER HAZARD

23)  Check alignment of beams in and out of OMC

24)  Transition to LASER SAFE

25)  Final rebalance ISI 

26)  Take particle count measurements and record:

FRI, June 26, 2015

27)  SEI test ISI

28)  OM SUS checkouts if needed (DAN)

29)  Chamber closeout – perform applicable exit checklist tasks E1201035.

30)  Put doors on, begin pump down.

·       Acoustic coupling measurement details (description from Robert):

Robert Schofield is interested in getting some vent time in HAM6 for investigating the resonance that promotes high acoustic coupling (we are only a factor of 2 above having ambient acoustic noise cause features in DARM (https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=18504)).

The plan would be to tap particular structures and monitor the frequency on the GS13s or on a temporarily mounted Class-A compatible accelerometer that we normally use. If we find a candidate, we will damp it using a Class-A compatible temporary damping setup, and measure the damping using an externally mounted shaker. Then we would remove anything that we put in the chamber and turn the chamber over to the next project.

ETMY BSC10, Vent Master = Betsy Weaver
https://dcc.ligo.org/E1500266

APPROVED work to be done in order of importance:

Remove charge from ETMy (Travis, Danny, Gary, Betsy, Kate, Calum, tester Arnaud)

Install VE ports to enable mounting of TMDS and new pumps (Gerardo, Kyle)

Add Krytox to beam diverters on TMS, additional QPD strain relief (Corey, Keita)

DCC Vent Documents referenced in this plan:

• E1201035-v17, "aLIGO Chamber Entry & Exit Procedures"  https://dcc.ligo.org/LIGO-E1201035
• M1100039, "Hanford Checklist - HAM Door Removal"  https://dcc.ligo.org/LIGO-M1100039
• M1300464-v4, "Procedure for preparing aLIGO IFO for pumpdown"  https://dcc.ligo.org/LIGO-M1300464

Additional Documentation:

• The ECR approving the use of Krytox LVP is E1400353
• The Beam Diverter assembly is described in E1100686-v3
• The ETM/ERM Gap discharge procedure is described in T1500101

SCHEDULE

FRI-MON early morning time permitting, June 12-15, 2015

1)    Turn cleanrooms on

2)    Clean area, door flange, and cleanroom

3)    Start staging of supplies and equipment

4)    Confirm dust monitor is working

MON, June 15, 2015

5)    Transition to LASER SAFE

6)    CDS: Control systems need to be up and running through vent – confirm that normal TUES CDS maint does not interfere with controls.

7)    Confirm purge air is on

8)    Close gate valves

9)    Vent BSC10

10)  Remove door – Review and follow M1100039 “ Hanford checklist – HAM Door Removal”

11)  VE work – installation of 2 ports

TUES, June 16, 2015

12)  Entry chamber checklist items: Pick up floor CC wafers.  Take particle counter measurements and record:

13)  Inspect optic – Calum, Kate, Travis, Betsy, Danny, Gary

14)  Transition to LASER HAZARD

15)  Perform TMS work

QPD strain relief, rebalance TS and check alignment

Krytox on BD

Take particle counter measurements and record:

16)  Transition to LASER SAFE

WED, June 17^th, 2015

17)  Discharge ETMy, noting details of measurements for alog, as per procedure T1500101.  Inspect all EQ stops at TM stage for proximity.  Take particle counter measurements throughout and record:

18)  SUS ETMy TF tests.

19)Chamber closeout – note, a truncated exit chamber checklist will be executed due to risk of recontamination of charge.

20)  Put door on, start pump down.

THUR, June 18, 2015

21)  Perform ESD/OL charge measurements.

ETMX BSC9 - Vent Master = Betsy Weaver
https://dcc.ligo.org/E1500265

APPROVED work to be done in order of importance:

Remove charge from ETMx (Travis, Danny, Gary, Betsy, Kate, Calum, Tester Arnaud)

Install VE ports to enable mounting of TMDS and new pumps (Gerardo, Kyle)

Add Krytox to beam diverters on TMS, additional QPD strain relief (Corey, Keita)

Fix clipping on TMSx (Corey, Keita)

Remove most bias from ETMx (Betsy, Travis or Danny, Gary)

Swap ESD feedthru, time permitting (Richard, Betsy)

Check ETMx PUM UL coil/cable seating, attempt to fix excess noise

as per Bug 929, alog 13047 (Betsy, Travis or Danny, Gary)

DCC Vent Documents referenced in this plan:

• E1201035-v17, "aLIGO Chamber Entry & Exit Procedures"  https://dcc.ligo.org/LIGO-E1201035
• M1100039, "Hanford Checklist - HAM Door Removal"  https://dcc.ligo.org/LIGO-M1100039
• M1300464-v4, "Procedure for preparing aLIGO IFO for pumpdown"  https://dcc.ligo.org/LIGO-M1300464

Additional Documentation:

• The ECR approving the use of Krytox LVP is E1400353
• The Beam Diverter assembly is described in E1100686-v3
• The ETM/ERM Gap discharge procedure is described in T1500101

SCHEDULE

FRI-MON early morning permitting, June 12-15, 2015

1)    Turn cleanrooms on

2)    Clean area, door flange, and cleanroom

3)    Start staging of supplies and equipment

4)    Confirm dust monitor is working

MON, June 15, 2015

5)    Transition to LASER SAFE

6)    CDS: Control systems need to be up and running through vent – confirm that normal TUES CDS maint does not interfere with controls.

7)    Confirm purge air is on

8)    Close gate valves

9)    Vent BSC9

10)  Remove door – Review and follow M1100039 “ Hanford checklist – HAM Door Removal”

11)  Entry chamber checklist items: Pick up floor CC wafers.  Take particle counter measurements and record:

12)  Inspect optic – Calum, Kate, Travis, Betsy, Danny, Gary

13)  Transition to LASER HAZARD

14)  Start TMS work

QPD strain relief, rebalance TMS and check alignment

Krytox on BD

Possibly fix clipping, recheck alignment

Take particle counter measurements and record:

TUES, June 16, 2015

15)  Finish TMS work.  Take particle counter measurements:

16)  Transition to LASER SAFE

17)  VE work – installation of 2 ports

WED, June 17, 2015

18)  Debias ETMx via watching pointing on oplev, note removing ~300 counts will be good enough.  Check TFs to ensure full suspension after complete.  Take particle counter measurements:

19)  Check cabling to ETMx L2 UL AOSEM – lots of sensor noise

20)  Swap and reterminate ESD feedthru (maybe – will skip if not enough time to complete)

THUR, June 18, 2015

21)  Discharge ETMx, noting details of measurements for alog, as per procedure T1500101.  Inspect all EQ stops at TM stage for proximity.  Take particle counter measurements throughout and record:

22)  SUS ETMx TF test

23)  Chamber closeout – note, a truncated exit chamber checklist will be executed due to risk of recontamination of charge.

24)  Put door on, start pump down.

FRI, June 19, 2015

25)  Perform ESD/OL charge measurements.

DCC References

ETMX BSC9
https://dcc.ligo.org/E1500265

ETMY BSC10
https://dcc.ligo.org/E1500266

HAM6
https://dcc.ligo.org/E1500267


Plan for Contamination Control prep for the End Stations vent:

(prepared by Jeff Bartlet and Betsy Weaver)

    1). Friday morning Christina & Karen will do the first cleaning.
    2). Sunday Kyle will turn on the cleanrooms.
    3). Monday morning Jeff will take dust readings near the roof.
    4). Monday morning Christina & Karen will do the second cleaning.
    5). Jeff will monitor the dust counts during the door removals.

At Sheila request, I look into some of the long locks to see if the coupling of SRCL to DARM is stationary or not. In brief, as far as I can tell, it looks stationary.

I took 5 hours of data from 1118016016, and compute the coherence between DARM and SRCL with 0.1 Hz resolution (first plot). There is some coherence, especially in the region between 20 and 70 Hz. 

Then I computed the coherence and transfer function for short 10 seconds-long periods, with a resolution of 1 Hz. I computed the average and standard deviation of the coherence and the absolute  value of the TF. The second plot shows the coherence and the transfer function: the shaded regions correspond to the standard deviation. It seems to me that there aren't large flutuations as was the case in the past.

09:55 Received a GRB alert. Unfortunately LHO was not locked at the time. The GRB alert alarm handler worked well.    

Leonid, Betsy

Between yesterday afternoon and this morning, we obtained 4 more good ETMx charge measurements using the optical lever.  Soon to be attached are the trends of the data compared to the previous JAN and APRIL measurements.  Note, as has been stated over the last few days, the LL quadrant of the ESD does not appear healthy, and therefore is the only data point showing a lot of scatter.  This morning Richard went to End X and found that it is shorted.  We suspect it is likely shorted at the feedthru which is still the "old" style.  We plan to swp the feedthru and re-terminate the ESD in-vac cable during next weeks vent - this will bring it up-to-date with the EY ESD and both L1 ESD connections.

On Wednesday night, because we couldn't get much past DRMI due to wind, I tried changing the St1 blend on the BS ISI to match the "windy" blend used on the ITMs. This is a change that the commissioning crew and I have agreed should happen for a while, but we didn't want to disturb the IFO during data taking. Previously the BS was running the 45mhz blends in X&Y, while the ITM's were running the 90mhz blends in the beam direction. Looking at CPS spectra, this meant that the BS was moving a lot more at low frequency than the ITM's (see first attached spectra, BS is red and blue, ITM beam directions are in purple and black). Now that I've switched the BS, it is moving the same as the ITMs. Sheila suggested I look at the ASC signals during the subsequent lock (I left the blends because it was still "windy") to see if this affected the angular control of the IFO. I think at low frequency this made an improvement in MICH (second and third plots, which are ASC yaw and pitch for MICH, green is before, brown after on both). I checked the ground at both times to make sure the input motion was the same and there are differences, but not huge (last plot, green and brown are before, red and blue are after, solid is Y, dashed is X). I don't show Z but it was even more similar.

ER7 will end at 08:00 on Sunday the 14th.
 
The Vent prep work will start Sunday the 14th. 
	Betsy will be the vent coordinator for the End-X and End-Y activities 
	Hugh will be the vent coordinator for the HAM-6 activities
For the vent plan, see aLOG 19085

Beam tube cleaning continues on the X-Arm

Bubba - working on fan repairs in the Mechanical building

Kyle – Prep work for the vent. Goal is to have the doors ready to come off at 12:00 Monday the 15th

Peter – Will transition the end stations to Laser Safe by locking the laser enclosures and verifying all view ports are in place. The laser will not be shut down until Monday when the doors are ready to come off. 

Since my last post the wind is beinging to pick up again, not anything crazy but gusts above 20mph. I have gotten a few tries very close, at 607 I made it all the way to LOWNOISE_ESD_ETMY but something always seems to break it.

On my last attempt, ETMY and ITMX bounce and roll modes were badly rung up, I managed to damp them below 10^-11 and then as soon as I went to move on it broke lock.

Cleaning crew will be heading into the end stations in a few minutes.

Looks like I failed for tonight. Handing it off to Jeff here in a min.

model restarts logged for Thu 11/Jun/2015

no restarts reported

The winds died down about 2.5 hours ago but locking has still been unsuccessful. Breaks lock consistantly at REFL_TRANS. I have tried a handful of initial alignments, but with the same results.  I eventually  got past REFL_TRANS by touching PRM a little, but at DRMI_ON_POP I couldn't recover RF90 and RF18, seemed like me touching PR2 made things worse not better like it normally would.

I have a few more ideas I will try before I wake someone up for help.

Walked on to a very windy site(40+mph winds) and no locking for about 10 hours. Since then, the winds have died down a little but locking is still not happening. I can't get it past DRMI, most often it will get stuck on LOCK_DRMI_1F for a very long time.

Here's to hoping the wind will die down some more.

Andy, Jess

Since the 79.2 MHz fixed frequency source was powered off alog, we have not seen any RF beatnote/whistles in DARM at Hanford. We see them in DARM at Livingston, however, but the mechanism is much more complicated than Hanford. The mechanism is not the PSL VCO beating against a fixed frequency.

Since we still see whistles at Hanford in auxiliary channels, we thought we'd revisit them, to see if that gives us clues for L1. We looked at the lock of Jun 11 starting at 6 UTC. We see whistles in PRCL, LSC-MCL, and sometimes in SRCL. Choosing two times, we find that the whistles correspond exactly to a beatnote of the PSL VCO frequency with a fixed frequency of 78.5 MHz (or something within a few hundred Hz of that). So it's the same simple mechanism as before, just against a different frequency.

Attached are plots of two times in PRCL where we predict the exact shape of the whistle, using IMC-F as a proxy for the PSL VCO frequency. SRCL and MCL are similar. We'll go back and check other locks to see if there's any evidence for other frequencies or shifts in the frequency.

00:00 The ifo locked right before I came in. Wind speed is <20 mph. 90 mHz blend filter is used for BSC2.

           I noticed the BS oplev sum is saturated (> 80000 counts). Is this alright? It's been around this value for 10+ days.

01:55 There's a big bump at ~30 Hz that caused a big dip in the BNS range. SUS Oplev plots didn't show anything suspicious. The bump at this frequency happened through out the night, just not as big.

02:00 A 4.7 MAG earthquake in Ecuador shook PR3 a little and BNS range dropped slightly (from 61 Mpc to 60 Mpc), but that's all it did. No WD tripped. 

08:00 We've been locked for 8+ hours and still going strong at 61 Mpc! We had 5+ hours of coincidence with Livingston tonight. Handling the ifo to Jeff B.

Dan, Travis

Tonight during our long lock we measured the decay time constant of the ITMX bounce mode.  At 10:10 UTC we set the intent bit to "I solemnly swear I am up to no good" and flipped the sign on the ITMX_M0_DARM_DAMP_V filter bank and let the bounce mode ring up until it was about 3e-14 m/rt[Hz] in the DARM spectrum.  Then, we zeroed the damping gain and let the mode slowly decay over the next few hours.

We measured the mode's Q by fitting the decay curve in two different datasets.  The first dataset is the 16Hz-sampled output of Sheila's new RMS monitors; the ITMX bandpass filter is a 4th-order butterworth with corner frequencies of 9.83 and 9.87Hz (the mode frequency is 9.848Hz, +/- 0.001 Hz).  This data was lowpassed at 1Hz and fit with an exponential curve.

For the second dataset I followed Koji's demodulation recipe from the OMC 'beacon' measurement.  I collected 20 seconds of DELTAL_EXTERNAL_DQ data, every 200 seconds; bandpassed at 9 and 12Hz, demodulated at 9.484Hz, and lowpassed at 2Hz; and collected the median value of the sum of the squares of the demod products.  Some data were neglected on the edges of the 20-sec segment to avoid filter transients.  These every-200-sec datapoints were fit with an exponential curve.

Results attached; the two methods give different results for Q:

RMS channel: 594,000

Demodulated DARM_ERR: 402,000

I fiddled with the data collection parameters and filtering parameters for both fits, but the results were robust.  When varying parameters for each method the results for Q were repeatable within +/- 2,000, this gives some sense of the lower limit on uncertainty of the measurement.  (The discrepancy between the two methods gives a sense of the upper limit...)  Given a choice between the two I think I trust the RMS channel more, the demod path has more moving parts and there could be a subtlety in the filtering that I am overlooking.  The code is attached.