Two unrelated problems with the DAQ ongoing:

1. disk9 of the DCS raid system for h1fw0 failed at 10pm Friday night. h1fw0 lost its file system at 1:50am this morning and has not been running since then.

2. h1susim front end has failed and has caused a DAQ error for the following frontends: h1susb123, h1sush2a, h1sush34, h1sush56, h1susauxh2, h1susauxh34, h1susauxh56, h1sieb1, h1sieb2, h1seib3, h1seih16, h1seih23, h1seih45, h1psl.

both end stations have good DAQ data.

I've emailed LDAS regarding the disk failure in the LDAS server room.

For problem 2, I'm going to try restarting the DAQ data stream from those frontends.

model restarts logged for Fri 08/Aug/2014
2014_08_08 00:32 h1fw1
2014_08_08 04:32 h1fw1

unexpected restarts of h1fw1

(Stefan, Kiwamu, Koji, Alexa)

We repeated the ringdown measurement with the low gain setting (0dB compared to the nominal 30dB) and the ND0.6 filter removed (we still need to eventually revert to the nominal configuration). This time we found that the ringdown time was approximately 25µs, which is still larger than what we expected. We want to repeat this measurement with REFL from ISCT1, however, we could not find the beam for a while and then got distracted with other things...This is still to be done.

We adjusted the gains, phase rotation, I-Matrix and IMC WFS matrix. We can now engage the WFS; this increased the trans PD to ~1200 and was stable. I have attached a screenshot of the current configuration.

We increased the PSL power to 1.9W.

The beam is too high on MC3 by 1.5mm and horizotanlly off by 2.138mm in the direction away from IOT2L. This result is almost the same as the previous measurement in alog 8943, so we are fine with this off-centering.

(Richard, Cyrus, Alexa. Kiwamu)

GigE camera 08 of PR2 was first rebooted and then had to be adjusted because the image was clipped. 

Keita, Stefan

In the hope to go back to a previously established alignment we tried to restore IM1, IM2, IM3 and IM3 to two previous sets of values:
- one of the last in-vacuum days back in may (we picked May 25)
- The time of a good in-air alignment (7/17/2014 22:00 UTC)
- Interestingly, for both setting we didn't get IM4 trans out of HAM2, even after the IMC was aligned well. Thus we decided to go back to the settings we had in the morning. Here we get IM4 trans out, and can center it with IM3.

- We then decided to ignore the PRM for now, and start pointing down the PRC.

(Borja and Rai)

We followed the procedure of switching on the turbo-pump safely at the ETMY. The turbo-pump was switched on more or less about 7pm and the pressure very quickly went down to 10^-5 torr at which point we turned on the discharge gauge (about 7:40pm). We did wait until the presure was below 10^-6 torr before we powered up the power supply to the ESD HV amplifier (at about 8:30 pm). I verified, looking at the analogue readouts of the ESD HV outputs, that they were not railing as reported being a known issue in the past. This will allow me to take new charging measurements tomorrow when the ETMY pressure is safe at or below 10^-7 torr (more about this in another entry).

J. Kissel, J. Warner, G. Grabeel

Given that there is no obvious cause for the locking mechanism failure on the recently rescued GS13 s/n 574, I've elected to replace the stock delta rods (some of which had already buckled) with the much-more-robust aLIGO flexures (D0901318 and D0901319). The fragile delta rods are the primary reason the instrument needs a locking mechanism, so with the next flexures and the already-present, high-resistance pre-amp (D050358, s/n "Larry") the instrument should now be portable again with much less fear of irreparable damage. Thanks to Jim for grabbing me flexures, and thanks to Greg (already an expert in the modification procedure) for actually performing the replacement. Pictures attached.

For now, the instrument remains in my office.

New tally:
S/N     Config      Current Location
568        V        EX, in change-room, by bench
574        V        CS, In my office
578        ??       EY, on change-room racks
584        ??       EY, on change-room racks

J. Kissel, K. Venkateswara, E. Shaw

We've processed the 1 [mHz] excitation data taken over night, and it confirms our preliminary results from yesterday that the center of mass of the beam is d = 20 [um] above the suspension point. Indeed, because we shielded most of the open end of the thermal box with Ameri-stat (as shown in yesterday's pictures), the insturment's noise floor was much better. 

Note, we've also switched from Krishna's sine-wave fitting code to just grabbing the excitation amplitude from the ASD, and obtaining a transfer function value from there,
peak amplitude [rad_{pk}] = ASD [rad_{rms}/rtHz] * sqrt(binWidth) [rtHz] * sqrt(2) [pk / rms].
Since we know the response to ground tilt should tend to unity at high frequency, as any inertial sensor, and we've not changed the excitation amplitude, the collection of peak amplitudes are normalized by the highest-frequency amplitude to obtain the (beam / ground) [rad/rad] tilt transfer function. We lose a quantitative estimate of the uncertainty with this method, but we gain simplicity/clarity and it's reasonable to say from the SNR that the estimates are good to at least 20%, if not better. See attachment. 

The adjustment masses are a distance D = ~3 [in] above the C.o.M., so the change in (d = C.o.M. w.r.t the Susp. Point) per gram of adjustment weight, dm, is

dC.o.M.    D     3.0 [in]   76.2e-3 [m]
------  = --- =  -------- = ----------- = 18.1 [um/g]
  dm       M     4.2 [kg]     4.2  [kg]

As such to achieve a minimal separation, Krishna and Eric spent the rest of the morning/early afternoon removing 1.1+/- 0.05 [g]  of mass (equal to a 19.91 [um] shift in C.o.M. down toward the Susp. Point). A separation of ~1 [um] means the rejection of horizontal acceleration is

d * M_{bar}    1e-6 [m] * 4.2 [kg]        
----------  =  -------------------- = 7e-6 [rad/m]
  I_{bar}          0.59 kg.m^2

... pretty awesome! After rebalancing, they sealed the vacuum chamber (tool tight), confirmed that the new resonant frequency is 8.8 [mHz] as expected, and headed home for Seattle. 

When Krishna returns on Monday, we'll start pulling vacuum on the tank which should take about a day. From there we tweak the balance of the beam to remain within range of the autocollimator, re-measure the C.o.M.-Sus.Point separation to confirm the awesome acceleration rejection, and begin the process of connecting the system to the aLIGO DAQ.

I checked the difference in position of the Imx mirrors before and after the chamber was pumped.

I used the vacuum pressure sensor channel (HVE-LY:Y1_120BTORR) to find the times were the pumped was performed.
Then, to check the difference in position I used the times:
Before: 	2014/08/05 09:00:00 UTC
After: 	2014/08/07 10:00:00 UTC

The table shows the count difference (before and after the pump):

Difference			
        L (counts)	P (counts)	Y (counts)
IM1	10	                7.42	         -7.76
IM2	-5	               -10.6	           38.8
IM3	-27	              -21.2	           9.7
IM4	4	                31.8	           38.8

The DAC is 18 bit , which gives us a maximum of +- 131072 counts (2^18 /2 = 262144/2) in OSEMS basis (UL, LL, UR, LR).
Right now, the maximum number of used counts is 116600 (H1:FEC-104_DAC_OUTPUT_0_5), which give us a free range of 14472 more.

	UL	        LL	         UR	        LR
IM1	133.0	5.4	         -0.4	        -128.0
IM2	-425.8	-243.6	241.1	423.3
IM3	-272.3	92.1	        -105.6	258.8
IM4	-59.2	-605.7	607.7	61.2

To recover the position had it before the pump, we need a maximum of 425.8 counts.
The next table shows, in counts, how much is needed to recover the original position.
 
I am attaching the spreadsheet used for the calculations and the times series plots.

[Alexa, Kiwamu, Koji]

We found that IMC WFS B had quite small error signals. We tracked down this to be too small LO.
What we found was the LO cable had bad connection at the SMA connector. This is the same problem as Kiwamu reported before.

After recrimping the IMC WFS B cable, the all of the cables on ISC-R2 rack was reviewed.
All of the cables had the same crimping issue. Also, most of the SMA were not secured.

All of the SMA cables were recrimped and 4~5 SMAs have been replaced.

Here is the list of the LO powers in the monitor. WFS REFL45 has CH1 and CH2 with +13dBm LO power
while CH3/4 indicates very low numbers. In fact these nubers (and the corresponding RF power mons)
are not changing at all. So this could be a DAQ related problem.

=== Rack ISC-R1 U07 ===
H1:IMC-WFS_A_DEMOD_LOMONCHANNEL_1 = 16.0804
H1:IMC-WFS_A_DEMOD_LOMONCHANNEL_2 = 15.9532
H1:IMC-WFS_A_DEMOD_LOMONCHANNEL_3 = 15.999
H1:IMC-WFS_A_DEMOD_LOMONCHANNEL_4 = 16.5534
=== Rack ISC-R1 U05 ===
H1:IMC-WFS_B_DEMOD_LOMONCHANNEL_1 = 16.1007
H1:IMC-WFS_B_DEMOD_LOMONCHANNEL_2 = 16.1821
H1:IMC-WFS_B_DEMOD_LOMONCHANNEL_3 = 16.1618
H1:IMC-WFS_B_DEMOD_LOMONCHANNEL_4 = 16.3296
=== Rack ISC-R2 U38 ===
H1:ISC-RF_C_REFLAMP45M_OUTPUTMON = 17.5009
=== Rack ISC-R2 U37 ===
H1:ISC-RF_C_REFLAMP9M1_OUTPUTMON = 20.2811
=== Rack ISC-R2 U34 ===
H1:LSC-REFLAIR_A_RF9_DEMOD_LOMON = 20.6277
H1:LSC-REFL_A_RF9_DEMOD_LOMON = 20.9278
=== Rack ISC-R2 U30 ===
H1:LSC-POPAIR_A_RF9_DEMOD_LOMON = 23.059
H1:LSC-POPAIR_A_RF45_DEMOD_LOMON = 19.8342
H1:LSC-REFLAIR_A_RF9_DEMOD_LOMON = 20.6073
H1:LSC-REFLAIR_A_RF45_DEMOD_LOMON = 19.8494
=== Rack ISC-R2 U28 ===
H1:LSC-POPAIR_B_RF18_DEMOD_LOMON = 22.5656
H1:LSC-POPAIR_B_RF90_DEMOD_LOMON = 20.1851
H1:LSC-REFLAIR_B_RF27_DEMOD_LOMON = 23.0234
H1:LSC-REFLAIR_B_RF135_DEMOD_LOMON = 18.0488
=== Rack ISC-R2 U24 ===
H1:LSC-POP_A_RF9_DEMOD_LOMON = 23.3642
H1:LSC-POP_A_RF45_DEMOD_LOMON = 19.8494
H1:LSC-REFL_A_RF9_DEMOD_LOMON = 20.9328
H1:LSC-REFL_A_RF45_DEMOD_LOMON = 20.119
=== Rack ISC-R2 U18 ===
H1:ASC-REFL_A_RF9_DEMOD_LOMONCHANNEL_1 = 17.174
H1:ASC-REFL_A_RF9_DEMOD_LOMONCHANNEL_2 = 17.0824
H1:ASC-REFL_A_RF9_DEMOD_LOMONCHANNEL_3 = 16.94
H1:ASC-REFL_A_RF9_DEMOD_LOMONCHANNEL_4 = 17.3011
=== Rack ISC-R2 U16 ===
H1:ASC-REFL_A_RF45_DEMOD_LOMONCHANNEL_1 = 13.3693
H1:ASC-REFL_A_RF45_DEMOD_LOMONCHANNEL_2 = 13.471
H1:ASC-REFL_A_RF45_DEMOD_LOMONCHANNEL_3 = -75.0432
H1:ASC-REFL_A_RF45_DEMOD_LOMONCHANNEL_4 = -74.9568
=== Rack ISC-R2 U10 ===
H1:ASC-REFL_B_RF9_DEMOD_LOMONCHANNEL_1 = 17.3215
H1:ASC-REFL_B_RF9_DEMOD_LOMONCHANNEL_2 = 17.2604
H1:ASC-REFL_B_RF9_DEMOD_LOMONCHANNEL_3 = 17.2096
H1:ASC-REFL_B_RF9_DEMOD_LOMONCHANNEL_4 = 17.3011
=== Rack ISC-R2 U08 ===
H1:ASC-REFL_B_RF45_DEMOD_LOMONCHANNEL_1 = 13.5117
H1:ASC-REFL_B_RF45_DEMOD_LOMONCHANNEL_2 = 13.1913
H1:ASC-REFL_B_RF45_DEMOD_LOMONCHANNEL_3 = 13.3642
H1:ASC-REFL_B_RF45_DEMOD_LOMONCHANNEL_4 = 13.4558
 

BSC9 annulus not pumping yet -> Problem with aux. pump cart

Gerardo already pumping BSC1 and HAM3 -> will continues leak hunting on Monday

There seems to be some slow oscillating taking the outputs to higher values (1000+.) unlike the ITMX, it doesn't seem to go out of control bt the larger values are still worrysome to me.

I'll move it to isolated damped for the weekend.

Took a couple of photos of ETMY after Rai's discharging work was completed.  As with yesterday's pictures, it's tough to tell if there's any dust on the surfaces or not.

Tried focus stacking for image ETMY2.jpg in order to improve the depth of field.  Didn't seem any better than simply shooting with a smaller aperture.

All images are quite large, so there's no preview available.

RichardM, PeterK

I may not get to fixing this tonight so I at least wanted to report it.

I think Stage1 Isolation is ok but when Stage2 is Isolated, it looks like it rings up exciting stage1 and both tripping on Actuators.  HEPI is not tripping.

Currently, ITMX is under managed guardian at Isolated_Damped.

12:15 Fred et al out of LVEA
13:00 Doug, Jason done at ITMY
13:15 Gerardo to LVEA looking for pump cart, pump HAM4 annulus
13:30 Karen to EY
13:30 RichardM to EY to verify an interlock is working, back to 14:30
14:00 GregG turning on CO2 laser in squeezer bay
14:15 Fil, Manny to EX for ISC WFS cabling
15:00 Jason to BS oplev, done 15:15
16:00 Pablo to EX to work on VCO characterization

(Borja)

Several issues has not allowed me to drive the ETMY ESD until late afternoon today. At this point I was able for the first time to test, with real data, the automation code for the ESD charge measurements develped at Livingston. I did have previously adapted it for Hanford's slightly different configuration but this was the first time I was able to test its results. Unfortunately the automation on the injection, data request and analysis is not robust, not allowing for the whole process to finish several times. Also the code does not take into consideration conversion factors on the V BIAS from Voltage to counts and viceversa. I assume this is taken care in Livingston outside of the code but certainly that solution does not make it universal.

Looking at the procedure with Rai I realized that we have to be careful on the level of the driving signal amplitude to be below the minimum V BIAS used in the analysis otherwise linear approximation assumptions in the methodology are no longer valid.

Rai is leaving on Saturday and we need to apply his discharging technique before then (optimally tomorrow). Before this takes place we need to have some ESD charge measurement data so that we can compare with data taken after the discharge and see the effects observed. This time constrains has made me decide to do the measurements manually tonight. I may be able to run the automation code afterwards and compare it tomorrow with the manual measurements but this may not be possible. See manual measurements in the attached document.