The piezo low-pass filter box (D1500001) S/N S1500001 was installed.

Measured voltages at the 15-pin analog interface
pin     before   after           signal
1        0.110    0.016          V-MON-X
2        0.206    0.143          V-MON-Y
3        0.109    0.160          V-MON-1
4        0.206    0.143          V-MON-2
5        0.000    0.000          V-MON-3
6        0        4.664          Servo-1 OFF/ON
7        0        4.656          Servo-2 OFF/ON
8                                GND
9        0.160    -0.476         SGS-MON-X
10       1.431    1.173          SGS-MON-Y
11       0.163    -0.472         SGS-MON-1
12       1.430    1.173          SGS-MON-2
13       -13.15   -13.12         SGS-MON-3
14       4.824    4.821          OFL1
15       4.821    4.819          OFL2

DIP switches 1 & 2 were switched from ON to OFF.

To bring the beam back, most of the adjustment was done with the control slider for pitch, which went went a
couple of hundreds on the slider to ~4000.  The yaw slider was adjusted by a few hundred.




Kiwamu, Richard, Peter

distance from the PSL table to the acoustic enclosure wall = 4' 10-11/16"
distance from acoustic enclosure wall to periscope face plate = 2' 9"

The face plate is labelled as IO ALS M5.

Sudarshan, Thomas, Darkhan, Travis, Rick

Summary

At 104.7. Hz the displacement DARM ASD was 1.26e-16 m/rtHz , the ASD according to the Pcal line was 2.07e-16 m/rtHz. The ratio is 1.64, with Pcal reporting a higher ASD.

Details:

We were running the Pcal calibration line at 104.7 Hz at LHO ENDY (25000 cts. excitation amplitude) during the lock stretch

After calibration of the power going to the test mass using the Working Standard at Yend and using the radiation pressure induced displacement equation

x= 2*P*Cos(theata)/M*c*(2*pi*f)^2

we have calculated (preliminary) the calibration value for the Transmission Monitor photodetector to be

x= 1.68e-12 (1/f^2)*(m/V)

Attached is the calibrated plot of Pcal ASD together with the DARM ASD in the region near the calibration line.

Found one of the channels for PEM AA chassis at EX (CH24) has an offset of about ~1500cts. Will pull unit on Tuesday to troubleshoot.

The attached plot shows coherence between a microphone in the electronics bay and DARM. It may be worth investigating acoustic coupling to the electronics. 

   Posted below are the OpLev 12 hour trends.

At GPS time 1107854779 [2015-02-13 09:26:03 UTC], H1 appeared to unlock but the ISC_LOCK guardian state didn't change. The attached plot shows the X-arm power and the guardian state to confirm (hopefully).

At the time of writing the guardian is still reporting 'DC_READOUT' as the current state, while there is no circulating power in the arms. The other guardian nodes (e.g. ISC_DRMI) did respond to the lockloss, however, so I presume it's just an oversight in the ISC_LOCK DC_READOUT state definition to check that the other guardians are still nominal, or that the arms are actually locked.

I'm always a step behing the on-site commissioners (good job!), but here is the list of coherence for the 2+ hours lock:

https://ldas-jobs.ligo.caltech.edu/~gabriele.vajente/bruco_1107760396/

Here are my main comments on it:

• In the low frequency range (below 20 Hz) there is coherence with some suspension signals from HAM1, HAM2, ITMY, see the first three attached plot for some examples. In particular coherence is high with HAM1/2 at 15 Hz and ITMY at 30 Hz. I'm not very familiar with those systems, so I probably didn't choose very meaningful channels, but if you look into the full table you'll see many of them.
• It's not high, but nevertheless significant: there's coherence between 10 and 100 Hz with PEM-EY_MAG_VEA_FLOOR_*
• Between 40 and 1000 Hz there is broadband, even if not large, coherence with POP_LF, probably due to intensity noise. However, this is the largest coherence in most of this band
• At 75 Hz there is coherence with the magnetometers at the Y end: I guess it's the well known ring heater line
• There is a "bump" of coherence with IMC angular signals between 287 and 300 Hz. This might be one of the beam jitter resonances. There are similar bumps at about 550 Hz and 820 Hz

All day next Tuesday will be scheduled for maintenance
Model changes planned for next Tuesday

Sheila and Richard will install a low pass filter box between the IO piezo controller and periscope
PCAL was calibrated at end X yesterday
PCAL may have a bad AOM at end X

There is a request to label the analog camera images

model restarts logged for Thu 12/Feb/2015
2015_02_12 00:56 h1fw0
2015_02_12 15:33 h1fw1
2015_02_12 17:14 h1broadcast0

two unexpected restarts (first h1fw0 unexpected restart since 11 days ago). Broadcaster reconfigure for DMT channel addition. Conlog frequently changing channels report attached.

Dan, Jeff, Sheila

Tonight we had some more fun noise hunting.  Turning the power up to 8 Watts was easy, but didn't improve the noise so much since we are mostly not shot noise limited. 

• First, when we got to DC readout we noticed that someone did a nice job damping the ETMY violin mode, reducing the peak in the asd by about a factor of 2.  This allowed Dan to turn on one stage of whitening in the OMC DCPDs, which helped improve the noise floor.  
• We further reduced the gain of the ETMX oplev damping (by a factor of 2 for a gain of -5).  This reduced coherence around 10 Hz and helped the DARM noise floor.
• We have been running all day with the ESD linearization on, this seems to be fine. 
• We had the ISS second loop on for the first long lock of the night, it has been off ever since.  

This gave us a lower noise floor, we sat here from 5:28:10 UTC Feb 13th to 5:41:29 UTC, with the intent bit undisturbed. 

We then made a single destructive attempt to reduce the ESD bias voltage, we'll have to come back to this.  :)

On the next lock we decided to try increasing the input power.  This was suprisingly easy, we have now been sitting at 8 Watts input power since 7:03:43 UTC.  We have been adjusting the BS alignment by hand every 10-15 minutes or at 10 Watts.  We have watched the AS36Q WFS signals while we do this, and can see that they are not always correct (zero does not always give us the best AS90).  BS yaw dramatically improves the intensity noise coupling.  It seems as though the IFO would stay locked like this all night if we sat here and adjusted the BS once in a while.  We are leaving it locked and undisturbed.

In the attached plot, the green trace is earlier today, The blue trace is with 1 stage of DCPD whitening on and the ISS second loop on, which is injecting noise at around 700 Hz.  The red trace is now, with 8 Watts input power, BS YAW oplev damping gain reduced, and the ISS second loop off.  You can see that we are not really shot noise limited, as increasin the power by a factor of 2.8 only gives us a small improvement at high frequencies.  Something is clearly wrong with the calibration.  

I examined the sidebands of the OMC ASC dither lines today.  The excess noise around these lines is disappointingly broad, roughly +/-2Hz.  There are sidebands around the dithers at +/-0.18, 0.45, 0.49, and 1.5Hz.

The attached figure compares the sidebands of the first dither line (middle plot) to the low-frequency DARM noise (top plot).  The bottom plot is the noise around the violin mode.

Sheila, Dan, Elli, Kiwamu, Lisa, Peter, Robert

Here is a calibrated DARM spectrum from today's DC-readout lock, using the new CAL-CS channel described in LHO#16698.

According to GWINC, the BNS inspiral range of this spectrum is 8 Mpc.