08:00 resarted Alarm Handlers; CDS overview: noticed some conflicting counts on fw1 and some timing flags at the mid station; Vacuum: noticed IP-01 flashing red. Sent out emails to the corresponding folks for a check-out.

08:30 ISS loop coming in and out of saturation. Diffracted power all over the place. I bumped the refsignal up a click and the diff power stabilized. I tried a series of clicks following and got the diff power back up to ~7.6%  

09:09 Betsy and Travis out to West bay to work on 3IFO Quad.

09:10 Andres out to W Bay

09:20 Peter F out to LVEA

09:55 J Bartlett, also Andres out of LVEA

10:25 Ryan reported a possible network outage lasting ~10 minutes maybe upstream of PM&L

? Alastair putting power meter on TCS X arm table (WP 4925)

11:12 Robert working in beamtube between mid Y and end Y (shaking tests)

11:21 Dan to end X to look for equipment

11:56 Shivaraj to end X and end Y to mount magnetometers on tripods

12:38 ISS first loop went erratic again until ~

13:19 Karen at end Y

13:51 Karen out of end Y

14:30 Dan H out to HAM6

15:20 Rana brought to my attention folks entering VEA areas. Not everyone is reporting their desire to enter to the operator. Cleaning personell are calling after they've arrived at end stations.

As a first step towards a fast shutter at the AS port, I swapped the QPD transimpedance amplifier box for ASC-AS_C for one with the SUM output spigots for the shutter input.  From rack R5 slot 20:

Out: S1102836

In: S1301506

I also changed the P3 jumper on the OMC PZT LV driver board to the correct position (across pins 2 & 3).  Now, a 0V input to the 'shutter logic' input on the front of the OMC PZT driver box is recognized as a 'fault' condition (i.e., with 0V input, the PZT shutter function is triggered).  This draws the PZT1 drive down to 0V (from 10V).  It also pretty well disables the dither output to PZT1, so no OMC locking until we connect the PZT shutter input to a 5V supply (like, for example, the shutter logic controller on top of ISCT6).

It looks like the ASC-AS_C sum is about the same as before the swap, but we probably need to redo the dark offsets.

J. Kissel, R. Abbott

Was checking the status of the ETMX optical lever against Doug's status report (see LHO aLOG 14711) before I took some measurements using it, and found that the ETMX optical lever's compensation filters (i.e. H1:SUS-ETMX_L3_OPLEV_SEG?) have to filters, "gain2" and "gain1.4" (which are gains of 0.5 and 0.707, respectively) that are turned ON. I couldn't find any aLOGs about these filters, and it doesn't really make sense to me to compensate for any analog gain, given that we normalize by the SUM.

Anyone know anything about this?


%%%%%%%%%% EDIT %%%%%%%%%%%
Doug's status chart reports values exactly backwards and bit-shifted up 1. "HIGH" bits are LO, and "B1" = B0. The confusion arised from Evan's convention for high vs. low, and that the switches are numbered starting at 0 on the board, and 1 right next to the switch. Therefore, the ETMX is compensated for correctly. 

Will post corrected assessment shortly.


%%%%%%%%%% Historical Log, for future reference %%%%%%%%%%%%%

Piecing together the puzzle, from Doug's aLOG (LHO aLOG 14711), and the various circuit schematics (Configuration Daughter Board D1001631, Chassis Assembly, ), Evan's recent PR3 tune up (LHO aLOG 14631), my aLOG from many moons ago (LHO aLOG 3619), and a phone call to R. Abbott, I can determine that having each channel in the following configuration (as indicated by Doug's aLOG, where B0-B7 is the configuration for the first channel, and the remaining 3 channels, B8-B15, B16-B23, and B24-31 are in the same configuration),
Switch     Function       Setting    Status
 Name                     HI   LO   
  B0      G = 24 [dB]           X      ON
  B1      G = 12 [dB]           X      ON
  B2      G = 6  [dB]      X           OFF
  B3      G = 3  [dB]      X           OFF
  B4      1:10 Whitening        X      ON
  B5      1:10 Whitening   X           OFF
  B6      1:10 Whitening        X      ON
  B7      Latch                 X      ON
Note -- and this seems to be a common misconception -- when the switch is LO (or "0", or away from the chassis as installed) the switch is ON / ENGAGED. Therefore, the total transfer function: G = 36 [dB], two stages of (1:10) whitening.

(filter zero and pole notation is (z:p) -- note that the poles and zeros is INCORRECT [i.e. inverted] in my old aLOG)

Thus, the current compensation scheme, with FM1 (10:1) with FM4 and 5 (the "gain" filters mentioned above), it seems as though the switches have been interpreted in exactly the opposite fashion as the schematic intends. Even worse -- the LATCH is ON, which means it's actually telling the board to engage whatever the settings were *before* the latch were engaged, and the current status of the bits B0 through B7 DON'T MATTER. #facepalm

Will get with Rana / Evan / Doug / Jason about this.

Measured power output of X-arm laser to be 56.3W directly after laser.  Thermopile in laser has a lower V/W sensitivity (0.116V/W) than others measured. I've updated the calibration to reflect this so that the channel H1:TCS-ITMX_CO2_LSRPWR_HD_PD_OUTPUT now gives correct laser output power.

I have also redone the calibration of the rotation stage using a second power meter on the table at the output to the CP.  The rotation stage position for a minimum output was correctly set at (37 degrees) giving a zero reading on a 100W and 10W power meter heads (we can go to a more sensitive power meter also, but here I'm measuring the full range of the rotation stage).  Maximum is seen at 82 degrees giving 5.44W.

Attached is a plot of angle to power for both power meters.

I've checked the calibration of the rotation stage, which was almost correct, and have slightly altered the maximum power output setting for this.  Minimum power and minumum power angle were both correct.

It looks like we are seeing the rotation stage not always going to exactly the requested angle.  This results in non-zero power output when minumum power is requested.  This is not an issue with the power meter - it is real.  So when there is a non-zero power reading on the power meter it means there is power going to the CP.  Repeated presses of the 'Go to minimum power' button result in the rotation stage eventually going to the correct angle.  If it still won't go to zero, then using the 'Home' button can reset the rotation stage position.

• exist but are not on the MEDM screen
• are on the MEDM screen but do not exist

Observing the many trips HAM2 has experienced using the guardian recently, I've seen that after the first group of dofs are isolating, the remaining dof error points often grow large and when these dofs gains are ramped up, the ISI trips with a rung up GS13.  I saw that the guardian was loading the reference locations between the dof groups engagement.  Whereas the old seismic command scripts would only load the reference locations after all the dofs are isolating at the free hanging position.  Remember, the command script was not having any trouble turning the isolation back on.

Jamie modified the Guardian to do the loading of the reference location at the end of the isolation process like the command scripts.  When I got my window to test this, I actually forgot at first to restart the guardian.  And, the first couple times guardian was able to bring it up!  When I realized it wasn't doing it the new way, I remembered the restart, but I kept trying the guardian.  On the third or fourth attempt with the guardian it tripped.  I then restarted the guardian and then the guardian was successful at full isolation at least 6 times before the commissioners returned to the control room.

So again, my theory is, when the isolation loops are servoing to a place away from the free hanging position, the uncontrolled dofs error points can grow large.  This is dependent on many thing and lots of luck good & bad.  When the loop is engaged at low gain, the error point may be swinging about zero and if the loop gain is changed to 1.0 (from 0.01) at an unlucky time, bam goes the GS13.

Currently, HAM2 ISI is successfully back under Guardian conrol.

Keith T, Jim, Daniel, Dave

As Keith mentioned in yesterday's CDS meeting, the RFM IPC error rate at the SUS model is related to the CPU usage of the LSC sender. To show this, I've attached a minute trend plot of the past 7 months of IPC error rates at SUS-EX, along with the CPU-MAX of the LSC model. As can be seen, when the LSC CPU-MAX is regularly around 40uS, the receive error rate goes up from 2 to 10 errors per 16384 received packets.

At 10 errors per 16384 packets, the error rate is 0.06%. Can we determine if this is significant?

questions/ideas which have been mentioned when thinking about possible solutions:

ISS first loop was all over the place as was the diffracted power at the beginning of my shift.  A slight tweak in the less negative direction set it back to stable. Further adjustment got it back to ~7:5% diff power at 2.04V refsignal. Perhaps more attention can be given to ISS on a daily basis by the operator on shift until a better solution can be implemented. 

https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=13781

Based on the TCSX central heating calibration (62.3 micro-diopters single-pass per Watt) and the calculated static lens of -80213m, we require:

+201mW of central heating on ITMX to correct this static lens.

Edited 31-Oct-2014: this isn't correct because of an error in the laser power calibration

Daniel, Dave

We have stopped the following CSD guardian nodes from running. They can be restarted at a future date if needed.

If we choose to restart these, they should be generically renamed (dropping the H1 in the name)

K. Venkateswara

I've attached ASD and coherence plots from 40k seconds of data from BRS/T240 and the super sensor from last night. Wind speeds were in the 5-10 mph range. This time, I showed the raw signals coming out from BRS and the T240 X instead of showing the output of the filters. I've also shown the ref. mirror and the output of the super-sensor.

BRS has much larger noise below 2-3 mHz, than the T240, even though the sensor noise appears to be much less. It was interesting to me that it had a similar shape as the ref. mirror output and there does appear to be some coherence between the two. Temperature is the usual suspect at these frequencies. A sensitive temperature sensor on the BRS platform would be useful in diagnosing this noise.

The current cdsutils installation (r361) has a new and improved NDS avg() function.  The previous version was buggy, was calculating the standard deviation incorrectly,  and had a clunky interface.  This new version fixes those issues:

fixes to standard deviation calculation

The standard deviation was previously being calculated incorrectly and the returned values were wrong (off by some unknown but kind of large factor).  The new version uses the python numpy.var() function to calculate the variance, from which the standard deviation is calculated.  It has been verified to be correct.

channel IFO prefixes no longer need to be specified

Previously, the avg() function required full channel names, with IFO prefixes.  This new version works like the ezca interface whereby the IFO prefix can be left off of the channel name.  This makes things much cleaner, and allows scripts to be portable.  E.g., instead of:

cdsutils.avg(2, IFO+':LSC-DARM_OUT')

just do:

cdsutils.avg(2, 'LSC-DARM_OUT')

new format for returned values

Probably the thing that's going to cause the most trouble is that the interface to the function has been fixed up.  Previously, the function was returning a dictionary of channel:avg key pairs.  This was very clunky to use.

The return value of the function now mirrors the input argument.  So for instance, if a single channel is requested, a single avg value is returned.  If a list of channels is requested, a list of average values is returned, in the same order as the input channel list.  So calls like:

avg = cdsutils.avg(2, 'LSC-DARM_OUT').values()[0]

can now just be:

avg = cdsutils.avg(2, 'LSC-DARM_OUT')

If the stddev option is provided, the output will be an (avg, stddev) tuple, or if multiple channels is requested, a list of such tuples, e.g.:

avg, stddev = cdsutils.avg(2, 'LSC-DARM_OUT', True)

I have fixed all calls to cdsutil.avg() that I could find in the USERAPPS/release.  I likely didn't catch everything, though, so be aware of the new interface and update your code appropriately.

After the recent upgrades, a couple of small bugs were identified in guardian and cdsutils, and new versions were pushed out:

• guardian r1102: fix bug is reload with NodeManagers, guardctrl allow restarting stopped nodes, new log viewer (see below)
• cdsutils r361: fix bugs in new avg() function (see followup log)

The new version have been pushed, and some of the guardian nodes have been restarted, but not all.  We should restart all nodes at the next opportunity.

New log viewer

I pushed out a new guardian node log viewing interface, so that you no longer need to ever type in a password when viewing logs.  This new interface can be used by using the new guardlog program that is now installed everywhere.  Just provide as arguments to the program the names of the nodes whose logs you would like to view, e.g.:

guardlog SEI_ITMY HPI_ITMY ISI_ITMY_ST1 ISI_ITMY_ST2

The logs of all specified nodes will be tailed, interleved as they are spit out, to the current terminal.  The GUARD medm control interfaces now use this log viewer as well.

tl;dr: A very lightweight "guardlog" server is now running on the guardian machine (h1guardian0), listening on port 5555.  Making a simple TCP connection to that port (with the guardlog client) will open up the interface and spit out the logs for the specified nodes.

J. Kissel

Another data point on the issue of IPC timing causing errors between the LSC model and QUAD models -- Stuart and I added 1 (one) RFM IPC sender to the LSC and 1 (one) RFM PC receiver to each of the ETM models for DARM-sensed, violin mode damping on Tuesday morning (see LHO aLOG 14657). This appears to have increased the ETM model's CPU_METER by ~1 [us], and made no change to the random-time computation time jumps up by as much as ~5-6 [us]. Surprisingly, it *decreased* the LSC model's average compute time by ~ 1 [us], but again also did not affect the timing jumps as high as an extra 7-9 [us].

I attach a 7 day, minute trend. The only discrete jump in the trend is when the models were restarted around 2014-10-28 14:15 UTC (or Tuesday 2014-10-28 07:15 PDT).

I noticed that the DARM Error damping display on the QUAD MEDM Overview screen was showing the incorrect channel information. So I substituted them for the correct channels (H1:SUS-ITMY_L2_DAMP_MODE1_OUTPUT, H1:SUS-ITMY_L2_DAMP_MODE2_OUTPUT etc.) and committed the fixed screen to the userapps svn, as follows:-

/opt/rtcds/userapps/release/sus/common/medm/quad/
M        SUS_CUST_QUAD_OVERVIEW.adl

This will need to be svn'd up at LLO too.

The 4.5 hour heating test last night on ITMX was successful. The initial thermal lens transient is shown in the attached plot.

The thermal lens forms relatively rapidly in response to the CO2 heating. Then it decays at the same rate when the heating is turned off. Once again, Physics works.

When the offset in the spherical power at t = 0s is accounted for, the thermal lens magnitude is approximately 80 micro-diopters (double-passed) for 680mW of applied CO2 laser power.

Further analysis on the shape and centering of the lens is pending ...

(The noise in the HWS measurement in the last half hour is coming from SUS injections into ITMX).

As requested by the seismic team,  I ran the script to configure the ETMX ISI to a test configuration at around 1:47:00 in UTC or 18:47:00 in PDT. I am leaving it in this configuration.

Alexa, Kiwamu,

In response to Keita's alog about the PR2 baffle, we took a peek at the PR2 baffle by opening some of the viewports on HAM3 and HAM2 spool.

Conclusions:

• The aperture hole on the baffle looks centered.
• The baffle in front of PR2 looks the right one.

(PR2 baffle check out)

We opened up a viewport on the East side of HAM3 which the leftmost one with an illuminator attached on. This was the only available viewport to open up. We removed the illuminator and looked at the baffle through the viewport. We confirmed that there was no cross bar structure on the side of the baffle unit as shown in the DCC document (D1000328). We could not see the top part of the baffle where it supposed to have a cross bar structure. We took some pictures and I attach them to this entry.

(Peek at the aperture position)

Then we tried a different zooming in the PR2 digital camera in order to have a better view so that we can determine if the aperture hole is in the middle of the baffle unit or not. With a help of flash light illuminating the PR2 baffle from the HAM2 East side viewport, we could clearly see the edge on both right and left sides of the unit as well as the edge of the aperture. It looked like the hole is centered with respect to the right and left edges of the unit. We took several pictures of it via the digital camera so that one can evaluate the position later if necessary.

(MC2 scraper baffle check out)

Then we opened up another viewport on the West side of HAM3 in order to see both MC2 and PR2 baffles. Though, the MC2 baffle was completely occulting the PR2 baffle and therefore we could not see it. We could still confirm that the MC2 baffle has a cross bar structure on the side as shown in the design document (D1000327).