Pumpdown continues.
An attempt was done today to run the system with only the 500 l/s "main" ion pump (valved out the turbo pump), but the "controller" was not able to "keep up."
So we'll continue to use the turbo pump in parallel with the ion pump, we'll keep this configuration until the pressure is low enough for the controller to support the ion pump demand.
 

H0:PEM rename to H1:PEM [WP5153, ECR1500016]

Patrick, Jim, Dave:

The EPICS PEM systems which monitor the weather stations and dust monitors had their channel names changed from the prefix H0:PEM- to H1:PEM-.

The DAQ was stopped and the minute trends were offloaded to a temporary location on the SSD raid. A new blank minute trend area was created. The new H1 INI files were loaded and the DAQ was restarted. Later the NDS servers were configured to serve the offloaded minute trends (in their temporary location). Later they will be migrated from SSD to HDD raids.

The EPICS IOCs for Weather and Dust were modfied and restarted. New H1 targets were created, and safe.snap files moved. MEDM screens were modified.

This WP will remain open to cover the remaining DAQ work which is needed.

End Station SUS/SEI upgrade to RCG2.9.1 [WP5154]

Jeff, Jim, Rolf, Dave:

RCG Tag 2.9.1 was installed on h1build. The following models were upgraded to this tag: h1iopsus[ex,ey], h1iopsei[ex,ey], h1susetm[x,y], h1sustms[x,y], h1hpietm[x,y], h1isietm[x,y]. No DAQ restart was required.

This closes WP5154, future WPs will cover upgrading the rest of H1.

3IFO storage environment monitoring

Richard, Filiburto, Dave, Jim:

The EPICS monitoring system for the LVEA 3IFO storage system was started today. The EPICS channels were added to the DAQ.

J. Kissel, J. Warner

We noticed that the wind / tilt at EX was so large that the peak-to-peak amplitude of tilt as measured by the BRS was surpassing the level at which the BRS's gravitational damper turns on. Since we're trying to get data in these high wind conditions, we've gone to the X end and and turned OFF the gravitational damper from the laptop software.
Will turn on again some time soon when it's less windy.

Waiting to clear these until the OMC is shown to be able to handle the changes.

Again there is some 70urad RX (Pitch) and 15urad RZ (Yaw.)  Look at the SDF Diff Table (attached) to get an ideal of where to steer if alignment is suspect.  Do the Yaw on HEPI though to keep the ISI drive minimal.  I suspect the Pitching HEPI will not directly translate to the ISI.

Today's Maintenance Day started with PSL FSS work.  Unfortunately, they were not able to complete this work, because they spent a good chunk of the day recovering from the FSS attempt.  Due to this work, the PSL PZT Mirror swap was not attempted.  Below is a running tally of work.

• Before 8:00:  Peter K working on FSS Elec (~until 8:30)
• Before 8:00:  Elli/Nutsinee Hartman work ("Adjusting PZT Offset") using ALS (~2hrs)
• 7:30:  Jeff/Andres "measurements & pictures":  path for vac plumbing for dust monitors for another 30in & end stations
• 7:59:  Nutsinee heading to EX to turn on TCS Camera
• 8:10-10:07:   Mike/Fred giving tour (may go out again)
• 8:17:  Richard heading to PSL to give PK an elec box
• 8:40:  Gerardo out to check HAM6 Pump state (may take out Turbo today)
• 8:45:  Richard/Fil working on dewpoint sensors in West Bay/3IFO area
• 8:45:  Fire Dept on-site testing valves at Pump room
• 8:50:  Jeff/Andres heading to Outbuildings
• 9:00:  BRS turned OFF
• 9:08:  Dick RF measurements (for 3-hrs)
• 9:10:  Peter just called to say he'll need atleast 1hr to recover the PSL.
• 9:25:  Cheryl removed pesky MidStation FMCS alarms (which came up as MAJOR alarm for years)
• 9:30:  Cheryl LVEA DustMon#15 settings raised since no longer have chamber open
• 9:45:  Praxair truck onsite
• 9:45:  Jodi in LVEA for 3IFO
• 9:55:  Elllie/Nutsinee going to ISCTEX
• 9:57:  Gerardo/Kyle valving out Turbo at HAM6
• 10:15 Rick/Robert/Kiwamu Mirror Swap
• 10:19 Driver here to pick up pallet
• 11:00 Landry tour EY
• 11:05:  Andres checking exit/emer signs
• 11:06 Patrick doing weather station/dust monitor change
• 2:09  contractor picking up pallets (2nd visit of day)
• 2:16 Rick/Peter taking H1 PSL to Science Mode
• 2:33 Kyle to MY
• 3:30 Jim has the Yarm for ISI TFs until ~7pm
• 3:30 Robert heading out to EY (PEM work?)
• 3:15 ALSX aligned, IR Input aligned & handed over to Commissioners
• 4:06 Jeff/Jim heading to EX to turn off damping software for BRS

A while ago I wrote a script to calculate match gains for the BSC FF to match the ISI L4C's to the HEPI L4C's. This was based on Arnaud's script script to compute the match gains for the sensor correction, in alog 16208. The process was much the same, putting the St1 in 750mhz cps blends, turning off feedforward and sensor correction to the ISI and HEPI. I left the ISI's like that for 10 minutes, then calculated the transfer function between the HEPI and ISI L4C's, and took the average between .1 and .4 hz. The transfer functions all look somewhat like the attached one for the BS. Most match gains were are 1 +/-10%, but ETMY and the BS both had one value that was off by about 20%, X for ETMY, Y for the BS. Gains are installed, I'll get some performance data overnight. The script is in the SEISVN under /BSC-ISI/Common/Misc, it's called BSC_FF_gain_matching. You can see what the results look like by running (with the SEI paths loaded) BSC_FF_gain_matching('H1', 'ITMX', 1113079985, 600) and exchanging 'ITMX' for the other chambers.

Since everyone is done at EX and the winds are a blowing, we turned the BRS on and switch to the Mitt_SC.

J. Kissel, K. Izumi

Using the same model I described yesterday (see LHO aLOG 17847), I've now compared it against
(a) this weekend's measured DARM Open Loop Gain Transfer Functions (OLGTFs), which were taken out to 1 [kHz]:
     2015-04-12 Post UIM / TST Crossover Adjustment, Post HAM6 Vent, ESD Linearization OFF, at 10 [W] input power LHO aLOG 17834
     2015-04-13 Increase of input power to 15 [W], ESD Linearization OFF LHO aLOG 17835
and
(b) The previous measurements shown in LHO aLOG 17847.
They've solidified suspicions of we'd just barely begun to see -- there's definitely some funny business going on:
- We suspect that the frequency dependence of the sensing function (i.e. optical plant) cannot be simply described by a single-pole filter, but it could also be a flaw in model of the actuation frequency dependence.
- The optical gain has significantly reduced from 112e6+/-8% to 75e6+/-4%, even though Evan and Sheila have attempted to compensate for it in the DARM loop digital gain.

In the first attachment, I compare all of the measurements against a model with a fixed cavity pole frequency of 389 [Hz], the number calculated to be the ideal from L1 (see LLO aLOG 15923). 

In the second attachment, I compare all of the measurements against a model where I've adjusted the coupled cavity pole frequency to match the model / measurement discrepancy. 

From the comparison of these two models, one can see several things:
(1) There is a systematic difference in frequency-dependent discrepancy between the earlier, 5-300 [Hz] data and the later, post-HAM6 vent, data. This implies something systematic has changed in the time between 2015-04-06 and 2015-04-12.
(2) In order to fit the discrepancy's frequency dependence, I've had to move the DARM coupled cavity pole down to an unrealistically (??) low 320 [Hz] and 290 [Hz] for the earlier and later data, respectively. The ?? is because I'm not sure what is unrealistic.
(3) I've used the same time delay for *all* of the data sets. The 40 [us] was chosen *after* I'd shifted the coupled-cavity pole frequency down in order to get the phase to be flat as a function of frequency. We have no reason to suspect that the time delay would have changed over these 5 measurements, so I take this to be the residual unknown timing error (*not* the 93 +/- 30 [us] I'd said in the previous log).

There are several things think might be the cause of this (arranged in order of what we think is most likely)
- DARM coupled cavity pole is lower than expected because of SRCL offset, low power recycling gain, or IFO alignment
- ESD / SUS isn't exactly 1/f^2 at high frequency
- Some nasty frequency dependence of the linearization algorithm

Kiwamu's hard at work testing the first suspicion. Stay tuned!

I'm taking advantage of the PSL down to get some measurments on the BSCs. The measurements require high blends, no sensor correction or feedforward on the ISI. Should take 10 minutes. I will return the platforms to operating states when I have enough data.

This seismometer has given us problems for some time: alogs 15510, 14482, 9727.  JeffK may point to others too.

On the attached four plots, there are four successive days, Saturday thru Tuesday at 0100pdt.  The lower left panels are the Coherences between the HAM2 & HAM5 (STS-A & C) and the ITMY (STS2.)  The Upper Left, Upper Right, and Lower Right panels are the ASDs of the X Y & Z DOFs respectively of STS2 A B & C.

The take away is that in general the character of the ITMY (STS2-B) ground seismometer doesn't change like the other two instruments below 100mhz while the HAM2 & HAM5 instruments change more day to day and mostly look like each other.

Details:  The Z DOF is most obvious in that below 50 or 80 mhz, ITMY trends up steeply while the A & C seismos do not.  For the Y DOF, the HAM2 (STS2-B) signal seems to be the outlier but the day to day doesn't follow a patten between the instruments so I ...  The X DOF is pretty good with the A & C instruments tracking each other pretty closely while the B sensor kinda stays at the same power level, mostly.  So, like I say, a Case, maybe.

New tags were created for the IOCs for the Davis weather stations and Met One dust monitors in the projects svn repository:
trunk/epics/iocs/weather/davis/weather_monitor_ii/tags/weather_davis_weather_monitor_ii-1.1.0
trunk/epics/iocs/dust/met_one/227b/tags/dust_met_one_227b_comp_ctrl-1.4.0

There are no branches and tags for the Lighthouse dust monitors. The code was updated in place in the projects svn repository:
trunk/epics/iocs/dust/lighthouse

I created new target directories in /opt/rtcds/lho/h1/target:
h1weathercs, h1weatherex, h1weatherey, h1weathermx, h1weathermy, h1dustdr, h1dustlab, h1dustlvea, h1dustmx, h1dustmy h1dustex, h1dustey, h1dusth1pslanteroom, h1dusth1psllaserroom

Updated medm screens now live in:
/opt/rtcds/userapps/release/pem/h1/medm/weather/
/opt/rtcds/userapps/release/pem/h1/medm/dust/met_one/
/opt/rtcds/userapps/release/pem/h1/medm/dust/lighthouse/
The sitemap was updated to point to these. I still need to commit them to svn.

The following IOCs were stopped and restarted with the new code:
Davis weather stations: h1weathercs, h1weathermx, h1weathermy, h1weatherex, h1weatherey (on h0epics2)
Met One dust monitors: h1dustdr, h1dustlab, h1dustlvea, h1dustey (on h0epics)
Lighthouse dust monitors: h1dusth1pslanteroom, h1dusth1psllaserroom (on the h0dust Windows virtual machine)

h0epics2 had to be updated to mount /opt/rtcds.

I updated the alarm handler configuration file for the dust monitors. I took the opportunity to remove the FORCEPV and HEARTBEATPV channels in this configuration file which were not connecting.

Dave copied over snapshot files from this morning, changed the names from H0 to H1 and ran burtrestores with them.

Jim B. made the changes for the test dust monitor running at end X. I believe he created a h1dusttst directory in /opt/rtcds/lho/h1/target.

I will work on updating the wiki instructions.

R. Savage, J. Oberling, E. Merilh

Work performed on 4/9/2015.

Summary

We are investigating the channels in the PSL MEDM screens to determine what they do and if they do it correctly, and making changes when needed.  We started with the LO MON on the PSL FSS MEDM screen.  It is a monitor of the LO signal used in the PDH locking of the FSS servo.  We found the gain to be set incorrectly to -0.00666, so we changed it to 0.0044033.  We also changed the readout so that it will read 100% when the LO signal is equal to its nominal value (13.86V), >100% when larger and <100% when smaller.

Details

We have begun an effort to go through the more vaguely labeled outputs on the PSL MEDM screens to figure out what exactly they do and if they are doing it right, and making changes when necessary.  We are starting with the FSS, as that is the hot item in PSL land at the moment, with the LO MON readout located at the bottom left of the FSS MEDM screen.  This signal is read in percentage, but no indication what it is a percentage of.

Looking at page 1 of the FSS schematic in D040105-B shows the LO Mon as the output LOM from an ADC 10-4 directional coupler.  A portion of the LO signal (used as part of the PDH locking for the FSS servo) is diverted and output so we can monitor the LO signal.  This LOM is read into EPICS and sent to a filter with the simple math of: output = (signal – offset) * gain.

The offset is set to -22710.0 counts and the gain is -0.00666.   As this is a monitor signal and reported as a percentage, it follows that the LO MON is reporting the percent error of the LO signal as compared to some nominal value: % error = ((signal – nominal)/nominal) * 100.  This nominal value is the offset in the filter, 22710.0 counts (or 13.86V).  The gain is then equal to 100 divided by the nominal value, or 100/22710.0 = 0.0044033; the gain was found to be -0.00666, so it seems the LO MON readout on the FSS MEDM screen has been misreporting the % error of the LO signal.  We therefore changed the filter gain to 0.0044033.

Also, as the MEDM screen does not properly indicate that the LO MON is a % error, we turned off the offset in the filter.  The math is now: output = signal * gain = signal * 100/nominal.  With this change the LO MON readout will now read 100% when the LOM signal is equal to the offset, >100% when larger and <100% when smaller.

Elli, Nutsinee, Patrick

The medm overview was frozen with white numbers. Restarted the computer and it came back. Burtrestored PLC1, PLC2 and PLC3 to 3:10 this morning.

Nutsinee, Elli

To take a measurement with the end-station HWS, the green beam cannot be resonant in the arm cavity.  To take a measurement while the IFO is locked in red, this means we want to add a misalignment offset to one of the ALS_X/Y_PZT1/2 drivers to misalign the green beam in the cavity.  Today we are working out what offset is required to do this.

First we looked at the Y arm.  We looked at what offset we need to add to H1:ALS-Y_PZT2_YAW_MISALIGN_BIAS in order to offset the beam enough that green is both not resonant in the arm but the beam yet not so badly aligned that we see evidence of clipping on the HWS camera.  We put -3250 counts in H1:ALS-Y_PZT2_YAW_MISALIGN_BIAS , requested 'misalign' state for H1:ALS-Y_PZT2_MISALIGN_SWITCH and 'sum' state for H1:ALS-Y_PZT2_MISALIGN_TYPE.  We turned off the input to the filter at  H1:ALS-Y_PZT2_YAW_OUTEN.  This gave us a good image of the ETM on the EX HWS.  Changing the MISALIGN_BIAS by +/- 100 counts made the image on the HWS camera noticabally worse.

When we came in this morning the interferometer was unlocked and trying to lock.  We set ISC_LOCK to down and ALS_YARM and ALS_XARM to unlocked.  We have left the guardian in this state.  I have left the ALS-Y_PZT2 driver in it's nominal 'aligned' state (and the BIAS values have not changed).  When we statred the flashes in the y-arm were about 1.2 counts, indicating good alignment.  After 30mins the flashes were down to 0.8 counts, indicating the alignment had gotten worse.  This suggests the hysteresis in misaligning and realigning these PZTs may noticablly effect the green alignment.

We are planning to do the same thing on the x-arm, although we have not yet gotten to a good alignment with bright flashes in H1:ALS-X_TR_A_LF_OUT this morning.  But we have noticed the end-X HWS camera isn't taking images properly, so we are going to diagnose that now.  We will leave the X-arm alignment as we found it this morning.

Jeff/Andres will be going to EX, so we turned the BRS Switch OFF (with help from TJ & Jim W).  We will turn them back ON when incursions are complete probably after Maintenance since we have winds hovering around 20mph already.

Ross Kennedy & Ed Daw

Instructions for acquiring 100kHz bandwidth ASD, cross correlation, and cross spectral density measurements with 100kHz bandwidth.
1. Check that the LVEA SR785 in the LVEA is hooked up to the OMC DCPD whitening preamplifier pick-off (channel A) and the long RG-58 cable back to the REFL 
electronics (channel B). I left it hooked up when we departed, but it might have been disconnected, I guess. Check also that the GPIB and wireless internet box are connected and powered up.
2. On a control room machine, cd to /ligo/home/controls/edaw_work/hfross
3. Do ./SR785broadscan
- this generates a sequence of measurements covering DC-102.5kHz in 16Hz bins. There are four resulting plots, in order, ASD from the OMCDCPD1, ASD from REFLAIRQ90, cross correlation density from both ports (note that this is per Hz over 16Hz bins, so multiply by 16 to obtain cross correlation on the usual 0-1 scale), PHASE of the cross spectrum
between OMCDCPD1 and REFLAIRQ90 (mainly useful to see the noise in the phase disappear at frequencies where there is extensive cross correlation. 
Results appear in the saved_data subdirectory. Text files of data are saved there too for more detailed information on line frequencies.
Let me or ross know if this doesn't work - we can probably help fix it.