I recentered the beam on WFS_A of IMC because the beam was found to be off from the diode by a couple of mm horizontally. Probably I accidentally bumped a steering mirror when I was working on the GigE cameras on IOT2L. And indeed, no other photodiodes showed such a big off-centering. Due to this WFS_A without the beam on its diode, IMC ASC kept unlocking IMC. After the centering, IMC ASC came back to normal. IMC seems stable.

Also, I noticed that the whitening gain for both WFS_A and B was set at 45 dB which should be 36 dB according to this alog (alog 9094). So I set them back to 36 dB.

Kiwamu, Sheila

We locked the X arm.  We started with Keita's alingment, adjusted the ITM a little bit until we saw some fringing.  At the end station we adjusted the demod phase watching Imon (photo of switch positions on phase shifter is attached), then tweaked the ITM alignment again.  We tried moving the ETM around but found that Keita's alignment was pretty much the best we could find.  This means in the end we had 

Once we had the PLL locked we locked the PDH easily (In 1 pol negative, -4dB in1 gain, common comp and the first boost on, and the slow option on (meaning no slow feedback).  REFL PD B dropped from 18000 counts unlocked to around 16000 counts when we were locked on the carrier.   We measured a transfer function (last attachment), the ugf was roughly 8kHz.  

Last we checked ISCT1 for a beam, but didn't find anything there.  

There is currrently 5.8mW on the refl PD A this signal is not showing up in the fast digital system, neiher the beckhoff readback nor the fast system readbacks are working for this channel right now.  

Refl B has 1.4mW of green aligned onto it REFL_B_LF_OUTPUT is 15500 right now and beckhoff is reading 4.6V.  The hardware switch on this is currently set to 20dB. 

I also aligned the QPD and plugged X (which is vertical the way the qpd is mounted) into ISC extra Analog input 1, Y (horizontal) into analog input 2, and the sum into analog input 3.  right now there is 6.2mW on the QPD, resulting in 4.7 V on sum, and roughly zeroed in X and Y.  

References:

• https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=9064
• https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=9087

This is an update of the above alog entries. After turning off the isolation loop for EX ISI, I started the initial alignment of the TMS, ITMX and ETMX again.

This was done by pointing TMS to ITM arm cavity baffle diodes PD1 and PD4 (note that for ITM baffle PD4 is connected to PD3, so the actual channel I looked at was H1:AOS-ETMX_BAFFLEPD_3_POWER), take note of the TMSX alignment slider values, set the TMS slider to the mean of PD1 and PD4, then align ITMX to point the beam to ETMX baffle diodes etc.

The bias sliders are calibrated using 4000m arm length and the vertical/horizontal distance between the PDs.

In the table below, (P, Y) refers to the alignment slider values for each optic,  "Aligned" is the mean of PD1 and PD4

Note that HEPI still has 12000 counts RY offset to relieve TMSX PIT which is due to 300urad systematic in ETMX.

Turning End X ISI isolation loop on (which was declared to be the default state of ETMX ISI) makes ALS beam move too much. It's so bad that, by the time the beam comes from TMS to ITMX to ETMX to ITM baffle diode, the beam motion is larger than the beam radius.

After fighting with it for a few hours I concluded that we cannot do anything useful with it, so I turned it off and left it as damping only.

Don't turn on the isolation. If you think you have a better isolation filter, you need to coordinate with integration team to find a good time slot for testing.

Valved-in IP1,2,5, and 6*Dumped GV7's unpumped gate annulus volume into pump cart*Valved-out YBM turbo*Opened GV7*Valved-in IP12*Dumped GV20's unpumped gate annulus volume into pump cart*Valved-out X-end turbo*opened GV20*Dumped GV5's unpumped gate annulus volume into pump cart*Opened GV5

Andres R. & Jeff B. 

   After replacing the metal EQ Stops with the silica tip in chamber EQ stops, we installed the glass mass in H1-SR2. The mass is now suspended on a new wire loop. The measured pitch and roll of the M1, M2, and M3 masses are almost zero, (as close to zero as we can measure with an optical level). 

Per the XYZ Local CS document for H1-SR2 (D0901128) the center of the optics, including the spacer (D1100180), should be at 220.9mm above the ISI table. The measured height of the center of the M3 optics in H1-SR2 is 221.28mm above the ISI. As it is hanging, the center of the optic is 0.38mm high, which is within the +- 1mm tolerance for the center of the mass. 

Tomorrow we will center the OSEMs and start running transfer functions. 

M3 measurement data: 
Measured height of top of M3 mass = 215.7mm
Measured height of bottom of M3 mass = 64.79mm     
Center of M3 mass -->(215.7 – 64.79)/ 2 = 75.46mm 
Height of center of mass --> 64.79 + 75.46 = 140.25mm
Adjustment for spacer --> 140.25 + 81.03 = 221.28mm 
Height of beam path with spacer = 220.9mm
Mass height to beam path differential --> 221.28 – 220.9 = 0.38mm 

- Richard M added water to the PSL Chiller
- Planning to open GV-20 and GV-07 for commissioning work
- OptLev transmitter pylon setting at EX
- SR2 metal mass hanging
- Fiber pulling at EY
- CDS rebooted the timing system and all FEs
- Rick restarted the PSL
- Mitch working on ACB in LVEA West Bay

After Rick restarted the PSL this morning, I saw that the PMC trans read back on the mddm screen is 3Watts, when it should be more like 10Watts.  It doesn't seem like the power has actually dropped, since the ref cab trans, ISS PDs and the periscope bottom mirror trans PD are all approximately the same as they have been.  The attached screenshot shows that the signal from this PD dropped on Dec 22nd, although the power on the ISS PD did not drop.  Kiwamu previously investigated a similar issue (alog 8622 ) and the readout came back to normal after he disconnected and reconnected the lemo connector to the PD.  

It seems like we have either a bad cable or a bad connector on the table that needs to be replaced. 

I also added a link to the PMC trans power filter bank on the PMC medm screen.  

We opened the LVEA to the X arm beam tube today in preparation for HIFO X operation.

Prior to opening valves the LVEA was pumped by one main turbo pump only. Pressure in this state was 6.3 e-7 torr (pt 170B on the X manifold)

At ~ 9:30 pacific time Kyle valved in 4 main ion pumps and isolated the turbo, then at 10:06 he opened GV7 to expose CP2(xarm).

Later in the day at 2:40 he opened GV5 to expose CP1 on the yarm.

Pressure is still falling but is currently at 5 e-8 torr (pt 170B).

So, in summary, moving from one turbo to ion pumps and 80K pumps has given us > a factor of 10 improvement in pressure.

Kyle is adjusting ion pump settings to further improve things as several pumps are not operating correctly.

See attached - 24 hours plotted.

I restarted the PSL this morning after what was apparently a shutdown initiated by the front end watchdog.

The Beckhoff status screen showed "Power error (WD)" in red and the trends show the NPROOK and WATCHDOG channels triggering at the same time (16 Hz resolution).

The second plot attached below shows the front end output power over the past 100 days.  The steady decrease in power is at a rate of about 6-7 percent per 100 days.

I recall that the threshold for the watchdog to trip is a 10% change in power from the time the watchdog was set.  It this is correct, then it doesn't appear that the watchdog should have tripped due to the slow decrease in the output power.

I will investigate further with the PSL team.

Today at 10:40 we shut down the MSR UPS (Work Permit 4366). On power up its commication error did clear for a while, but then returned.

The main impact on CDS uses was:

• loss of the timing master
• operator workstation and alarm handler machine lost power
• name servers were shutdown, preventing operator station reboot
• the GC virual server for alog, svn, bugzilla was glitched and stopped running

The biggest impact was the loss of the timing system, which required all front ends and their IO Chassis to be power cycled. The sequence followed was:

• power down front end computer (hard shutdown, no need to worry about Dolphin glitching)
• flip switch OFF on front of IO Chassis
• remove 24V DC power cord from rear of IO Chassis, then reattach
• flip switch ON on front of IO Chassis
• verify timing slave is operating correctly (1Hz led flash)
• power on all front end computers

All systems burt restored to their safe.snap settings. I manually restored the PSL models to the settings as of Noon Saturday 4th January.

With Jonathan on phone support, we rebooted the GC machine and Jonathan restored the services (see Jonathan's alog)

We power cycled all the front ends in the DTS. The staging building test stands were already powered down for the holidays and stay off. The LVEA test stand systems have been powered down for some time while those systems are moth-balled until needed again.

The aLOG was down for a short while today. This happened after the UPS power cycled in order to clear some communication glitches. The power did not properly switch over on the systems from UPS to system power.

I will likely take the aLOG down tomorrow during the maintenance window to try and reproduce and diagnose this problem.

This also affected the SVN server and the bugzilla a server.

I made some edits to the IMC guardian over the weekend.  I added some error checking to IFO_IMC. 

There is an error check function, in acquire if the IMC is not locked the errors are checked, if any of them are problems a message is written to the log, and the guardian enters the error state.  Jamie is going to find a wway to make these messages appear in a more prominent way, but for now we shoud look in the log whenever the guardian is in the Error state. 

This seemed to be working on saturday afternoon.  Occasionally (although not every time) the guardian fails with an error message:

User warning ca.get('H1:SUS-MC2_M3_WDMON_STATE') timed out after 1.00 seconds

File: ligo/apps/linux-x86_64/cdsutils/lib/python2.7/site-packages/ezca.py, line 194, read

raise EzcaError: could not get value from channel H1:SUS-MC2_M3_WDMON_STATE

Less than 3 hours after getting it damped.  Seems like too long a time to be an instability but who knows.  Attached is 30 minutes of the T240 before tripping.  Seems like an abrupt railing spike, not a building and continuing EQ surface wave.  Anyway there isn't a timely EQ for this one.  The SUS didn't trip and neither did HEPI; got to figure out the WD scheme.  Seems like this ISI has never survived more than a few hours....  I'll put it in lvl1 and see how it does this morning.

So ETMx ISI is in lvl1 isolation at ~0800pst.

Wasn't watching the process as I've done this a few times but the SUS tripped for the first time triggering the SEI ISI and HEPI.  Painful cause this has the large pitch offset to tilt the TMS down to the corner.  I've got it back damped (SUS w/ Kiwamu's help) and the HEPI tilted and the ISI in lvl2.

Running Transfer Functions on ITMx and ETMx – Hugh
Optical Lever electronics work  at End x – Thomas
Demo board repair on ISC PSL Racks – Aaron
Cryo baffle assembly  End Y – Mitchell/Gerardo

I activated unit-1, unit-2 is now "resting".

Overnight TF's on ITMX HEPI were mostly succesful, but it looks like we have an issue with instrument pods, or associated rack chassis in one of the corners. All of the IPS's and L4C's in corner 3 on this chamber look bad. Power spectra also don't look great.

Andres R. & Jeff B.

   We suspended H1-SR2 with the metal dummy mass installed. Checked several of the critical measurements to make sure nothing was disturbed during the transport of the suspension to the LVEA. All measurements are within specifications. 

   We centered the BOSEMs and took a set of transfer functions for phase 1b testing.
 
   The TF plots are attached below. There is some noise below 1Hz. However, as we are going to swap out the bottom wires, the M3 mass, and rework the suspension anyway, spending much time tracking down and fixing this noise is not a high priority.