Here is the current status of things in guardian, for people who will be locking latter tonight:

• The violin mode damping is turned off by the coil drivers state, because we found in the past that we couldn't transition the test mass coil drivers with the damping on. As we saw last night, we need to re-engage this for long locks.  This afternoon we tried not turning the violin mode damping on until after doing the coil drivers, but this rung up a mode badly enough to loose lock.  For now I have moved violin mode damping back to 2Watts RF locked. I made the violin state into a state generator, which is used twice, once when we are locked on RF, and again after coil drivers. (The same code gets executed twice).
• In low noise ASC I've added code to turn of the SRM dithers and engage the SRC1P WFS loop, it leaves SRM yaw uncontrolled. This is only partially tested, and starts on line 3488
• NOISE_TUNNINGS can be run as is, but will not engage SRC FF (just type in gain to try it, the nominal value is 1).
• I also added some code to LOW noise ESD ETMY to prevent it from running if the control has already been switched. 

Today I attempted to confirm that the X-end RGA was still functional after having been vented, removed from its protective nipple, re-installed and evacuated yesterday.  I wasn't able to do this due to an inability to connect to it with the RGA-dedicated laptop.  There is some sort of network issue that has been hit or miss for awhile now but, recently, has degraded to the point of being unusable.  I'll try again after investigating and/or at the next window of opportunity.  

Here is the current state of the H1 DAQ.

h1fw0 and h1fw1 have been completely stable for several weeks, and following the code fix on Wednesday 9/7 the frames written by both are 100% identical. These systems have the same hardware and are running the same code, but h1fw0 occasionally asks for retransmissions and h1fw0 never does. The OS install is slightly different between the machines, and we will try cloning fw0 from fw1 next week.

h1fw2 is a front end computer, running U12 with a local disk system for frames. It was running the original daqd code, but went unstable after the Sat 9/10 power outage. We upgraded it to the rcg3.2 daqd this afternoon to see if this improves stability. It is now connected to UPS power.

Now that h1fw2 has the new set of EPICS diagnostics channels I have expanded the DAQ overview medm screen to show these.

State of H1: locking and easilly getting to DC_READOUT

Activities:

• after lunch I locked H1 and went to DC readout, and while H1 was in DC Readout I worked on damping violin modes with some succes
• unfortunately H1 broke lock due to an earthquake
• since then Commissioners have been working on the ISS which included an attempt to improve the qpds with an amplifier box that has whitening gain, but this is on hold
• AC ran a bit after the PSL encursion, sothe room cooled by about 5F and is now recovering

Lisa, Sheila, Ed

Durring ER9, the intensity/jitter noise in DARM was worse than inO1, but not as bad as now.  We looked at the PSL accelerometers, and see that the table is moving about a factor of 5 more over a broad range of frequencies from 150-550 Hz. The coherence of DARM with PSL table acclerometers and the ISS PD is also increased compared to July.  The last panel shows the coherence of the table accelerometer with the ISS PD.  Ed trended PSL pressures, and found that the flow rate durring ER9 was 0.5lpm, compared to 0.7lpm now.

Albert, Chandra

9:00am local

20 sec. to overfill CP3 with 1/2 turn open on bypass LLCV. Left bypass exhaust valve open. Exhaust line is still frosty, but the ice balls near exhaust valve have melted.

CP3 show 'n tell for Albert Lazzarini.

This morning I opened up the ISS photodiode box.  The beam incident into the box is attenuated by a polarising beamsplitter
and half waveplate combination.  The rejected beam is dumped into an absorbing Schott glass filter. (see ISSBeamDump.jpg)

    The power going into the photodiode box was measured to be 597 mW.  For ease of installation I inserted a neutral density
filter labelled "ND=0.3" at the input to the photodiode box. (see NeutralDensityFilter.jpg).  The output of PDA went from
-8.43 +/- 0.07 Vdc to -2.22 +/- 0.01 Vdc, which is somewhat more than one would expect from the label.  The half waveplate
was adjusted to bring the output of PDA to -5.22 +/0 -0.03 Vdc (see BeforeWaveplate.jpg and AfterWaveplate.jpg).

    rpn1.jpg shows the free-running spectra as measured by PDA and PDB after the installation of the neutral density filter.
As previously, both agree quite well.  Attached are a few other recorded spectra with the differences being the gain slider
setting.  The transfer functions for a few gain slider settings were measured (see ISSTF.jpg).

    It is not obvious to me why the in-the-loop noise would increase as the gain increases.  See for example g3.jpg and
g6.jpg.  So this might be an electronics problem?

    Also attached is the power noise as seen by the PDA55 photodiode that monitors the power going into the input modecleaner.
0.307 mV was the output of the photodiode when the ISS was locked.  However it might be that the bandwidth of this photodiode
was only 60 kHz, depending on how the gain selector switch was set.  Beyond about 1.6 kHz, the measurement is limited by the
dark noise of the photodiode.
Click here for the datasheet for this obsolete photodiode from Thorlabs

Photos of photodiodes removed from damage OMC. Photos taken by GariLynn B. at Caltech.

Photos have been posted on E1600268-v1, "Initial Inspection of OMC Bench at CIT Aug 2016"

https://dcc.ligo.org/LIGO-E1600268

Naming conventions are from E1600262-v3, "aLIGO OMC: Spare OMC production plan"

https://dcc.ligo.org/LIGO-E1600262

Diode pictures attached to this alog entry:

• Diode DCPD1 - image (diode1.jpg, 147.6 kB)
• Diode DCPD2 - image (diode2.jpg, 133.5 kB)
• Diode QPD1 - image (diode4.jpg, 706.8 kB)
• Diode QPD2 - image (diode3.jpg, 92.9 kB)

• I put BRS to Very Windy this morning after the meeting
• JimW is modifying guardian to incorporate stage2 code 
• current state is Earthquake v3, which also has the BRS not in use
• will switch back to Windy when the site is clear

It seems that since the last power glitches, the DBB is back to operational status... hmmmm. That is to say, before the power glitches it was unusable due to the mysterious tripping of the (dbb) interlock when trying to open the beam path into the box. In the past week I've been trying to get good measurements. This was a abit daunting due to the ISS 3rd loop work that was breaking the IMC lock consistently and yanking on the LASER frequency. Below is what I could muster over the course of a couple of days. ISS_RPN will come later as Peter is currently in the enclosure and working on it.

Comments:

RPN - 35W path looks suspiciously good accross the spectrum by a factor af a few...hmmm?   200W path looks tyo be below requirement from 2Hz to ~25Hz and then above to about a factor of a few through high(er) frequencies.

FRQ -  35W path is quite noisy at low freq (below 15Hz). Other than that the rest looks good save for the usual resonances. 200W path looks ok across the spectrum except for the usual resonances.

PNT - 35W path pointing looks pretty good. 200W path shows seperation  of the 1x/y and 2x/y  by a factor of a couple.

MSC - 35W path shows TEM 20 +02 an order of magnitude higer than reference. 200W path shows TEM 02+02 mode higher by a factor of a couple.

Morning Meeting:

• SEI - all good
• SUS - Betsy to LVEA for about an hour
• CDS/Electronics - waiting for changes in PSL
• PSL - Peter is putting a ND filter in front of the ISS inner loop
• Commissioners left a alog 
• VAC - Chandra - take visitor to EX around 9:30 for les than an hour
• VAC - visiting CP3 this morning
• VAC - Kyle at EX this morning for about 20
• VAC - JimW - will modify to restart automatically

FRS:  reviewed

Currently:  no locking with Peter in the PSL modifying the ISS beam path

Tonight there was a flurry of activity with H1.  There were issues with locking at the beginning of the shift, but it got better....we had a range reminiscent of H1 during S6:  19Mpc!  :)  Slowly but surely, we're gettin' there.

Locking Notes:

At the beginning of the shift, had issues locking ALS.  This was traced down to the wrong polarizations.  

• Adjusted polarazitaion for Y-arm PLL.  Also had VCO guardian error message, so it was RESET.
• Also had same issue with X-arm, so did both of above.
• Before getting to DC_READOUT, Guardian had an issue with ENGAGE_SRC_ASC.  Jamie & Jenne troubleshooted the issue and finally got guardian going again.
• While at DC Readout:  Chris & crew(s) ran some measurements.
• Had a nice 2.5hr long high power lock.  Terra chased some PIs.  Kiwamu & Sheila eventually took us to nearly 20Mpc, and then we lost lock.
• While reacquiring, the ETMx was off a bit, but eventually got it back.
• DRMI looked off in yaw & dead.  PRMI looked ugly, too.  So, we misaligned PRM & adjusted the BS (in yaw).  This got us partly there.  Then Sheila had me restore the PRM & then tweak it such that we had decent PRMI flashes.  Eventually locked up and had no issues getting up to 50W.  (Oh, we did need to employ the BS excitation trick that Sheila alogged about on Tues night.
• Kiwamu, Sheila, & Matt will now tinker with a 50W H1....whoops, it just broke lock...time to sneak out!  :)

FOM Note on Nuc5:

Cheryl mentioned this was booted during the day, and then it died & no DMT Viewer/DTT came up on their own.  I rebooted nuc5 and conversely to last night, the DMT seismic trends looked fine & current.

Matt, Terra

Status of PI after TCS work and ring heater change transient (for at least the first three hours of 50 W lock):

1. Successfully damping all modes (with some caveats; see #4,5.)
2. Actively damping ITMX 15520, ITMY 14980 and 15515, ETMX 15541 and 15008, ETMY 15542, 15009, 18041 and 18059 Hz. Of these, the 18kHz and 15kHz only ring up during the transient. 
3. All modes are now getting damped using the PLL. One motivation for this is avoiding saturations. I'm fairly certain that the mysterious sign flips and illogical behavior when increasing gain in the past have been due to something saturating along the loop, usually resulting in ringing up the mode. 
4. 15009 Hz (MODE 26) is still a bit confusing: it rings up twice during the transient period and appears to require a sign flip to damp each time. I'm not yet convinced this isn't just a byproduct of the transient though (we flip a gain sign and see a slow downturn on the same timescale as the transient passing, attributing the turn around to the wrong reason?). 
5. After ~2 hours, 15541/2 Hz (MODE 17/25) ring up. While we have the actuation strength to damp these, these modes are ~.5 Hz apart, so the PLL is having trouble staying on the right one and I had to do lots of actively jumping back and forth between controls. We are going to try sending both drive signals to both optics, etc. 

3 hours into the lock and all PI's are stable. Leaving PI control with Matt for the night. 

WP 6087

The GDS software has been updated to branch 2.17.4 to address Bugzilla 897, 936, and 952.  Release notes (T1600007) document has been updated.  This affects Ubuntu 12 and Ubuntu 14 workstations.