Following up on the work to replace the "dripless" quick-connect fittings in the 35-W amplifier in the PSL FrontEnd laser, see Link, today I installed the new fittings in one of the spare FrontEnd lasers.

These fittings accommodate 8 mm O.D., 6 mm I.D., tubing from the outside and transition to the 6 mm O.D., 4 mm I.D. tubing that is connected to the crystal holders in the laser head.

The installation proceeded as expected and confirms that this scheme should work for the laser currently operating in the H1 PSL. We plan to do the same fitting swap in the H1 laser room next monday.

Photos are in the attached .pdf file.

While we were sitting here with the interferometer locked and no commissioning activities related to SR3, the SR3 SD osem glitched and cause the damping loop to saturate the DAC.  The interferometer stayed locked. 

During O2, we had simlar glitches which caused locklosses.  32328

[PeterF, StefanB, Craig, Jenne]

We tried several different levels of RF9 modulation depth.  More than nominal is definitely bad, less than nominal (nominal during acquisition) doesn't seem to do a lot in DARM.  Colors should be consistent across plots, eg. ref 18 is brown is -6dB from nominal for all the attached plots.  Stefan has some more plots that he'll post showing correlations (or not) with various other channels.

13:30 UTC Chris S. opening inner 'High Bay' rollup. Also working on scaffold at HAM6.
15:25 UTC Chris S. done in LVEA
16:00 UTC ISI CONFIG is in LARGE_EQ_NOBRSXY
16:03 UTC ISI CONFIG to WINDY
16:04 UTC Ran RECOVER EQ
16:06 UTC Rerequested WINDY
16:15 UTC SEI back. IMC_LOCK reports 'IMC WFS not centered'.
16:18 UTC Starting initial alignment.
16:35 - 17:07 UTC Jeff B. to LVEA, staging for vent
16:45 UTC Aidan updating HWS code
16:45 UTC Karen and Vanessa to LVEA, end stations
16:46 - 16:51 UTC Nutsinee to HAM6
16:59 UTC Nutsinee transitioning LVEA to laser hazard
17:07 UTC Jeff B. to end Y
17:09 UTC Karen and Vanessa leaving end Y, going to end X
17:10 UTC Nutsinee done transitioning LVEA to laser hazard
17:10 UTC Richard, Filiberto to ISC racks by PSL
17:10 - 17:24 UTC Betsy and Jason to HAM6
17:14 UTC Daniel S. done installing chassis
17:26 UTC Karen and Vanessa leaving end X
17:28 UTC Filiberto back
17:34 UTC Karen and Vanessa to LVEA, cleaning
17:35 UTC Jeff B. back
18:21 - 19:09 UTC Daniel V. to LVEA, turning on OSA
18:22 UTC Terry and Nutsinee to ISCT6
18:25 - 18:44 UTC Charlie to LVEA to inspect scaffolding
20:06 UTC Chandra, Kyle, Gerardo back from CER, HAM6, checking HV procedure for vent
21:25 UTC Kyle to HAM6
21:25 UTC Robert to HAM6
21:25 UTC Richard to CER
22:06 UTC Robert back
22:06 - 22:54 UTC Kyle to mid Y
22:09 UTC High dust alarm at end Y DM 1. Ran dust monitor check. All report OK.
22:56 - 23:00 UTC Bubba to HAM6
23:42 - 00:06 UTC Robert to end Y to modify ESD voltage monitor
23:59 UTC Terry back

Here is another noise budget update, with measurements taken over the last several days.  The main difference between this and 45036 is the improvements in the MICH and SRCL feedforward (45110), and I have updated some of the ASC injections. 

The third attachment shows the noise budget sum compared to the DCPD cross corelation this morning:

This is based on only 5 minutes of data, because I was trying to avoid glitches and times when there are injections. At high frequencies, we don't have frequency noise included in the noise budget yet, which could explain part of the discrepancy between the cross corelation and the noise budget sum at high frequencies.  At low frequencies we don't know what this noise is, but there are some peaks on a smooth background. 

[Sheila, Terry, Haocun]

Fiber arrangement:

• The patch panel with sleeves of CLF and Green path was moved to the left side of the table.
• The on-table fiber was changed to 5m ones for both green (Thorlabs P3-460P-FC-5) and CLF (Fabrice).
• The temporary fiber arrangement from HAM6 to ISCT6 for green: orignal 6m + new Thorlabs 2m as a shield. This part will be changed to a new 5m Thorlabs P3-460P-FC-5 on Monday together with the new feedthrough.

Feedthrough and Mode Matching Solution:

• I double-checked the mode matching for feedthrough SN7 using Fabrice's Measurements.
• SN7 Mode: waist radius = 156um @ 0.36m out from fiber coupler. The same solution can be used, reaching an overlap of 98.5%.
• SN2 will be a back-up option, which was a prototype.

4 Irises were placed on ISCT6 for alignment references.

Here is a good reference time for Lisa:

2018/11/09 21:31:50 UTC (6220013528), reported at 80Mpc

I've started the process of offloading the last 5 months of raw minute trend data (3.1TB) from h1tw0's SSD raid to h1ldasgw0:/trend-0 spinning media (compressed ZFS file system on SATA-BOY raid). The entire copy-and-verify process takes about 3 days.

Since h1nds0 is not the default NDS for the control room, I'll skip the exporting of these data from their temporary location while the offloading is progressing.

RGA scans at vertex/corner and EY in preparation for vents next week. Filaments on both RGAs are now off.

In prep for opening the HAM6 End cap door Monday morning, the following things have been prepped:

1) Removed Illuminator housing from door - guillotine and yellow cover are in place

2) Removed Camera housing from door - guillotine an yellow cover are in place

3) Large 16' cleanroom has been moved ~2 feet East (as far as it can) to make room at door opening end

4) Scaffolding has been erected around chamber corners and top for working at height (pictures are of partial assembly mid build yesterday)

Fil Marc Daniel

We modified the spare CM board (s/n S1102622) according to E1800338 and swapped it with the existing one (s/n S1102621). This modification includes low pass filters for the DAQ readbacks, and a frequency change in the first two boost stages to 10Hz/500Hz.

On Tuesday access to the LHO LDAS web servers (eg ldas-jobs.ligo-wa.caltech.edu) were updated to no longer require authentication from the LHO control room workstations.

I put the lockloss triggering into the guardian, such that the PREP_FOR_LOCKING state will force it to be triggered, so we can acquire lock.  Then in DRMI_TO_POP, at the same place that the individual LSC filter banks were getting their lockloss triggers set, I set the IFO trigger to look at LSC-POP_A_DC.  We have had one lockloss with the triggering active, and the next lock had much smaller violin modes. 

When we engaged the violin damping after we hit resonance while still locked on RF, the narrow-band ETMY mode 1 violin almost immediately rang up.  So, we need to be doing a clear history on those before we start locking.  Most of our usual-width filters have step responses a few tens of seconds, but this narrow band one has a step response greater than 3000 seconds.  So, when we relock and turn on that damping (since we aren't doing a clear history right now) that filter still has the lockloss transient in its memory. 

I've now added turning off the inputs and clearing the violin mode histories to the guardian.  The inputs get turned back on in the violin damping Settings state.  We've got an EQ incoming, so I don't think we'll get a chance to see this keep the modes down tonight.

Here is a comparison between the signals at the LSC-REFL_A servo now and 3 days ago. The filter for the ASC-POP quads made huge difference in the frequency range from 10Hz to 100Hz. The rms is about a factor of 2 lower due to the microseismic. This might explain the drop in RF power at this detector reported in alog 45100.

Craig, Peter, Stefan

We remeasured and turned on the MICH and SRCL feed-forward. In particular, we
 - Moved all violin notches to the MICH and SRCL filter banks
 - Moved the AC coupling to 0.1Hz (in FM2 of MICHFF and SRCLFF1 FM2) so its phase influence is small.
 - Moved all feed-back top the ETMX.
 - remeasured the transfer functions and fitted the filters (in FM3 of MICHFF and SRCLFF1 FM3).
 - Updated Guardian to engage them.

Attached are the MICH and SRCL OUT to DARM transfer function with and without the feed forward engaged. For MICH we get about x100 suppression, for SRCL about x50.

I've found that after yesterday's maintenance, REFL_A_RF9 RF monitor got significantly smaller and more stable at the same time.

Attached left is a trend before the change. In 20W lock the RF level (CH5) was going all over the place between -18 and -8 dBm.

In the middle is a trend after the change (now) in 20W lock. After an initial hike associated with powerin up, it quenched down to about -17dBm on average and the fluctuation is much smaller than before.

To the right is the spectrum comparison of RF9_I and Q, red is now and the green is before. A small part of the RF level change could be attributed to the smaller micro seismic motion, but RMS is only a factor of 1.5 or so smaller now than before.

Interestingly, a broad bump (10-70Hz or so) that was present in REFL_A_RF9_Q as well as POP_A_RF9_I  is gone now. But that isn't good enough to explain the RF level change either, something should have been going on out of band.

Could this be somehow related to the change of CM-MC board connection cable from TNC-coax to 2-pin lemo twisted pair and/or the limiter (alog 45046)?

Craig is heading to the floor to redo the RF measurement (old measurement: alog 44811).