andres.ramirez@LIGO.ORG - posted 13:12, Tuesday 04 February 2014 (9808)
Entering the LVEA (West Bay) for ACB work - Mitchell/Scott
h1nds1 was rebooted to clear a situation where it appeared that both h1fw0:/trend and h1fw1:/trend were mounted to the same /trend mount point.
Conlog is now using the channels in /ligo/lho/data/conlog/h1/target_grep_channel_list.txt (attached). This file contains 96,957 channels. Conlog is currently not connecting to 3,416 of them.
The list of unconnected channels is attached.
A set of TF was ran overnight on the ETMY after some test-stand alignment, to check for rubbing. Measurements were succesfull and are not showing any signs of rubbing for both chains.
Attached are the comparison with the model for the main (1st pdf) and reaction chain (2nd pdf).
Looking at the time delay as measured by the timing system:
| Station | Round-trip delay(µs) | One-way delay (µs) | |
| Corner-EX | 43.0 | 21.5 | |
| Corner-EY | 43.4 | 21.7 | |
Looked at the QPD Transimpedance Amplifier units at EX, S1102832 and S1102821. We wanted to confirm the board versions. All boards D1001974 are version 2 and have the following configuration: - C15 is removed - R15 is 0 ohms - JP1 has a jumper installed Filiberto Clara
Sorry, I was wrong, but things still look dubious.
From the attached dark spectra of QPD segments, TR_A needs digital dewhite, it doesn't look like TR_B has too much dewhite.
But TR_B still looks like it has some kind of problem, maybe white/dewhite mismatch for seg3 and seg4 (or seg1 and seg2). Needs to be checked later.
FYI, IAS:
Below is the table of the ETM and ITM bias slider offset when the arm was aligned. Xarm data is right after we saw some green fringing (https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=9064). I'm taking HIFO-Y data for Y arm (https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=6627) even though HIFO-Y was more than a year after H2 EY was pumped down, as the slider was not calibrated during OAT, the data channels were all H2 so it's hard to track it down using data viewer now, and I don't know how much the output matrix changed (the uncalibrated slider data is still available e.g. here: https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=3363).
| EX | IX | EY | IY | |
| PIT urad | 332.5 | 82.8 | -142.7 | 247.5 |
| YAW urad | -3.75 | -55.5 | 197 | -271.5 |
Though EX, IX and IY all needed to be pointed down, EY needed to be pointed up (the slider sign convention is such that a positive PIT offset points the optic down).
Slider calibration is probably 15%-ish good or maybe better based on the measurement of baffle PD positions.
OTOH, the earth radius is about 6400km. The angle between the local vertical of EX and the corner is about 4km/6400km=630urad.
The relation between the gloabl and local coordinate system is defined in T980044.
Again FYI:
We know from the excercise of offloading TMS PIT to HEPI, and then offloading HEPI PIT back to TMS, that the PIT of HEPI doesn't affect the PIT of ETMX much.
The default nds server is now h1nds0. We will be performing maintenance on h1nds1 over the next couple of days.
A new version of gds software has been installed, addressing the following issues: 299, 328, 389, 428 - Any combination of start, stop, and BW that result in an fft of 512 points fails, due to how the fftw library is used by diag. Fix by changing the way the fftw plan is generated, specifying FFTW_MEASURE instead of FFTW_ESTIMATE. 497 - Add option to foton to allow specifying a SFM name along with a filter file name. See foton man page for details on the "-s" option. 500 - Removed Kaiser Window option from diaggui, it was never implemented. 511 - Changed foton to report that no design string exists for a filter if that is the case. Previously this was reported as a different misleading problem. 519 - Allow IP broadcast for awg, tp discovery to be specified by an environment variable (LIGO_RT_BCAST) instead of assuming the broadcast address of the workstations. All these changes have been built from gds/branch/gds-2.16.9. This affects Linux and Mac OS X workstations. Existing diag or diaggui sessions should continue to work using the older software, but at some point we need to make network switch modifications that will cause the older software to stop working. Advanced warning will be given.
Laser Status: SysStat is good Output power is 29.3 W (should be around 30 W) FRONTEND WATCH is Active HPO WATCH is red PMC: It has been locked 6 day, 16 hr 34 minutes (should be days/weeks) Reflected power is 1.1 Watts and PowerSum = 12.1 Watts. (Reflected Power should be <= 10% of PowerSum) FSS: It has been locked for 1 h and 6 min (should be days/weeks) Threshold on transmitted photo-detector PD = 0.74V (should be 0.9V) ISS: The diffracted power is around 6.7% (should be 5-15%) Last saturation event was 22 h and 26 minutes ago (should be days/weeks)
Work completed.
Looking at QPD amplifier chassis.
He is back. Work Completed.
While searching for a flash of IR in TMSX IR QPDs, TR_B looked like it has a very slow low pass filter (attached).
The difference between TR_A and TR_B in the digital world is that the dewhitening (40:0.4) for the fixed whitening is off for TR_A and on for TR_B.
So it seems as if these IR QPDs are without fixed (non-switchable) whitening, but we're supposed to have these.
Later Filiberto will go to EX, open the chassis and change the jumper to get the whitening back.
Update: https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=9792
Evan, Kiwamu, Stefan Tonight we left the PRMI locked, with a dither loop for ITMY, and a sqrt(POB18) gain scaling for MICH and PRC. The ring heater was set at 0.75W for both upper and lower heater (total of 1.5W). The heat was turned on at 09:13:38 UTC. The idea of this "low-heat" run is to keep the heating in a regime where the lens strength is roughly linear in the change in build-up. This should give us a good measurement of the lens-strength vs. time.
Here's the time evolution of the defocus of the test mass (single pass, thermal lens only, two different x-axis ranges) in response to a 1W step function in ring heater power at t=0s.
