Attached are the weak heating curves from tonight.

Ring heater turned on: 09:13:39 UTC  (2014/02/04), with a POP18 of about 4050cts
Lensing maximum occurs at 11:31 with an error of about +-5min , with a POP18 of about 7850cts

I.e. the turn-on to peak-lensing time interval is 2h:28min, or about 8880sec.

For later reference, the POP18, 33min into the run was about 4450cts


We will leave the heater on today (at 1.5Watt total) to the long-term equilibrium lensing. From that we can establish the time during initial heating which has the same lensing as the long-term equilibrium. This will allow us to simplify setting the power.

See also alogs
https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=9778
https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=9736

As reference, in alog 9736 we had
Start heating 08:09 UTC and 3500 cts PP18 build-up
Ideal matching at 08:42 UTC, with 11500cts POP18 build-up.
That's 0h33min into the run (1980sec). That was with 20W total.


Based on these numbers I would expect a heating power of 1.5

Work Completed

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.

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:

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

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).

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.

Looking at QPD amplifier chassis.

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.

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.