H1CALCS Model Updated to Include EPICs Records for Reference Time Calibration Filters at Cal Line Frequencies

J. Kissel, D. Barker, J. Batch, J. Betzwieser

As the calibration group solidifies how to measure the slowly-time-dependent parameters of the aLIGO detector's DARM loop, we've identified that we can no longer just get away with only comparing the real-and-imaginary parts of the current DARM Open Loop Gain transfer function against those of a reference time -- at calibration line frequencies -- to produce a "gamma" coefficient (a real, scalar, multiplicative factor applied to the detector's strain output). Because of charge on the test mass evolving with time (on the actuation side of things) and the DARM coupled cavity pole frequency evolving with time (on the sensing side of things), we now must at least track, if not correct for time-varying optical gain, cavity pole frequency, and actuation strength. As such we've parametrized the interferometer response (see T1500377), and this parametrization needs the real and imaginary parts of the actuation function, sensing function, and DARM filter -- again at calibration line frequencies -- for the reference times. 

Long story short, I've added EPICs records to the CAL-CS front-end model to store these new real-and-imaginary parts to the actuation function, sensing function, and DARM filter. The new channels are
    H1:CAL-CS_TDEP_${ACTTYPE}_LINE${NUM}_REF_A_REAL
    H1:CAL-CS_TDEP_${ACTTYPE}_LINE${NUM}_REF_A_IMAG
    H1:CAL-CS_TDEP_${ACTTYPE}_LINE${NUM}_REF_D_REAL
    H1:CAL-CS_TDEP_${ACTTYPE}_LINE${NUM}_REF_D_IMAG
    H1:CAL-CS_TDEP_${ACTTYPE}_LINE${NUM}_REF_C_REAL
    H1:CAL-CS_TDEP_${ACTTYPE}_LINE${NUM}_REF_C_IMAG
    H1:CAL-CS_TDEP_${ACTTYPE}_LINE${NUM}_REF_C_NOCAVPOLE_REAL
    H1:CAL-CS_TDEP_${ACTTYPE}_LINE${NUM}_REF_C_NOCAVPOLE_IMAG
where
${ACTTYPE} = ESD, PCALX, or PCALY
${NUM} = 1, 2, (3, or 4)
and there are 4 lines for ESD and 2 lines for each PCAL.

I will update the CAL-CS MEDM screens with a look-up table for these reference values tomorrow and/or over the weekend.

Short story long again, I ran into two problems trying to compile the changes that I wanted to make:
(1) Not sure how bast to describe this bug, but it comes up when you use several FROM and GOTO tags on multiple levels of subsystems without connecting them to a CDS part on each level. There were two examples of me doing this in my desired CAL-CS model, where I'd tagged a signal, traversed down a subsystem level, tagged it again, and traversed down a few more subsystem levels before it connected to a filter bank. I show the two ways I had done this schematically below:

CASE 1:

IPC part --------+
                 | CAL_CS_MASTER
                 +----------------+
                                  | TIMEDEPENDENCE
                                  +---< TAG 1 |      | TAG 2 >---+
                                                                 | ESD_LINE1
                                                                 +---+
                                                                     | DEMOD
                                                                     +---+
                                                                         | DEMOD
                                                                         +----------- filter bank

CASE 2:
                  +---< TAG 1 |      | TAG 1 >---+
             DARM |                              | TIMEDEP
filter bank  -----+                              +--- < TAG 2 |      | TAG 2 >---+
                                                                                 | PCALX_LINE1
                                                                                 +---+
                                                                                     | DEMOD
                                                                                     +------------ filter bank

I'm not sure which of these two caused the problem, but he attached screen shots with the file tag "doesnotcompile" demonstrate what I *wanted* to compile. The correspondingly named screenshots *without* any extra file tag shows what we had to do in order to get the model to compile. Pretty darn ugly.

(2) The original "doesnotcompile" name for the PCAL and ESD line calculations were stuck in a subsystem I'd called TIMEDEPEDNENCE. Sadly, this totaly blew my channel character limit out of the water. This is a known feature that one can only have channels of 60 characters or less, I had just forgotten, and also didn't appreciate how many sub-sub-sub systems there were in this block. As such, I've reduced the sub system to the obfuscated "TDEP." Oh well.