aLIGO LHO Logbook

H1 CAL (CAL, ISC)

jeffrey.kissel@LIGO.ORG - posted 13:23, Tuesday 11 April 2017 - last comment - 13:40, Tuesday 11 April 2017(35474)

Time-dependent SRC Detuning Infrastructure Installed, To Be Commissioned

J. Kissel, A. Viets
WP #6572
ECR E1700121
II 7828

Because I'm not sure how long it'll take to make the MED screens and fully commission the new parts' settings until we have results, I just want to get an aLOG in there that confirms we've installed the front-end infrastructure changes to begin tracking the SRC detuning as a function of time.

This required modifying 
/opt/rtcds/userapps/release/cal/common/models/CAL_CS_MASTER.mdl
to include many new EPICs records that store various DARM loop model component values at the already-existing PCAL line frequency (7.93 Hz), and as a bonus, I also installed all of the infrastructure to compute the SRC detuning frequency in the front-end as well -- it was an easy extension of the existing software to calculate the optical gain and cavity pole frequency, following the math in T1700106 and LHO aLOG 35105.

I've installed values for these new EPICs records using svn up'd versions of
/ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/O2/H1/Scripts/CAL_EPICS/writeH1_CAL_EPICS.m
/ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/O2/Common/Scripts/CAL_EPICS/writeO2_TDEP_EPICS.m
/ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/O2/DARMmodel/Scripts/computeEPICS.m

To do/aLOG:
 - Take screen shots of the new model infrstructure to show the implementation
 - Update TDEP MEDM overview screen to include the new math
 - Install demodulation parameters and lowpass filters for new 7.93 Hz demod
 - Install low-passes on F_S and Q_S output banks
 - Compare against GDS pipeline output

Comments related to this report

aaron.viets@LIGO.ORG - 13:40, Tuesday 11 April 2017 (35476)

Link

After an update to the frame broadcaster channel list and a minor correction to the write-EPICS code, we have restarted the primary and redundant calibration pipelines. The restart was at GPS second 1175976351. We can confirm whether the SRC detuning parameter algorithm is working once we have a lock stretch. For information on the new filters, see:
https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=35462
For information on the new gstlal-calibration code release, see https://bugs.ligo.org/redmine/issues/5440
In addition, there are two small improvements I've noted:
1) The latency is reduced from ~12s to ~7s.
2) The CPU usage is reduced from ~55% to ~45%