Jeff K, Dave B, Darkhan T,

Overview

Coherence calculation settings were updated today's after a minor bug fix in CAL-CS.

We discovered that some of the reference EPICS records that are used for calculation of kappas in the front-end were not set (or lost after a DAQ restart). The records were populated with values calculated from the DARM model for ER9.

Details

• Today we modified CAL-CS synchronized oscillator demodulation for DARM_LINE1 to include an ability to set a desired phase (LHO alogs 29852, 29853). After this update the replica of the DARM_LINE1 excitation, used for calculation of time-dependent parameters ("kappas"), uses SINGAIN and COSGAIN settings of the synchronized oscillator (which weren't set before). Both of these gains must be set to be the same as CLKGAIN.

Similarly, SUS_LINE1 synched oscillator SINGAIN and COSGAIN values must be set to be $(IFO):SUS-ETMY_L3_CAL_LINE_CLKGAIN multiplied by DAQ downsampling TF magnitude at this frequency (35.9 Hz at LHO). Synched OSC phase must be set to the DAQ downsampling TF phase at the line frequency (not sure if we need to put positive or negative phase). Previously SUS_LINE1 synched OSC parameters were not set properly and the coherence was not calculated (see attachment 4, coherences calculated during last 4 days).

Both DARM_LINE1 and SUS_LINE1 oscillator parameters were updated, the changes were accepted in SDF_OVERVIEW.

• We updated the EPICS records that are used for calculation of κ_c and f_c, H1:CAL-CS_TDEP_PCALY_LINE2_REF_A_USUM_(REAL|IMAG) and H1:CAL-CS_TDEP_CAVITY_POLE_PCAL_FREQ:

Old : H1:CAL-CS_TDEP_PCALY_LINE2_REF_A_USUM_REAL 0
New : H1:CAL-CS_TDEP_PCALY_LINE2_REF_A_USUM_REAL -1.73852e-19

Old : H1:CAL-CS_TDEP_PCALY_LINE2_REF_A_USUM_IMAG 0
New : H1:CAL-CS_TDEP_PCALY_LINE2_REF_A_USUM_IMAG -1.03541e-19

• The oscillator phase field was added to the MEDM screen CAL_CS_TDEP_DARM_LINE and some minor fixes were made to the CAL_CS_TDEP_OVERVIEW screen. The changes were committed to cds_user_apps repo, r14297.