Step 4: Add two channels and make a strain frame file

• For the initialization and running the pipeline, please refer step1

• Access frame cache file by specifying frame_cache and instrument as in step2

• Define a frame multiplexer(mux) to write channels into a frame as in step3

• Add CH1(MICH_DELTA_TM) and CH2(MICH_RESIDUAL) and output into ADD divided by the arm length to convert into the strain

   1 arm_length  = 3000
   2 
   3 ch1 = pp.mktee(pipeline, pipe_dict["CH1"])
   4 ch2 = pp.mktee(pipeline, pipe_dict["CH2"])
   5 add = cp.mkadder(pipeline, cp.list_srcs(pipeline, [ch1, short_queue],\
   6                                                   [ch2,  long_queue]))
   7 add = pp.mkaudioamplify(pipeline, add, 1./arm_length)  # Divide by arm length   
   8 
   9 keys.append("ADD")
  10 pipe_dict["CH1"] = ch1
  11 pipe_dict["CH2"] = ch2
  12 pipe_dict["ADD"] = add

• The python script is available at git repository

> kagra-cal/Observation/Phase1/tutorials/adder --help
Usage: adder [options]

Options:
  -h, --help            show this help message and exit
  --cache=cache         Set the name of the LAL cache listing the frame files
  --gps-start-time=seconds
                        Set the start time of the segment to analyze in GPS
                        seconds.
  --gps-end-time=seconds
                        Set the end time of the segment to analyze in GPS
                        seconds.
  --ifo=name            Name of the IFO (default= K1)
  --channel=name        Set channel name(s) to extract (default= CAL-
                        CS_PROC_MICH_DELTA_TM_DQ,CAL-CS_PROC_MICH_RESIDUAL_DQ
                        ,CAL-CS_PROC_C00_STRAIN_DQ)
  --frame-type=name     Set the frame type as input to the frame writing
                        element. (Default=TEST)
  --output-path=name    Set the output path for writing frame files.
                        (Default=.)
  --format=format       Set input channel(s) format (default= F64LE)
  --ch-rate=rate        Set input channel data rate (default= 16384)
  --frame-duration=seconds
                        Set the number of seconds for each frame. (Default =
                        32)

• This is an example to add two channels (CH1:MICH_DELTA_TM and CH2:MICH_RESIDUAL) and output into a new channel (ADD) and write into a new frame file (it should be OK to ignore the warnings)

> kagra-cal/Observation/Phase1/tutorials/adder --cache=k1.cache
GPS:  1209288320 1209288352
seeking GPS start and stop times ...
setting pipeline state to playing ...
set to playing successfully
running pipeline ...

(python:655): GStreamer-WARNING **: gstpad.c:5079:store_sticky_event:<framecppchannelmux0:src> Sticky event misordering, got 'segment' before 'stream-start'

(python:655): GStreamer-WARNING **: gstpad.c:5079:store_sticky_event:<progress_sink_K1:src> Sticky event misordering, got 'segment' before 'stream-start'

(python:655): GStreamer-WARNING **: gstpad.c:5079:store_sticky_event:<sink:proxypad0> Sticky event misordering, got 'segment' before 'stream-start'

(python:655): GStreamer-WARNING **: gstpad.c:5079:store_sticky_event:<multifilesink:sink> Sticky event misordering, got 'segment' before 'stream-start'

(python:655): GStreamer-WARNING **: gstpad.c:5079:store_sticky_event:<framecppfilesink0:sink> Sticky event misordering, got 'segment' before 'stream-start'

(python:655): GStreamer-WARNING **: gstpad.c:5079:store_sticky_event:<progress_sink_K1:sink> Sticky event misordering, got 'segment' before 'stream-start'
progress_src_CH3 (00:00:00): 1209288352 / 32 seconds (3779026100.0 %)
progress_src_CH1 (00:00:00): 1209288352 / 32 seconds (3779026100.0 %)
progress_src_CH2 (00:00:00): 1209288352 / 32 seconds (3779026100.0 %)
progress_sink_K1 (00:00:10): 1209288320 seconds
progress_sink_K1 (00:00:10): 1209288352 / 32 seconds (3779026100.0 %)

• Check the contents of the output frame file

> $LAL_PREFIX/bin/framecpp_query --list proc K-TEST-1209288320-32.gwf                                                                         Frame Version: 8 Frame Library: frameCPP Library Revision: 1 Originator: IGWD
Frame Offset: 0
K1:CALIB_ADD
K1:CALIB_CH1
K1:CALIB_CH2
K1:CALIB_CH3

• Comparison between PROC_C00_STRAIN (renamed as CALIB_CH3) and MICH_DELTA_TM+MICH_RESIDUAL (renamed as CALIB_ADD)

> kagra-cal/Observation/Phase1/tutorials/trf --frame K-TEST-1209288320-32.gwf --channel=CALIB_ADD,CALIB_CH3 --output=trf.png
Channels: K1:CALIB_ADD K1:CALIB_CH3

• (Next) Step 5: Demodulate a calibration line

• (Prev) Step 3: Extract channels and make a new frame file

• Tutorials