The setup is:

- Looking at 1720,1665,1667 oh lines as well as HI
- The freq switch is done by using two velocities for the same source: 7.5 AND 58.384 Km/sec
- The interim correlator is used in full stokes mode with 2048 channels over .78125 MHz bandwidth.

- Set 7.5 km vel

- adjust power, doppler shift
- 10 sec calon
- 240sec data

- 10 sec calon
- 240sec data
- set 58.384 km/sec velocity
- doppler shift (we are using velocity to shift the freq rather than a fixed freq freq. so each board gets a different shift)
- The doppler shift includes the source velocity as well as the change in the user projected velocity into the lsr system.
- 10sec calon
- 240sec caloff
- 10 sec calon
- 240sec caloff

- I through together some idl code to look at the data.

- The full processing should eventually be done with carl's
routines.

- find all of the 7.5 km/sec (freqOn) data as well as the 58.3384 km/sec (freqOff) scans
- Use corstokes() to process each scan
- Create calOff by averaging 10 sec of the datascan
- bpc

- compute calDif=calOn-caloff spectra

- then do a linear fit to calDif (exclude edges and lines)
- Use this for the bandpass correction
- phase rotate with caldeflection
- No mueller matrix
correction is applied

- FreqSwitch processing
- Let a set be:
- freqOn,freqOn, freqOff,freqOff .. this is 240secs*4 seconds of data
- process the first freqOn with the first freqOff of each set
and the 2nd freqOn with the 2nd freqOff

- compute fsw1=freqOn - freqOff spectra
- make a copy of fsw (fsw2) and shift it by df=(velOn-velOff)/c * cfrEach band
- do an integral shift
- then do an interpolation for the fraction portion of the shift
- Compute fsw=(fsw1 - fswSh2)*.5
- do a linear fit about the line (excluding the lines) to get rid of standing waves.
- Average fsw over each day.
- currently unit weighting is done (should use 1/sigma^2 eventually)
- There is currently no gain correction (we only have point source gains).
- Average all days done (scale each day by the number of scans that day)

- The plots show the average of 8 days of data (.ps) (.pdf)
- Colors:
- red=stokesI
- green:stokesQ
- blue: stokesU
- black: stokesV
- Units:
- The horizontal scale is lsr km/scal
- The vertical scale is deg Kelvins
- I've left the factor of 2 in (so Tsys is 60 Kelvin, not 30 Kelvin)
- No gain correction has been applied
- the Relative line strength label is the peak line strength
divided by the 1667 Line, and then multiplied by 9.

- Page 1:

- Top: 1720 line
- middle: 1665 line
- bottom: 1667 line
- Page 2:
- A blowup showing the q,u,v power.

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