It turns out that the bandpass at the offset frequencies are not necessarily a good match the bandpass at the source frequency. This is unfortunate. When applying the bandpass correction to the phase calibrator, we should see a flat slope. However, we don't. Here are some possible ways of fixing it (if it's a big problem):

- apply to the phase cal and smooth (smooth 7 30 0 -> boxcar smoothing of 30 channels?), or fit a lower-order polynomial to the bandpass (2-3 order)

- can we bootstrap fluxes from B-configuration?

- can we use self-cal?

- see if phase calibrator fluxes have changed over the past year: ie, "proposal" to check fluxes of phase cals

- our line is narrow but so is our band - what is the slope across our line and do we care? A 5% slope or less is probably okay.

- flatten the HI data and see?

To save the smoothed, vector-averaged, calibrated possm spectrum: set outtex.

We will want a saved version of the smoothed bandpass calibrator to estimate this effect.

-- AdrienneStilp - 2009-02-26
Topic revision: r1 - 2009-02-26, AdrienneStilp
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