TestCaseData/2009-09-23_bandpass_variations

Description

EmilLenc? did some exploration of how much the CABB bandpass changes during an observing session (12h).

Data Set(s)

• 2009-06-16_1842.C911
• 2009-06-16_2210.C911
• 2009-06-17_0139.C911
• 2009-06-17_0507.C911

Source of interest: 0537-441 Frequency: 6 & 3 cm

We observed

• ripple across the amplitude spectrum, the slope of the spectrum changed with time.
• phase across the bandpass is roughly linear, but slope changed with time (+/- 8deg over 12h).
• the majority of the (amplitude) variation was due to poor calibration - the mean amplitude jumped quite a bit from one scan to the next

The source is actually resolved so the bandpass variations are probably mostly the result of source structure. This data set was mainly of use to build the plotvis application.

Tickets

• ticket:90 is relevant but Emil did not use the updated code in his tests. In this case (resolved source) allowing the bandpass to be time-variable may create confusion about what the correct bandpass calibration is.

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TestCaseData
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