Calibration of wrong Tsys
Posted: Tue May 16, 2017 3:19 pm
Hi~
In c3086 we were using 6a array to observe the 21cm absorption lines towards LMC/SMC. Some sources were observed in more than one day.
0540-6718, for example, was observed in 161123, 170419, 170426, 170427 and 170430. While in 3 of these 5 days, the amplitude of sources looks to be separated to two values. Take 170427 as example, it looks like this: Plotting all the stokes: 1934-638 from the same day has a similar problem: Is this caused by wrong Tsys measurements? If so how to correct it?
I've tried attsys but it seems not helping much. If attsys is the right tool, how to use it correctly?
Thank you!!
Boyang Liu
In c3086 we were using 6a array to observe the 21cm absorption lines towards LMC/SMC. Some sources were observed in more than one day.
0540-6718, for example, was observed in 161123, 170419, 170426, 170427 and 170430. While in 3 of these 5 days, the amplitude of sources looks to be separated to two values. Take 170427 as example, it looks like this: Plotting all the stokes: 1934-638 from the same day has a similar problem: Is this caused by wrong Tsys measurements? If so how to correct it?
I've tried attsys but it seems not helping much. If attsys is the right tool, how to use it correctly?
Thank you!!
Boyang Liu