The current QA2 method creates sharp discontinuities in some regions between pixels with good fits (where the full NH3 windows are used in the moment maps) and pixels without good fits (where a window around the main component at the mean cloud velocity is used in the moment maps). The rms of the mom0 map is consequently not smooth due to the large variation in the number of channels used in the integrated intensity calculation.
Suggested improvements:
use the good fits in the region around pixels without good fits to better estimate the local vlsr to set the windows used for the moment calculation
use the full windows for the NH3 hyperfine components for pixels without good fits, shifted to match the above vlsr
This will necessarily increase the rms noise in the moment 0 maps, but I think will produce a more accurate representation of the gas structure and our data. The discontinuities are also an issue for any sort of structure analysis based on the moment maps.
The current QA2 method creates sharp discontinuities in some regions between pixels with good fits (where the full NH3 windows are used in the moment maps) and pixels without good fits (where a window around the main component at the mean cloud velocity is used in the moment maps). The rms of the mom0 map is consequently not smooth due to the large variation in the number of channels used in the integrated intensity calculation. Suggested improvements:
This will necessarily increase the rms noise in the moment 0 maps, but I think will produce a more accurate representation of the gas structure and our data. The discontinuities are also an issue for any sort of structure analysis based on the moment maps.