Attendees: Fred, Yohan, Sasha, Alex, Adam, Gemma, Fab, Ben, Hongli, Tapas, Patricio, Roberto, Sylvain
Not attending: Antoine
Note from Sasha: It is absolutely much better to make simultaneous (multi-wavelength)
extraction catalogs. Associating two independent catalogs for images with substantially different resolutions is a bad idea. Imagine this: a hires image shows 10 cores and a lores image only has one blob in the same place. Arbitrary association of the blob with just one source from the hires image is the worst idea. It is necessary to deblend the blob into 10 cores using the positions known from the hires image. Otherwise, the measurements will be completely wrong by a very large factor. Matching independent catalogs works only in the simplest (not realistic) case when both images resolve all cores.
Comment from Fab: the 1mm and 3mm images have the same angular resolution.
Cleanest for measurement only
Roberto said that the 3mm band should not be used for driving the detection for evolved regions...
comparing the measured values with the truth table.
idea. Much better to use the measurements from a code that gives better accuracy against the truth table of a benchmark and use the other measurement from the second code to assess the total uncertainties of the measured quantities.
However, I don’t think it will get to the accuracy level of being able to run core identification algorithms in images with the free-free subtracted pixel-by-pixel. Rather, it can serve as a map to see where there is significant free-free contamination and estimate the free-free flux in selected areas.
Fabien proposes to use these images as masks (for intermediate regions).
Roberto and Adam say that VLA maps (W51, W43, G351) work better because the emission is optically thin and S/N is larger.
We must investigate if extracting free-free flux at the position of cores is more efficient than measuring 1mm/3mm flux ratios to remove the free-free emission from the thermal dust emission of cores.
Adam and Nathalie said that we need a deep clean on each channel and it is difficult and will take long.
Lee: Pure-continuum image is a dream toward hot cores like those in W43-MM2.
Question: What else?
Necessary data are:
Papers dedicated to individual (or a couple of) regions: