Just to explain what I've been doing in my branch (in the mirage/catalogs directory):Ĭatalog_generator.py - contains code that defines mirage catalog objects (separate objects for each type of catalog), including a function to write out the objects into text files of the appropriate formats so that mirage can use them.Ĭreate_catalogs.py - contains code for generating catalogs based on queries to various databases (2MASS, GAIA, Besancon). That should minimize conflicts when it comes time to merge branches. In either case, I'll hold off on developing any more on my catalog_generator branch until you've finished. We can skip the intermediate step though if I don't need to make any changes after you're done. Then we can merge that into the master branch upstream. If you branch off of my catalog_generator branch and develop in there, then once you're done if I need to make any changes to my functions we can merge your branch back into my catalog_generator branch and I can work in there. This catalogue gives AB magnitudes for the 12 NIRISS filters, so it can be adapted for NIRCam easily but for the Guider some additional thought is needed as to what to do. Third, I have a code to generate a fake galaxy population based on the UDF catalogue produced by Gabe Brammer. This works for reddened sources, but then is limited to objects with 2MASS and WISE photometry. One can do this also for NIRCam filters or for the Guiders, but it then requires at least one extra file of simulated magnitudes to transform.Ī possible alternative would be to use just 2MASS/WISE photometry and interpolate in wavelength to the NIRISS or NIRCam or Guider pivot wavelength values. The one caveat is that I am using a code to transform GAIA DR2 blue/red magnitudes to rough NIRISS magnitudes. All this can be put into mirage, probably fairly easily. There is some cross-matching of positions that is done, although the method is simple and would break down in sufficiently crowded fields because the code does not check that one 2MASS source is not cross-matched to more than one GAIA DR2 source. I have various bits of code to do this type of catalogue generation based on 2MASS, WISE and GAIA DR2 data. This would cut down on the number of catalog files needed. Use filter names as column headers, and have Mirage look for those. We should then think about who to consult as an extra galactic expert in order to get good defaults for also suggested adding the ability for Mirage to ingest catalogs containing magnitudes for multiple filters. suggested that would be able to provide good default values for stars. Perhaps the first step is a function to create a simple point source catalog following some set of defaults (or user inputs) in terms of luminosity function, source density, etc. "Wouldn't it be nice if I could tell Mirage to create a globular cluster catalog rather than having to create one myself."Ĭatalog creation is one of the more time-intensive things that a potential Mirage user will have to do, so it would be nice to have the ability to create catalogs of representative scenes (stellar fields, extragalactic backgrounds, globular cluster).
The motivation behind this was feedback from within the NIRCam team ( with the idea:
Create some functions for catalog generation.
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