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Page history last edited by weiguang 9 years ago

Weiguang (simulator):

- processes of producing observational images:

     1. luminosity/magnitude/spectrum for each star particle (using its age, metallicity and mass) is produced by the ezgal package with BC03 SPS model. This software also provide both observer and rest frame results.

     2. the luminosity/magnitude/spectrum is assigned to a 2D mesh, with pixel size depended on its redshift (list below). The assignment can be the common Nearest Grid Point(NGP), CIC, TSC, or more fancy SPH smoothing depended on your choice. 

     3. this 2D mesh is saved into a fits file. If there are multiply bands (for luminosity/magnitude), they will be saved into different data blocks. I will try to make a statement at the header. Spectrum is 3D array, where the first 2D is the projected mesh, the third dimension is the spectrum within that pixel. The wavelength for the spectrum is saved in a second data block.


Here is an example (from ~/ClustersOfGalaxies/PerthClusters2015/users/wcui/MAP/Lum_zXXXX_obs.fits):

NGP, pixel size 5.0, ks band(with g, i, r band saved in later blocks), 




Please have a look at the file and let me know what do you suggest?


Chris (observer):
- Observing ~1” pixel resolution (2kpc at z~0.1) make that softening length.
- z=0.05, (1”=1kpc), z=0.1 (1”=2kpc), z=0.5 (1”=6kpc; 2kpc=0.3”), z=1.0 (1”=8kpc, 2kpc=0.2”), z=1.5 (1”=8.5kpc, 2kpc=0.2)
- Need image at wavelength of observation
- want erg/s/cm^2 per pixel in observed waveband (K, g, r, i) in fits file
- THEN Chris to apply known zero point
- For observed Ks band, SDSS gri bands
- Over 5’x5’ = 2.5*2.5 Mpc at z~1.




Just some fun attempts fitting some profiles to some mock data (Sersic: n=4, re=30kpc, m0=2.) m0 is in arbitrary units, and errors 0.3/sqrt(m)


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