Symmetrization Þ dosym = yes Þ Recipe: Rotate image by 180o Subtract from original Clip everything below 2s Subtract clipped image from original Þ Advantage: Input image is smooth like the fitting model Þ Disadvantage: Dilemma of determining the pivot point Þ Dramatic test through simulations will be shown later Initial Parameter Values Þ initparam = yes ("Double-edge sword" i. e. dumb but safe) Þ Recomputed parameters: flux, centroid, sizes, position angles Þ Intensity-weighted centroid is recomputed using minimum area (8 pixels) and multiple thresholds (10s, 5s, 3s, all) Þ Sizes are calculated from an intensity-weighted average radius Þ Position angles are computed using typical formulae Þ Dumb but safe because Metropolis temperatures are extremely, extremely generous e.g. TM (position angle) = 60 and TM(size) = intensity-weighted average radius. Minimum/maximum limits are also very generous e. g. Max(total flux) = 2*estimated flux, min(total flux) = 1! Þ This lack of optimization plays a big role in the time it takes to fit a galaxy ... Þ Write your own !!!!!! Þ mdpar file: 400 (ICF models) 500.0 500.0 1.0 1000.0 1000.0 (total flux) 0.5 0.5 0.0 1.0 1.0 (B/T fraction) 2.5 2.5 0.0 5.0 5.0 (bulge effective r) 0.35 0.35 0.0 0.7 0.7 (bulge ellipticity) 90.0 90.0 -360.0 360.0 180.0 (bulge PA) 2.5 2.5 0.0 5.0 5.0 (disk scale length) 45.0 45.0 0.0 85.0 85.0 (disk inclination) 90.0 90.0 -360.0 360.0 180.0 (disk PA) 0.0 0.0 -1.0 1.0 0.1 (dx) 0.0 0.0 -1.0 1.0 0.1 (dy) 0.0 0.0 0.0 0.0 0.0 (db) 4.0 4.0 4.0 4.0 0.0 (Sersic index)
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