Changes between Version 9 and Version 10 of psphot_extended_source_fit_20130712
- Timestamp:
- Sep 9, 2013, 11:23:30 AM (13 years ago)
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psphot_extended_source_fit_20130712
v9 v10 10 10 11 11 === Sersic Index === 12 If we look at the sersic index for all galaxies we get the following histogram. The hisogram on the right shows the counts for pure disks and bulges. We see that the fits for bulges are clustered around 4 as expected while disks mostly have values near 1.12 If we look at the sersic index for all galaxies we get the following histogram. The hisogram on the right shows the counts for pure disks and bulges. 13 13 14 14 [[Image(sersic_index_20130712.jpg)]] [[Image(sersic_index_20130712_pure.jpg)]] … … 16 16 === Sersic Fit Magnitudes === 17 17 18 The difference between the simulated galax ys' magnitudes and the sersic fit magnitudes are shown in the following plot. 91% of the sources are contained in the band near zero. The reason for the other bands needs to be investigated.18 The difference between the simulated galaxies' magnitudes and the sersic fit magnitudes are shown in the following plot. 19 19 20 20 [[Image(dmag_sersic_20130712.jpg)]] … … 25 25 26 26 === Radii === 27 If we compare the measured widths with the source sizes we see effects that are not understood. 27 28 28 29 29 ==== disks ==== … … 34 34 ==== bulges ==== 35 35 36 Here is a comparis ion of the measured width to the bulge effective radius.36 Here is a comparison of the measured width to the bulge effective radius. 37 37 38 38 [[Image(bulge_widths_20130712.jpg)]] … … 41 41 42 42 === Exponential magnitudes === 43 In general the magnitude fit with exponential model is slightly less than the expected value. However when the galaxy44 sample is restricted to pure disks the magnitude differences are clustered around zero.45 43 46 44 [[Image(dmag_exp_20130712.jpg)]] [[Image(dmag_exp_disks_20130712.jpg)]] … … 48 46 === Radii === 49 47 50 As with the sersice models, the measured width is about 2 x the modeled disk scale length.51 48 52 49 [[Image(disks_widths_exp_20130712.jpg)]] 53 50 54 51 == de Vacouleur Model == 55 The de Vacouleur model provides a good fit to elliptical galaxies. In our sample these are represented by the galaxies56 with ht == -6 pure disks57 58 {{{59 60 I(r) = I(0) exp[ -k * R ** (1 / 4) ]61 62 psphot extended source parameters measured for PS_MODE_DEV63 EXT_INST_MAG64 EXT_WIDTH_MAJ65 EXT_WIDTH_MIN66 EXT_THETA67 }}}68 69 It looks like there is something wrong with the DEV models.The magnitude differences are all over the place and there was a problem70 matching up the models with the pure bulge objects.71 52 72 53 [[Image(dmag_dev_20130712.jpg)]] [[Image(dmag_dev_bulges_20130712.jpg)]]
