Alan Meert, Vinu Vikram, Mariangela Bernardi
We present simulations used to test the two dimensional decompositions of SDSS galaxies utilizing the fitting routine GALFIT and analysis pipeline PyMorph. Analysis showing the bias and scatter of the recovered parameters is presented for multiple combinations of simulated galaxy models and fit types. The simulations show that accurate measurement of single Sersic models is well constrained when using SDSS-quality data. Two component fits present a less robust image decomposition. Galaxies observed at higher redshift by Hubble are also simulated. We examine the bias created when fitting incorrect models to galaxies. Fitting a two-component Sersic + Exponential model to what is really just a single Sersic results in a noisier recovery of the input parameters, but these are not biased; fitting a single Sersic to what is truly a two-component system results in significant biases. These biases, for total magnitude and halflight radius in particular, should be useful in correcting other automatic fitting routines.
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http://arxiv.org/abs/1211.6123
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