In order to properly fit the panchromatic SEDs of KINGFISH spirals using Popescu et al. (2011) model, accurate values for the photometric parameters of each galaxy are needed at all available wavelengths, such as disk inclination, disk scale-length, bulge-to-disk ratio (B/D) or bulge Sérsic index. To obtain these parameters I have used GALFIT data analysis algorithm to fit so far the images of the unbarred spirals from the KINGFISH sample, by doing bulge-disk decomposition. As accurate sky values are essential in deriving accurate values for the flux densities/integrated magnitudes at each wavelength but also for the disk size / disk scale-length, I am checking the output results obtained with GALFIT (for sky and disk axis-ratio values) and the flux densities for each wavelength (tabulated in the literature) by doing surface photometry for these images using the curve-of-growth (CoG) method, using routines built by me (in IDL). Preliminary results on this were presented recently in a poster, at the IAU XIX GA, Honolulu, Focus Meeting 7.
This study is important as accurate SED modelling is essential when extracting parameters like dust mass, dust temperature, star-formation rate (SFR) in order to understand the dust heating processes and dust composition and quantity, the fraction of radiation absorbed and reemitted by dust and where this radiation is coming from (in what fraction is it coming from old/young stars), in deriving the luminosities of the young and old stellar populations, in deriving scalling relations. An accurate modelling of the panchromatic SED taking into account the corrections for dust effects (from Pastrav et al. 2013a,2013b) could potentially reduce the scatter in the main scalling relations of spiral galaxies, which will be important for models of galaxy formation and evolution.
Once the analysis of this small sample is completed, the plans are to analyse a much larger sample of spiral galaxies - the ones from GAMA (Galaxy and Mass Assembly) survey.