The Galaxy And Mass Assembly (GAMA) survey has to date obtained spectra, redshifts, and 21-band multi-facility photometry for over 200,000 galaxies in five survey regions that total nearly 300 square degrees on sky. We consider here a low-redshift (z<0.06), volume-limited subsample of ~8,000 GAMA galaxies that have been morphologically classified by the survey team. In order to quantify the separate bulge and disk properties of these galaxies, we apply a large-scale automated procedure for fitting images with 2D, multi-component structure models, including evaluation of fit convergence using a grid of input parameter values for each galaxy. From this analysis, we calculate the total bulge and disk contributions to the local galaxy stellar mass budget and derive mass-size relations for both pure spheroid/disk systems and the separate bulge/disk components of multi-component galaxies. We further examine the fraction of total stellar mass assembled in spheroid and disk structures as a function of galaxy environment, where environment is quantified on multiple scales from membership in large-scale filaments to groups/clusters and down to local pairings. We then discuss the effect of environmental conditions on the mechanisms of stellar mass assembly, including the implied balance between merger accumulation and in situ mass growth in different environment regimes.
|Publication status||Published - Jan 2016|