We investigate the stellar masses of the class of star-forming objects known as Luminous Compact Blue Galaxies ( LCBGs ) by studying a sample of galaxies in the distant cluster MS 0451.6-0305 at z \approx 0.54 with ground-based multicolor imaging and spectroscopy .
For a sample of 16 spectroscopically-confirmed cluster LCBGs ( colour B - V < 0.5 , surface brightness \mu _ { B } < 21 mag arcsec ^ { -2 } , and magnitude M _ { B } < -18.5 ) , we measure stellar masses by fitting spectral energy distribution ( SED ) models to multiband photometry , and compare with dynamical masses ( determined from velocity dispersion between 10 < \sigma _ { v } ~ { } ( km~ { } s ^ { -1 } ) < 80 ) , we previously obtained from their emission-line spectra .
We compare two different stellar population models that measure stellar mass in star-bursting galaxies , indicating correlations between the stellar age , extinction , and stellar mass derived from the two different SED models .
The stellar masses of cluster LCBGs are distributed similarly to those of field LCBGs , but the cluster LCBGs show lower dynamical-to-stellar mass ratios ( M _ { dyn } / M _ { \ast } = 2.6 ) than their field LCBG counterparts ( M _ { dyn } / M _ { \ast } = 4.8 ) , echoing trends noted previously in low-redshift dwarf elliptical galaxies .
Within this limited sample , the specific star formation rate declines steeply with increasing mass , suggesting that these cluster LCBGs have undergone vigorous star formation .