Stellar Mass and Stellar Mass-to-light Ratio–Color Relations for Low Surface Brightness Galaxies

Abstract

We estimate the stellar mass for a sample of low surface brightness galaxies (LSBGs) by fitting their multiband spectral energy distributions (SEDs) to the stellar population synthesis model. The derived stellar masses (log M * / M ⊙ ) span from 7.1 to 11.1, with a mean of log M * / M ⊙  = 8.5, which is lower than that for normal galaxies. The stellar mass-to-light ratio ( γ *) in each band varies little with the absolute magnitude but increases with higher M * . This trend of γ * with M * is even stronger in bluer bands. In addition, the γ * for our LSBGs slightly declines from the r band to the longer-wavelength bands. The log ( j  =  g , r , i , and z ) have relatively tight relations with optical colors of g  −  r and g  −  i . Compared with several representative γ *–color relations (MLCRs) from the literature, our MLCRs based on LSBG data are consistently among those literature MLCRs previously defined on diverse galaxy samples, and the existing minor differences between the MLCRs are caused by the differences in the SED model ingredients (including initial mass function, star formation history, and stellar population model), line fitting techniques, galaxy samples, and photometric zero-point, rather than the galaxy surface brightness itself, which distinguishes LSBGs from high surface brightness galaxies. Our LSBGs would be very likely to follow those representative MLCRs previously defined in diverse galaxy populations, if those main ingredients were taken into account.