Abstract
A&A 646, A138 (2021) We compare the relations among various integrated characteristics of ~25,000
low-redshift (z<1.0) compact star-forming galaxies (CSFGs) from Data Release 16
(DR16) of the Sloan Digital Sky Survey (SDSS) and of high-redshift (z>1.5)
star-forming galaxies (SFGs) with respect to oxygen abundances, stellar masses
M*, far-UV absolute magnitudes M(FUV), star-formation rates SFR and specific
star-formation rates sSFR, Lyman-continuum photon production efficiencies
(xi_ion), UV continuum slopes \beta, [OIII]5007/[OII]3727 and
[NeIII]3868/[OII]3727 ratios, and emission-line equivalent widths
EW([OII]3727), EW([OIII]5007), and EW(H\alpha). We find that the relations for
low-z CSFGs with high equivalent widths of the H\beta emission line,
EW(H\beta)>100A, and high-z SFGs are very similar, implying close physical
properties in these two categories of galaxies. Thus, CSFGs are likely
excellent proxies for the SFGs in the high-z Universe. They also extend to
galaxies with lower stellar masses, down to ~10^6 Msun, and to absolute FUV
magnitudes as faint as -14 mag. Thanks to their proximity, CSFGs can be studied
in much greater detail than distant SFGs. Therefore, the relations between the
integrated characteristics of the large sample of CSFGs studied here can prove
very useful for our understanding of high-z dwarf galaxies in future
observations with large ground-based and space telescopes.