Starburst Galaxies. III. Properties of a Radio-selected Sample*

摘要: We have analyzed the properties of 20 most radio-luminous UGC starburst galaxies from Condon, Frayer, & Broderick. Near-infrared images, spectra, and optical rotation curves were presented in Smith et al. In this paper, we use these data published radio to assess stellar populations, dust contents, ionizing conditions, dynamics starbursts. Certain star formation occurring differ those observed locally. The infrared excesses (IREs) are lower than span a narrower range values Galactic H II regions. starbursts appear produce higher proportion photons Consequently, initial mass functions (IMFs) may be more strongly biased toward high-mass formation. also contain fewer old regions Milky Way. Furthermore, IRE is likely influenced by presence large reservoirs gas that absorb larger fraction Lyman continuum photons. OB far-infrared luminosities imply upper IMF (M > 10 M?) characterized slope 2.7 ? 0.2. thus bears strong similarity Magellanic associations. Optical line ratios indicate excitation conditions present. conclude near-infrared light many dominated heavily obscured mixture emission evolved red stars young blue with small contributions (? 5%) thermal hot dust, under assumptions or SMC extinction law can applied systems true reddening curve follows one models currently existing literature. some cases, amounts required explain colors. amount exceeds predicted comparisons colors low-luminosity active galactic nucleus (AGN). Emission if present, dilutes CO index. activity redder, luminous peaked. hosting exhibit wide morphological star-forming properties. While all host interacting systems, nuclear separations nuclei 1 Mpc. dynamical behavior ranges relaxed perturbed. off-nuclear sites conditions. Spatially extended LINER consistent shock produced superwinds galaxy-galaxy collisions. Violent occurs over physical scale Systems containing mergers widely separated possess similar luminosities. burst regulated internal structures not galaxies.