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arXiv · 0711.4363

Blue Compact Dwarf Galaxies with Spitzer: The Infrared/Radio Properties

Yanling Wu·V. Charmandaris·J. R. Houck·J. Bernard-Salas·V. Lebouteiller·B. R. Brandl·D. Farrah
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Abstract

We study the correlation between the radio, mid-infrared and far-infrared properties for a sample of 28 blue compact dwarf (BCD) and low metallicity star-forming galaxies observed by Spitzer. We find that these sources extend the same far-infrared to radio correlation typical of star forming late type alaxies to lower luminosities. In BCDs, the 24um (or 22um) mid-infrared to radio correlation is similar to starburst galaxies, though there is somewhat larger dispersion in their q_24 parameter compared to their q_FIR. No strong correlations between the q parameter and galaxy metallicity or effective dust temperature have been detected, though there is a hint of decreasing q_24 at low metallicities. The two lowest metallicity dwarfs in our sample, IZw18 and SBS0335-052E, despite their similar chemical abundance, deviate from the average q$_{24}$ ratio in opposite manners, displaying an apparent radio excess and dust excess respectively.

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Yanling Wu, V. Charmandaris, J. R. Houck, J. Bernard-Salas, V. Lebouteiller, B. R. Brandl, D. Farrah. 2007-11-27. Blue Compact Dwarf Galaxies with Spitzer: The Infrared/Radio Properties. https://doi.org/10.1086/527288

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