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The SED of the nearby HI-massive LIRG HIZOA J0836-43: from the NIR to the radio domain

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 نشر من قبل Renee C. Kraan-Korteweg
 تاريخ النشر 2011
  مجال البحث فيزياء
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HIZOA J0836-43is one of the most HI-massive galaxies in the local (z<0.1) Universe. Not only are such galaxies extremely rare, but this coelacanth galaxy exhibits characteristics -- in particular its active, inside-out stellar disk-building -- that appear more typical of past (z ~ 1) star formation, when large gas fractions were more common. Unlike most local giant HI galaxies, it is actively star forming. Moreover, the strong infrared emission is not induced by a merger event or AGN, as is commonly found in other local LIRGs. The galaxy is suggestive of a scaled-up version of local spiral galaxies; its extended star formation activity likely being fueled by its large gas reservoir and, as such, can aid our understanding of star formation in systems expected to dominate at higher redshifts. The multi-wavelength imaging and spectroscopic observations that have led to these deductions will be presented. These include NIR (J H K) and MIR (Spitzer; 3-24micron) imaging and photometry, MIR spectroscopy, ATCA HI-interferometry and Mopra CO line emission observations. But no optical data, as the galaxy is heavily obscured due to its location in Vela behind the Milky Way.

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