Dust temperature and the submillimetre-radio flux density ratio as a redshift indicator for distant galaxies

Jun, 1999
6 pages
Published in:
  • Mon.Not.Roy.Astron.Soc. 309 (1999) 955-960
e-Print:

Citations per year

19992005201120172023024681012
Abstract: (arXiv)
It is difficult to identify the distant galaxies selected in existing submillimetre-wave surveys, because their positions are known at best to only several arcseconds. Centimetre-wave VLA observations are required in order to determine positions to subarcsecond accuracy, and so to allow reliable optical identifications to be made. Carilli & Yun pointed out that the ratio of the radio to submillimetre-wave flux densities provides a redshift indicator for dusty star-forming galaxies, when compared with the tight correlation between the far-infrared and radio flux densities observed in low-redshift galaxies. This method does provide a useful, albeit imprecise, indication of the distance to a submillimetre-selected galaxy. Unfortunately, it does not provide an unequivocal redshift estimate, as the degeneracy between the effects of increasing the redshift of a galaxy and decreasing its dust temperature is not broken.