Physical Sciences and Mathematics Commons^™

The Scatter In The Relationship Between Redshift And The Radio-To-Submm Spectral Index, C L. Carilli, Min S. Yun

Min S. Yun

We derive the scatter in the relationship between redshift and the radio-to-submillimeter spectral index, a135.40, using the observed spectral energy distributions of 17 low-redshift star-forming galaxies. A mean galaxy model is derived, along with the rms scatter in a13.540. The scatter is roughly constant with redshift. Constant rms scatter, combined with the Ñattening of the mean a13.540-z relationship with increasing redshift, leads to increasing uncertainty for redshift estimates at high redshifts. Normalizing by the dust temperature in the manner proposed by Blain decreases the scatter in a13.540 for most of the sample, but does not remove outliers, and free-free absorption …