High spatial resolution continuum and Hɑ imaging of the high-redshift IRAS source FSC 10214+4724

Abstract

High spatial resolution images have been obtained of the high-redshift (z = 2.286) IRAS source FSC 10214+4724 at wavelengths corresponding to the optical continuum and Hɑ in the object's rest frame. The continuum shows two clumps separated by ~1" (~10 kpc) and aligned approximately north-south. The structure appears similar at rest wavelengths of 0.38, 0.64, and 0.67 μm. The continuum morphology suggests two separate concentrations of luminosity, likely the nuclei of interacting galaxies, although a large galaxy bifurcated by an immense dust lane cannot be ruled out. The southern component is predominantly extended in the east-west direction on a scale of -0."5 (5 kpc), consistent with the position and elongation of the radio source reported in 1992 by Lawrence et al. The Hɑ emission is centered on the southern component of the galaxy and is unresolved with a diameter smaller than 0."4 ( < 3.5 kpc). A simple explanation for the current observations is an interacting system comprised of two or more highly luminous (~10^(12) L_☉) galaxies, one of which contains a dust enshrouded quasar that generates the bulk of the bolometric luminosity (~ 5 x 10^(14) L_☉) of the system.