Deep HST/PC Images of a Young Radio Galaxy at z=2.390

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We present deep 63-orbit HST/PC images at 0.06" FWHM resolution in the filters B₄50, V₆06 & I₈14 - as well as in redshifted Lya - of the radio source LBDS 53W002, a compact narrow-line galaxy at z=2.390. These images allow us to distinguish several morphological components: (1) an unresolved nuclear point source (<=500 pc at z=2.390 for Ho=75, qo=0), likely the central AGN which contains <=20-25% of the total light in BVI; (2) a compact continuum core (re 0.05"); (3) a more extended envelope with an r¹/4-like light-profile and re 0.25" (2 kpc); (4) two blue ''clouds'' roughly colinear across the nucleus aligned with the radio source axis and contained well within the size of the radio source. (B-I) color maps may suggest a narrow dust lane crossing between the nucleus and the smaller blue cloud. The radio source is not smaller than the distance between the blue continuum clouds, and coincides with a bright Lya ''arc'' in the western cloud, suggesting that jet-induced star-formation could cause both blue clouds, except the outer parts of the western cloud. The shape of this larger blue cloud suggests reflected AGN continuum-light shining through a cone (plus re-radiated Lya in emission). The OVRO interferometric CO-detection (Scoville et al. 1997) on both sides of 53W002 - and in the same direction as the continuum clouds and the radio jet - also suggest a star-bursting region induced by its radio jet, at least in the inner parts. Even at radio powers 1.5 dex fainter than the 3CR sources, we thus find many of the same aligned features and complex morphology, although at much smaller angular scales and lower optical-UV luminosities. We discuss the consequences for 53W002's formation in the context of the 16 sub-galactic objects at z 2.40 around 53W002 (Pascarelle et al. 1996).