Hawaii 167: A compact absorption-line object at z = 2.35

During the course of the Hawaii K-band (2.1 μm) survey (Songaila et al. 1994; Cowie et al. 1994) we have detected a compact object, Hawaii 167, lying at a redshift of 2.33, in which are seen both low- and high-ionization absorption lines. In the near-infrared we see broad Hα emission at a redshift of 2.35 but do not detect the other Balmer lines, [O II] λ3727, or [O III] λ5007. The absence of strong Mg II or C IV emission in the rest ultraviolet suggests that, at these wavelengths, we may be seeing a poststarburst galaxy rather than a quasar. Indeed, this class of object may be common enough to represent a major episode of galaxy formation, possibly the formation of the spheroids. However, Q0059-2735, the most extreme member of the class of Mg II absorbing broad absorption line quasars, is very similar to the present object, and there may be an evolutionary sequence or some other close connection between Hawaii 167 and the broad absorption line quasars.