Abstract
L988 is a large (~05 ? 07) dark cloud complex at about 600 pc that contains several bright pre-main-sequence objects (such as V1331 Cyg and LkH? 321), but this paper deals in detail only with a small region on its eastern edge, near the HAeBe star LkH? 324. That star and its distant companion LkH? 324SE lie at the apex of a V-shaped area apparently excavated from the edge of L988, and are the brightest members of a small cluster containing about 50 H?-emission stars. A median age of about 0.6 Myr (with large dispersion) is inferred from its color-magnitude diagram, constructed from VRI photometry to V = 22. Keck HIRES spectra show that LkH? 324SE is probably also an HAeBe. Its image is nonstellar, and within 3'' to the northwest are three condensations having complex [S II] and [O I] profiles and radial velocities up to -200 km s-1. They probably originate in an outflow from LkH? 324SE. A bright Ap star with strong Si II lines is embedded in the heavy obscuration 8' to the west. It illuminates a small reflection nebulosity, has several faint H? emitters nearby, and shares the radial velocity of L988, so clearly it was formed in that cloud. It demonstrates again that such chemical peculiarities can be established very early in young stars of moderate mass.
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