L[CLC]y[/CLC]α Emitters with Red Colors at [CLC][ITAL]z[/ITAL][/CLC] ≃ 2.4

We have carried out a search for Lyman alpha emission from galaxies at z~=2.4over a field of 1200 sq. arcmin using the CFH12K camera at the CFHT and acustom medium band filter. The search has uncovered 58 candidates,corresponding to a completeness-corrected source density of ~0.07 sq.arcmin^-2. Our sources have red colors (B-I~=1.8) which imply either that alarge fraction of the light is highly reddened and we are detecting Lyman alphathrough special lines of sight, or that these objects contain an underlyingolder stellar population. While for each individual object we cannotdiscriminate between these alternatives, we conclude that most of the objectsactually contain an older component because the star formation rates inferredfrom the picture based on reddening, applied to all candidates, would imply anexceedingly high star formation rate, i.e. more than two orders of magnitudeabove the peak cosmic star formation rate (e.g. Lilly et al. 1996).Comment: 9 pages plus 2 figures, ApJ Letters in pres