THE INTERSTELLAR MEDIUM AND FEEDBACK IN THE PROGENITORS OF THE COMPACT PASSIVE GALAXIES AT z ∼ 2

Quenched galaxies at z > 2 are nearly all very compact relative to z ~ 0, suggesting a physical connection between high stellar density and efficient, rapid cessation of star-formation. We present rest-frame UV spectra of Lyman-break galaxies (LBGs) at z ~ 3 selected to be candidate progenitors of the quenched galaxies at z ~ 2 based on their compact rest-frame-optical sizes and high [sigma[subSFR]]. We compare their UV properties to those of more extended LBGs of similar mass and star-formation rate. We propose that massive, compact galaxies undergo more rapid growth of their stellar mass content, perhaps because the gas accretion mechanisms are different, and quench sooner than normally sized LBGs at these epochs.