An imaging and spectroscopic study of the z(abs)=3.38639 damped Ly alpha system in Q0201+1120: Clues to star formation at high redshift

We present the results of a series of imaging and spectroscopic observation s aimed at identifying and studying the galaxy responsible for the z(abs) = 3.38639 damped Ly alpha system in the quasar z(em) = 3.61 quasar Q0201 + 1 120. We find that the damped Ly alpha systems (DLA) is part of a concentrat ion of matter that includes at least four galaxies (probably many more) ove r linear comoving dimensions greater than 5 h(-1) Mpc. The absorber may be a 0.7L* galaxy at an impact parameter of 15 h(-1) kpc, but follow-up spectr oscopy is still required for positive identification. The gas is turbulent, with many absorption components distributed over similar to 270 km s(-1) a nd a large spin temperature, T-s greater than or similar to 4000 K. The met allicity is relatively high for this redshift, Z(DLA) similar or equal to 1 /20 Z.. From consideration of the relative ratios of elements that have dif ferent nucleosynthetic timescales, it would appear that the last major epis ode of star formation in this DLA occurred at z greater than or similar to 4.3, more than similar to 500 Myr prior to the time when we observe it.