GCN Circular 4271
J.X. Prochaska (UCO/Lick) on behalf of GRAASP reports: "We have further analyzed the Keck/HIRES spectrum of GRB 051111. A total integration of 5400s was acquired covering 4200-8400Ang with a SNR~20 per 1.3km/s pixel at 5500Ang. The main component is ~30km/s wide, contains 90% of the gas and is centered at z=1.54948 +/- 0.00001. The full line-profile, however, spans ~250km/s. The gas in the GRB host is remarkable for several reasons: (1) The SiII 1808 and ZnII 2026, 2062 transitions are saturated implying log N(Zn) > 13.5 and log N(Si) > 15.9. We believe these are the largest Zn and Si column densities recorded outside the Local Group; (2) The observed Zn/Fe ratio is [Zn/Fe] > 1.2 indicating significant differential depletion; (3) We detect the fine-structure SiII* 1816 transition and observe that the weak MgI 2026 transition is saturated. (4) Perhaps more stunning, we detect nearly every FeII excited transition in the Morton catalog redward of 2300Ang. This includes several transitions from the 977K excited level. These suggest both a large volume density and a warm gas. We place a lower limit to N(HI) assuming a solar metallicity for the gas: log N(HI) > 20.8. The high metal column density and significant differential depletion imply a rest-frame V-band extinction A(V) > 0.5mag. Adopting the Milky Way extinction curve, this implies an observed R-band extinction A(R_obs) > 1.4mag. The extinction is several times larger if one adopts the SMC or Calzetti curves. We also identify a very strong intervening MgII system at z=1.18975. These data were kindly obtained by the Keck observing staff during engineering and will be publically released. For now, the raw data are archived at www.graasp.org." This GCN may be cited.