Details

Autor(en) / Beteiligte

• Díaz, C. Gonzalo
• Ryan-Weber, Emma V
• Cooke, Jeff
• Koyama, Yusei
• Ouchi, Masami

Titel

Large-scale environment of z ∼ 5.7 C iv absorption systems –II. Spectroscopy of Lyman α emitters

Ist Teil von

• Monthly notices of the Royal Astronomical Society, 2015-04, Vol.448 (2), p.1240-1270

Ort / Verlag

Oxford University Press

Erscheinungsjahr

2015

Link zum Volltext

Quelle

Free E-Journal (出版社公開部分のみ）

Beschreibungen/Notizen

• The flow of baryons to and from a galaxy, which is fundamental for galaxy formation and evolution, can be studied with galaxy-metal absorption system pairs. Our search for galaxies around C iv absorption systems at z ∼ 5.7 showed an excess of photometric Lyman α emitter (LAE) candidates in the fields J1030+0524 and J1137+3549. Here, we present spectroscopic follow-up of 33 LAEs in both fields. In the first field, three out of the five LAEs within 10h −1 projected comoving Mpc from the C iv system are within ±500 km s−1 from the absorption at $z_{{\rm C\,{\small iv}}}=5.7242\pm 0.0001$ . The closest candidate (LAE 103027+052419) is robustly confirmed at $212.8^{+14}_{-0.4}\;h^{-1}$ physical kpc from the C iv system. In the second field, the LAE sample is selected at a lower redshift (Δz ∼ 0.04) than the C iv absorption system as a result of the filter transmission and, thus, do not trace its environment. The observed properties of LAE 103027+052419 indicate that it is near the high-mass end of the LAE distribution, probably having a large H i column density and large-scale outflows. Therefore, our results suggest that the C iv system is likely produced by a star-forming galaxy which has been injecting metals into the intergalactic medium since z > 6. Thus, the C iv system is either produced by LAE 103027+052419, implying that outflows can enrich larger volumes at z > 6 than at z ∼ 3.5, or an undetected dwarf galaxy. In either case, C iv systems like this one trace the ionized intergalactic medium at the end of cosmic hydrogen reionization and may trace the sources of the ionizing flux density.