Probing the metal enrichment of the intergalactic medium AT Z = 5 − 6 using the hubble space telescope

Zheng Cai, Xiaohui Fan, Romeel S Dave, Kristian Finlator, Ben Oppenheimer

Research output: Contribution to journalArticlepeer-review


We test the galactic outflow model by probing associated galaxies of four strong intergalactic CIV absorbers at z = 5–6 using the Hubble Space Telescope (HST) ACS ramp narrowband filters. The four strong CIV absorbers reside at z = 5.74, 5.52, 4.95, and 4.87, with column densities ranging from NCIV = 1013.8 cm2 to 1014.8 cm2. At z = 5.74, we detect an i-dropout Lyα emitter (LAE) candidate with a projected impact parameter of 42 physical kpc from the CIV absorber. This LAE candidate has a Lyα-based star formation rate (SFRLyα) of 2 Mo yr1 and a UV-based SFR of 4 Mo yr1. Although we cannot completely rule out that this i-dropout emitter may be an [OII] interloper, its measured properties are consistent with the CIV powering galaxy at z = 5.74. For CIV absorbers at z = 4.95 and z = 4.87, although we detect two LAE candidates with impact parameters of 160 kpc and 200 kpc, such distances are larger than that predicted from the simulations. Therefore we treat them as non-detections. For the system at z = 5.52, we do not detect LAE candidates, placing a 3-σ upper limit of SFRLyα ≈ 1.5 Mo yr1. In summary, in these four cases, we only detect one plausible CIV source at z = 5.74. Combining the modest SFR of the one detection and the three non-detections, our HST observations strongly support that smaller galaxies (SFRLyα . 2 Mo yr1) are main sources of intergalactic CIV absorbers, and such small galaxies play a major role in the metal enrichment of the intergalactic medium at z & 5.

Original languageEnglish (US)
JournalUnknown Journal
StatePublished - Sep 28 2017

ASJC Scopus subject areas

  • General

Fingerprint Dive into the research topics of 'Probing the metal enrichment of the intergalactic medium AT Z = 5 − 6 using the hubble space telescope'. Together they form a unique fingerprint.

Cite this