Detections of [O III] 88 μm in two quasars in the reionization epoch
Abstract
We report on detections with the Atacama Large Millimeter/sub-millimeter Array of the far-infrared [O III] 88 μm line and the underlying dust continuum in two quasars in the reionization epoch, J205406.48-000514.8 (hereafter J2054-0005) at z = 6.0391 ± 0.0002 and J231038.88+185519.7 (hereafter J2310+1855) at z = 6.0035 ± 0.0007. The [O III] luminosities of J2054-0005 and J2310+1855 are L[O III] = (6.8 ± 0.6) × 109 and (2.4 ± 0.6) × 109 L⊙, corresponding to ∼0.05% and 0.01% of the total infrared luminosity, LTIR, respectively. Combining these [O III] luminosities with [C II] 158 μm luminosities in the literature, we find that J2054-0005 and J2310+1855 have [O III]-to-[C II] luminosity ratios of 2.1 ± 0.4 and 0.3 ± 0.1, respectively, the latter of which is the lowest among objects so far reported at z > 6. Combining [O III] observations at z ≈ 6-9 from our study and the literature, we identify the [O III] line deficit: objects with a larger LTIR (total infrared luminosity) have lower L[O III]-to-LTIR ratios. Furthermore, we also find that the anti-correlation is shifted toward a higher LTIR value when compared with the local [O III] line deficit.
- Publication:
-
Publications of the Astronomical Society of Japan
- Pub Date:
- December 2019
- DOI:
- 10.1093/pasj/psz094
- arXiv:
- arXiv:1811.00030
- Bibcode:
- 2019PASJ...71..109H
- Keywords:
-
- galaxies: active;
- galaxies: high-redshift;
- galaxies: ISM;
- quasars: general;
- Astrophysics - Astrophysics of Galaxies;
- Astrophysics - High Energy Astrophysical Phenomena
- E-Print:
- 10 pages, 3 figures, 1 table, accepted for publication in PASJ