| Title | Molecular gas in z similar to 6 quasar host galaxies |
| Authors | Decarli, Roberto Pensabene, Antonio Venemans, Bram Walter, Fabian Banados, Eduardo Bertoldi, Frank Carilli, Chris L. Cox, Pierre Fan, Xiaohui Farina, Emanuele Paolo Ferkinhoff, Carl Groves, Brent A. Li, Jianan Mazzucchelli, Chiara Neri, Roberto Riechers, Dominik A. Uzgil, Bade Wang, Feige Wang, Ran Weiss, Axel Winters, Jan Martin Yang, Jinyi |
| Affiliation | INAF Osservatorio Astrofis & Sci Spazio Bologna, Via Gobetti 93-3, I-40129 Bologna, Italy Univ Bologna, Alma Mater Studiorum, Dipartimento Fis & Astron, Via Gobetti 93-2, I-40129 Bologna, Italy Univ Milano Bicocca, Dipartimento Fis G Occhialini, Piazza Sci 3, I-20126 Milan, Italy Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany Leiden Univ, Leiden Observ, POB 9513, NL-2300 RA Leiden, Netherlands Pete V Domen Array Sci Ctr, Natl Radio Astron Observ, POB 0, Socorro, NM 87801 USA Univ Bonn, Argelander Inst Astron, Hugel 71, D-53121 Bonn, Germany UPMC Univ Paris 6, Sorbonne Univ, Paris, France CNRS, UMR 7095, Paris, France Inst Astrophys Paris, 98b Blvd Arago, F-75014 Paris, France Univ Arizona, Steward Observ, 933 N Cherry St, Tucson, AZ 85721 USA NSFs NOIRLab, Gemini Observ, 670 N Aohoku Pl, Hilo, HI 96720 USA Winona State Univ, Dept Phys, Winona, MN 55987 USA Univ Western Australia, ICRAR M468, 35 Stirling Hwy, Crawley, WA 6009, Australia Australian Natl Univ, Res Sch Astron & Astrophys RSAA, Weston, ACT 2611, Australia Peking Univ, Sch Phys, Dept Astron, 5 Yiheyuan Rd, Beijing 10087, Peoples R China Peking Univ, Kavli Inst Astron & Astrophys, 5 Yiheyuan Rd, Beijing 100871, Peoples R China Tsinghua Univ, Dept Astron, Beijing 100084, Peoples R China European Southern Observ, Alonso de Cordova 3107, Vitacura, Region Metropol, Chile Inst Radioastron Millimetr IRAM, 300 Rue Piscine, F-38400 St Martin Dheres, France Cornell Univ, Dept Astron, Space Sci Bldg, Ithaca, NY 14853 USA CALTECH, Dept Astron, MC249-17, Pasadena, CA 91125 USA Max Planck Inst Radioastron, Hugel 69, D-53121 Bonn, Germany |
| Keywords | STAR-FORMING GALAXIES INFRARED LINE EMISSION C II EMISSION ATOMIC CARBON INTERSTELLAR-MEDIUM DUST EMISSION THERMAL EMISSION BLACK-HOLE WARM DUST REDSHIFT |
| Issue Date | 16-Jun-2022 |
| Publisher | ASTRONOMY & ASTROPHYSICS |
| Abstract | We investigate the molecular gas content of z similar to 6 quasar host galaxies using the Institut de Radioastronomie Millimetrique Northern Extended Millimeter Array. We targeted the 3mm dust continuum, and the line emission from CO(6-5), CO(7-6), and [C I](2-1) in ten infrared-luminous quasars that have been previously studied in their 1mm dust continuum and [C II] line emission. We detected CO(7-6) at various degrees of significance in all the targeted sources, thus doubling the number of such detections in z similar to 6 quasars. The 3mm to 1mm flux density ratios are consistent with a modified black body spectrum with a dust temperature T-dust similar to 47K and an optical depth tau(nu) = 0 :2 at the [C II] frequency. Our study provides us with four independent ways to estimate the molecular gas mass, M-H2, in the targeted quasars. This allows us to set constraints on various parameters used in the derivation of molecular gas mass estimates, such as the mass per luminosity ratios alpha(CO) and alpha([CII]), the gas-to-dust mass ratio delta(g/d), and the carbon abundance [C]/H-2. Leveraging either on the dust, CO, [C i], or [C II] emission yields mass estimates of the entire sample in the range M-H2 similar to 10(10)-10(11) M-circle dot. We compared the observed luminosities of dust, [C II], [C I], and CO(7-6) with predictions from photo-dissociation and X-ray dominated regions. We find that the former provide better model fits to our data, assuming that the bulk of the emission arises from dense (nH > 10(4) cm(-3)) clouds with a column density N-H similar to 10(23) cm(-2), exposed to a radiation field with an intensity of G(0) similar to 10(3) (in Habing units). Our analysis reiterates the presence of massive reservoirs of molecular gas fueling star formation and nuclear accretion in z similar to 6 quasar host galaxies. It also highlights the power of combined 3mm and 1mm observations for quantitative studies of the dense gas content in massive galaxies at cosmic dawn. |
| URI | http://hdl.handle.net/20.500.11897/648023 |
| ISSN | 0004-6361 |
| DOI | 10.1051/0004-6361/202142871 |
| Indexed | SCI(E) |
| Appears in Collections: | 物理学院 科维理天文与天体物理研究所 |
