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Title: ALMA [N ii] 205 μ m Imaging Spectroscopy of the Interacting Galaxy System BRI 1202-0725 at Redshift 4.7

Abstract

We present the results from Atacama Large Millimeter/submillimeter Array imaging in the [N ii] 205 μ m fine-structure line (hereafter [N ii]) and the underlying continuum of BRI 1202-0725, an interacting galaxy system at z = 4.7, consisting of a quasi-stellar object (QSO), a submillimeter galaxy (SMG), and two Ly α emitters, all within ∼25 kpc of the QSO. We detect the QSO and SMG in both [N ii] and continuum. At the ∼1″ (or 6.6 kpc) resolution, both the QSO and SMG are resolved in [N ii], with the de-convolved major axes of ∼9 and ∼14 kpc, respectively. In contrast, their continuum emissions are much more compact and unresolved even at an enhanced resolution of ∼0.″7. The ratio of the [N ii] flux to the existing CO(7−6) flux is used to constrain the dust temperature ( T {sub dust}) for a more accurate determination of the FIR luminosity L {sub FIR}. Our best estimated T {sub dust} equals 43 (±2) K for both galaxies (assuming an emissivity index β = 1.8). The resulting L {sub CO(7−6)}/ L {sub FIR} ratios are statistically consistent with that of local luminous infrared galaxies, confirming that L {sub CO(7−6)} traces the star formationmore » (SF) rate (SFR) in these galaxies. We estimate that the ongoing SF of the QSO (SMG) has an SFR of 5.1 (6.9) × 10{sup 3} M {sub ⊙} yr{sup −1} (±30%) assuming Chabrier initial mass function, takes place within a diameter (at half maximum) of 1.3 (1.5) kpc, and will consume the existing 5 (5) × 10{sup 11} M {sub ⊙} of molecular gas in 10 (7) × 10{sup 7} years.« less

Authors:
; ;  [1];  [2];  [3];  [4];  [5];  [6];  [7];  [8];  [9];  [10]
  1. National Astronomical Observatories, Chinese Academy of Sciences (CAS), Beijing 100012 (China)
  2. Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011 (China)
  3. Nucleo de Astronomia de la Facultad de Ingenieria, Universidad Diego Portales, Av. Ejercito Libertador 441, Santiago (Chile)
  4. Department of Physics, University of Crete, GR-71003 Heraklion (Greece)
  5. Purple Mountain Observatory, CAS, Nanjing 210008 (China)
  6. Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden (Netherlands)
  7. Departamento de Astronomía, Universidad de Concepción, Casilla 160-C, Concepción (Chile)
  8. Centre de Recherche Astrophysique de Lyon (CRAL), Observatoire de Lyon, CNRS, UMR5574, F-69230, Saint-Genis-Laval (France)
  9. Department of Physics, University of Oxford, Keble Road, Oxford OX1 3RH (United Kingdom)
  10. University of Hawaii, Institute for Astronomy, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States)
Publication Date:
OSTI Identifier:
22654453
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 842; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CARBON; CARBON MONOXIDE; DUSTS; EMISSION; EMISSIVITY; FINE STRUCTURE; GALAXIES; LUMINOSITY; MASS; MOLECULES; RED SHIFT; RESOLUTION; SPECTROSCOPY; STARS

Citation Formats

Lu, Nanyao, Xu, C. Kevin, Zhu, Lei, Zhao, Yinghe, Díaz-Santos, Tanio, Charmandaris, Vassilis, Gao, Yu, Van der Werf, Paul P., Privon, George C., Inami, Hanae, Rigopoulou, Dimitra, and Sanders, David B., E-mail: nanyao.lu@gmail.com. ALMA [N ii] 205 μ m Imaging Spectroscopy of the Interacting Galaxy System BRI 1202-0725 at Redshift 4.7. United States: N. p., 2017. Web. doi:10.3847/2041-8213/AA77FC.
Lu, Nanyao, Xu, C. Kevin, Zhu, Lei, Zhao, Yinghe, Díaz-Santos, Tanio, Charmandaris, Vassilis, Gao, Yu, Van der Werf, Paul P., Privon, George C., Inami, Hanae, Rigopoulou, Dimitra, & Sanders, David B., E-mail: nanyao.lu@gmail.com. ALMA [N ii] 205 μ m Imaging Spectroscopy of the Interacting Galaxy System BRI 1202-0725 at Redshift 4.7. United States. doi:10.3847/2041-8213/AA77FC.
Lu, Nanyao, Xu, C. Kevin, Zhu, Lei, Zhao, Yinghe, Díaz-Santos, Tanio, Charmandaris, Vassilis, Gao, Yu, Van der Werf, Paul P., Privon, George C., Inami, Hanae, Rigopoulou, Dimitra, and Sanders, David B., E-mail: nanyao.lu@gmail.com. Tue . "ALMA [N ii] 205 μ m Imaging Spectroscopy of the Interacting Galaxy System BRI 1202-0725 at Redshift 4.7". United States. doi:10.3847/2041-8213/AA77FC.
@article{osti_22654453,
title = {ALMA [N ii] 205 μ m Imaging Spectroscopy of the Interacting Galaxy System BRI 1202-0725 at Redshift 4.7},
author = {Lu, Nanyao and Xu, C. Kevin and Zhu, Lei and Zhao, Yinghe and Díaz-Santos, Tanio and Charmandaris, Vassilis and Gao, Yu and Van der Werf, Paul P. and Privon, George C. and Inami, Hanae and Rigopoulou, Dimitra and Sanders, David B., E-mail: nanyao.lu@gmail.com},
abstractNote = {We present the results from Atacama Large Millimeter/submillimeter Array imaging in the [N ii] 205 μ m fine-structure line (hereafter [N ii]) and the underlying continuum of BRI 1202-0725, an interacting galaxy system at z = 4.7, consisting of a quasi-stellar object (QSO), a submillimeter galaxy (SMG), and two Ly α emitters, all within ∼25 kpc of the QSO. We detect the QSO and SMG in both [N ii] and continuum. At the ∼1″ (or 6.6 kpc) resolution, both the QSO and SMG are resolved in [N ii], with the de-convolved major axes of ∼9 and ∼14 kpc, respectively. In contrast, their continuum emissions are much more compact and unresolved even at an enhanced resolution of ∼0.″7. The ratio of the [N ii] flux to the existing CO(7−6) flux is used to constrain the dust temperature ( T {sub dust}) for a more accurate determination of the FIR luminosity L {sub FIR}. Our best estimated T {sub dust} equals 43 (±2) K for both galaxies (assuming an emissivity index β = 1.8). The resulting L {sub CO(7−6)}/ L {sub FIR} ratios are statistically consistent with that of local luminous infrared galaxies, confirming that L {sub CO(7−6)} traces the star formation (SF) rate (SFR) in these galaxies. We estimate that the ongoing SF of the QSO (SMG) has an SFR of 5.1 (6.9) × 10{sup 3} M {sub ⊙} yr{sup −1} (±30%) assuming Chabrier initial mass function, takes place within a diameter (at half maximum) of 1.3 (1.5) kpc, and will consume the existing 5 (5) × 10{sup 11} M {sub ⊙} of molecular gas in 10 (7) × 10{sup 7} years.},
doi = {10.3847/2041-8213/AA77FC},
journal = {Astrophysical Journal Letters},
number = 2,
volume = 842,
place = {United States},
year = {Tue Jun 20 00:00:00 EDT 2017},
month = {Tue Jun 20 00:00:00 EDT 2017}
}