artículo
ALMA [N II] 205 mu m Imaging Spectroscopy of the Interacting Galaxy System BRI 1202-0725 at Redshift 4.7
Fecha
2017Registro en:
10.3847/2041-8213/aa77fc
2041-8213
2041-8205
WOS:000403940100001
Autor
Lu, Nanyao
Zhao, Yinghe
Diaz Santos, Tanio
Kevin Xu, C.
Charmandaris, Vassilis
Gao, Yu
van der Werf, Paul P.
Privon, George C.
Inami, Hanae
Rigopoulou, Dimitra
Sanders, David B.
Zhu, Lei
Institución
Resumen
We present the results from Atacama Large Millimeter/submillimeter Array imaging in the [N II] 205 mu 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 alpha emitters, all within similar to 25 kpc of the QSO. We detect the QSO and SMG in both [N II] and continuum. At the similar to 1 '' (or 6.6 kpc) resolution, both the QSO and SMG are resolved in [N II], with the de-convolved major axes of similar to 9 and similar to 14 kpc, respectively. In contrast, their continuum emissions are much more compact and unresolved even at an enhanced resolution of similar to 0 ''.7. The ratio of the [N II] flux to the existing CO(7-6) flux is used to constrain the dust temperature (T-dust) for a more accurate determination of the FIR luminosity L-FIR. Our best estimated T-dust equals 43 (+/- 2) K for both galaxies (assuming an emissivity index beta = 1.8). The resulting LCO(7-6)/LFIR ratios are statistically consistent with that of local luminous infrared galaxies, confirming that LCO(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) x 10(3) M-circle dot yr(-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) x 10(11) M-circle dot of molecular gas in 10 (7) x 10(7) years.
Ítems relacionados
Mostrando ítems relacionados por Título, autor o materia.