Bibcode
Oteo, I.; Zhang, Z.-Y.; Yang, C.; Ivison, R. J.; Omont, A.; Bremer, M.; Bussmann, S.; Cooray, A.; Cox, P.; Dannerbauer, H.; Dunne, L.; Eales, S.; Furlanetto, C.; Gavazzi, R.; Gao, Y.; Greve, T. R.; Nayyeri, H.; Negrello, M.; Neri, R.; Riechers, D.; Tunnard, R.; Wagg, J.; Van der Werf, P.
Referencia bibliográfica
The Astrophysical Journal, Volume 850, Issue 2, article id. 170, 10 pp. (2017).
Fecha de publicación:
12
2017
Revista
Número de citas
42
Número de citas referidas
39
Descripción
We present ALMA J=3{--}2 and VLA J=1{--}0 observations of the dense
molecular gas tracers HCN, HCO+, and HNC in two lensed,
high-redshift starbursts selected from the Herschel-ATLAS survey:
H-ATLAS J090740.0‑004200 (SDP.9, {z}{spec}=1.575) and
H-ATLAS J091043.1‑000321 (SDP.11, {z}{spec}=1.786). In
SDP.9 we have detected all J=3{--}2 transitions and also HCN(1–0)
and HCO+(1–0). In SDP.11 we have detected
HCN(3–2) and HCO+(3–2). The amplification factors
for both galaxies have been determined from subarcsecond-resolution CO
and dust emission observations carried out with NOEMA and the SMA. The
HNC(1–0)/HCN(1–0) line ratio in SDP.9 suggests the presence
of photon-dominated regions, as happens in most local (U)LIRGs. The CO,
HCN, and HCO+ spectral line energy distribution (SLEDs) of
SDP.9 are compatible to those found for many local, IR-bright galaxies,
indicating that the molecular gas in local and high-redshift dusty
starbursts can have similar excitation conditions. We obtain that the
correlation between total IR ({L}{IR}) and dense line
({L}{dense}) luminosity in SDP.9 and SDP.11 and local
star-forming galaxies can be represented by a single relation. We argue
that the scatter of the {L}{IR}{--}{L}{dense}
correlation, together with the lack of sensitive dense molecular gas
tracer observations for a homogeneous sample of high-redshift galaxies,
prevents us from distinguishing differential trends with redshift. Our
results suggest that the intense star formation found in some
high-redshift, dusty, luminous starbursts is associated with more
massive dense molecular gas reservoirs and higher dense molecular gas
fractions.
Proyectos relacionados
Gas Molecular y Polvo en Galacias através del Tiempo Cósmico
Dos cuestiones fundamentales en la Astrofísica son la conversión de gas molecuar en estrellas y cómo este proceso físico depende del entorno en todas las escalas, desde sistemas planetarios, cúmulos estelares, galaxias hasta cúmulos de galaxias. El objectivo principal de este proyecto es el de estudiar la formación y evolución de galaxias a partir
Helmut
Dannerbauer