INVESTIGADORES
ORTEGA Martin Eduardo
artículos
Título:
Outflow activity in the UCHII region G045.47+0.05
Autor/es:
M. E. ORTEGA; S. PARON; S. CICHOWOLSKI; M. RUBIO; G. DUBNER
Revista:
ASTRONOMY AND ASTROPHYSICS
Editorial:
EDP SCIENCES S A
Referencias:
Lugar: Paris; Año: 2012 vol. 546 p. 96 - 107
ISSN:
0004-6361
Resumen:
Aims: This work aims at investigating the molecular gas in the
surroundings of the ultra-compact HII region G045.47+0.05 looking for
evidence of molecular outflows. Methods: We carried out
observations towards a region of 2' × 2' centered at RA =
19h14m25.6s, Dec =
+11°09'27.6''(J2000) using the Atacama Submillimeter Telescope
Experiment (ASTE; Chile) in the 12CO J = 3-2, 13CO
J = 3-2, HCO+J = 4-3, and CS J = 7-6 lines with an angular
resolution of 22''. We complement these observations with public
infrared data. Results: We characterize the physical parameters
of the molecular clump where G045.47+0.0 is embedded. The detection of
the CS J = 7-6 line emission in the region reveals that the
ultra-compact HII region G045.47+0.0 has not completely disrupted the
dense gas where it was born. The HCO+ abundance observed
towards G045.47+0.0 suggests there is molecular outflow activity in the
region. From the analysis of the 12CO J = 3-2 transition we
report bipolar molecular outflows with a total mass of about 300
Msun. We derive a dynamical time (flow's age) of about
105 yr for the outflow gas, in agreement with the presence of
an ultra-compact HII region. We identify the source 2MASS
19142564+1109283 as the massive protostar candidate to drive the
molecular outflows. Based on the analysis of its spectral energy
distribution, we infer that it is an early B-type star of about 15
Msun. The results of this work support the scenario where
the formation of massive stars, at least up to early B-type stars, is
similar to that of low-mass stars.