Near and Mid-infrared images of the massive star forming complex G9.62+0.19^*

¹ Istituto Astrofisica Spaziale e Fisica Cosmica, CNR, Via del Fosso del Cavaliere, 00133, Roma, Italy e-mail: persi@rm.iasf.cnr.it
² Instituto de Astronomía, UNAM, Apartado Postal 877, Ensenada, Baja California, CP 22833, Mexico
³ Harvard-Smithsonian Center for Astrophysics, 60 Garden St, Cambridge, MA 02138, USA
⁴ Las Campanas Observatory, Carnegie Institution of Washington, Casilla 601, La Serena, Chile
⁵ Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, 50125 Firenze, Italy
⁶ European Southern Observatory, Alonso de Cordoba 3107, Santiago, Chile

Corresponding author: P. Persi, persi@rm.iasf.cnr.it

Received: 26 April 2002
Accepted: 8 October 2002

Abstract

A near- and mid-infrared study of the star formation complex G9.62+0.19 is presented. It includes photometrically calibrated images through wide-band JHK and narrow-band Brγ, H₂ and 12.5 filters. These were taken at Las Campanas, La Silla and OAN-San Pedro Mártir. We found evidence of two embedded young clusters of O-B5 stars associated with the radio components B and C, one compact and one ultracompact HII region. The data suggest the presence of a third, more dispersed cluster of more luminous infrared stars at the southern edge of the cloud complex. A large fraction of the star members of each cluster exhibit significant infrared excess. We confirm the detection of a very red near- and mid-infrared source immersed in the molecular hot core (component F). An H₂ shocked gas knot, probably an obscured Herbig-Haro object, was found associated to the blue-shifted lobe of the high-velocity molecular outflow in this core. The properties of the individual sources are discussed in detail.