L-band (3.5 m) IR-excess in massive star formation
I. 30 Doradus
Stockholm Observatory, AlbaNova University Center, 106 91 Stockholm, Sweden e-mail: firstname.lastname@example.org
2 School of Physics, University of New South Wales, Sydney, NSW 2052, Australia e-mail: email@example.com
Accepted: 18 April 2005
L-band data of 30 Doradus at 3.5 μm taken with SPIREX (South Pole Infrared Explorer) is presented. The photometry was combined with 2MASS JHK data at 1.25-2.2 μm. Colour-colour and colour-magnitude diagrams are constructed and used to determine the sources with infrared excess. These are interpreted as circumstellar disks, and enable the fraction of sources with disks (the cluster disk fraction or CDF) to be determined. We find that ~42% of the sources detected at L-band in 30 Doradus have an IR-excess.
Key words: stars: circumstellar matter / stars: formation / stars: evolution / Hertzsprung-Russell (HR) and C-M diagrams / planetary systems: protoplanetary disks / stars: pre-main sequence
© ESO, 2005