A study of the Galactic star forming region IRAS 02593+6016/S 201 in infrared and radio wavelengths *,**
Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400 005, India
2 National Astronomical Observatory of Japan, Osawa 2-21-1, Mitaka, Tokyo 181-8588, Japan
3 National Centre for Radio Astrophysics, Post Bag 3, Ganeshkhind, Pune 411 007, India
4 Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, 50125 Firenze, Italy
Corresponding author: D. K. Ojha, firstname.lastname@example.org
Accepted: 3 November 2003
We present infrared and radio continuum observations of the S 201 star forming region. A massive star cluster is seen, which contains different classes of young stellar objects. The near-infrared colour-colour and colour-magnitude diagrams are studied to determine the nature of these sources. We have discovered knots of molecular hydrogen emission at 2.122 μm in the central region of S 201. These knots are clearly seen along the diffuse emission to the north–west and are probably obscured Herbig-Haro objects. High sensitivity and high resolution radio continuum images from GMRT observations at 610 and 1280 MHz show an arc-shaped structure due to the interaction between the HII region and the adjacent molecular cloud. The ionization front at the interface between the HII region and the molecular cloud is clearly seen comparing the radio, molecular hydrogen and Brγ images. The emission from the carriers of Unidentified Infrared Bands in the mid-infrared 6–9 μm (possibly due to PAHs) as extracted from the Midcourse Space Experiment survey (at 8, 12, 14 and 21 μm) is compared with the radio emission. The HIRES processed IRAS maps at 12, 25, 60 and 100 μm have also been used for comparison. The spatial distribution of the temperature and the optical depth of the warm dust component around the S 201 region has been generated from the mid-infrared images.
Key words: Herbig-Haro objects / stars: formation / ISM: individual objects: S 201
This paper is based on observations made with the Italian Telescopio Nazionale Galileo (TNG) operated on the island of La Palma by the Centro Galileo Galilei of the CNAA (Consorzio Nazionale per l'Astronomia e l'Astrofisica) at the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias.
This publication makes use of data products from the Two Micron All Sky Survey, which is a joint project of the University of Massachusetts and the Infrared Processing and Analysis Center/California Institute of Technology, funded by the National Aeronautics and Space Administration and the National Science Foundation. IPAC is thanked for providing HIRES processed IRAS data.
© ESO, 2004