Grupo de Sistemas Estelares

Persi, P., Marenzi, A. R., Olofsson, G., Kaas, A. A., Nordh, L., Huldtgren, M., Abergel, A., André, P., Bontemps, S., Boulanger, F., Burggdorf, M., Casali, M. M., Cesarsky, C. J., Copet, E., Davies, J., Falgarone, E., Montmerle, T., Perault, M., Prusti, T., Puget, J. L., and Sibille, F.
Astronomy and Astrophysics, v.357, p.219-224 (2000)
05/2000

ABSTRACT

We present the results of an ISOCAM survey of the Chamaeleon I dark cloud conducted in two broad-band filters at 6.7 and 14.3 mu m. In an area of 0.59 sq.deg. we have detected a total of 282 mid-IR sources with 103 sources observed in both filters. Combining the ISOCAM observations with the I, J, and K_s data obtained with DENIS, we have found 108 pre-main-sequence (PMS) stars in the region, of which 34 were previously unidentified. Several of these newly discovered young stellar objects are relatively faint suggesting a population in Cha I of very low mass objects that probably includes brown dwarfs in their early contraction phases. Finally, most of the PMS stars show the spectral index computed between 2.2 and 14.3 mu m typical of Class II sources. The luminosity function (LF) derived for our detected PMS stars is discussed. ISO is an ESA project with instruments funded by ESA Member States (especially the PI countries: France, Germany, the Netherlands and the United Kingdom) and with the participation of ISAS and NASA. Tables 1 and 2 are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/Abstract.html Tables 3 and 4 are only available with the on-line publication at http://link.springer.de/link/service/journals/00230/