We present the results of deep (Ks=18.9) sub-arcsec resolution (0.3 arcsec) imaging observations of the Cederblad 110 region in the Chamaeleon I dark cloud. This region (roughly 5arcminx5 arcmin ) is characterized by the presence of six ISOCAM-detected young stellar objects (YSOs). Our images have recovered all these sources at near-infrared (near-IR) wavelengths. Ced 110 IRS4, the brightest object in the region, is associated with a remarkable near-IR bipolar nebulosity. Ced 110 IRS6 is resolved in a double system IRS6a and IRS6b with a separation of ~ 2arcsec (~ 320 AU at the distance of the Cha I cloud). We have combined 1.3 mm, far and mid-IR fluxes from the literature with our JHK data and obtained the spectral energy distributions (SEDs) for three (IRS4, IRS6a and ISO-ChaI86) of the six ISOCAM sources in the region. We modelled the SEDs of IRS6a and ISO-ChaI86 with a spherically symmetric dusty envelope, using the DUSTY code. These objects are clear Class I sources of the cloud. Finally, we report the detection of three new objects in this region (NIR 72, 84 and 89) with significant near-IR excess. If these sources are associated with the cloud, the derived luminosities and masses suggest that they are candidate young brown dwarfs of Chamaeleon I. Based on observations collected at the European Southern Observatory, Chile, ESO proposal N.65.I-0054.
Sub-arces resolution near-infrared images of the Cederblad 110 region
2001
Abstract
We present the results of deep (Ks=18.9) sub-arcsec resolution (0.3 arcsec) imaging observations of the Cederblad 110 region in the Chamaeleon I dark cloud. This region (roughly 5arcminx5 arcmin ) is characterized by the presence of six ISOCAM-detected young stellar objects (YSOs). Our images have recovered all these sources at near-infrared (near-IR) wavelengths. Ced 110 IRS4, the brightest object in the region, is associated with a remarkable near-IR bipolar nebulosity. Ced 110 IRS6 is resolved in a double system IRS6a and IRS6b with a separation of ~ 2arcsec (~ 320 AU at the distance of the Cha I cloud). We have combined 1.3 mm, far and mid-IR fluxes from the literature with our JHK data and obtained the spectral energy distributions (SEDs) for three (IRS4, IRS6a and ISO-ChaI86) of the six ISOCAM sources in the region. We modelled the SEDs of IRS6a and ISO-ChaI86 with a spherically symmetric dusty envelope, using the DUSTY code. These objects are clear Class I sources of the cloud. Finally, we report the detection of three new objects in this region (NIR 72, 84 and 89) with significant near-IR excess. If these sources are associated with the cloud, the derived luminosities and masses suggest that they are candidate young brown dwarfs of Chamaeleon I. Based on observations collected at the European Southern Observatory, Chile, ESO proposal N.65.I-0054.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
