Two class I very low-mass objects in Taurus

Abstract

We report our study of two proto-brown dwarf candidates in Taurus, [GKH94]~41 and IRAS~04191+1523B. Based on continuum maps at 102~GHz (or 2.9~mm), spectral types and the spectral energy distribution of both targets, we confirmed the class I evolutionary stage of [GKH94]~41 and IRAS~04191+1523B, and estimated the upper limit to the final masses to be 49$^{+56}_{-27}$~$M_{\rm J}$ and 75$^{+40}_{-26}$~$M_{\rm J}$ for [GKH94]~41 and IRAS~04191+1523B, respectively. This indicates that they will likely end up as brown dwarfs or very low-mass stars. The existence of these class I very low-mass objects strongly supports the scenario that brown dwarfs and very low-mass stars have the same formation stages as low-mass stars.