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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.
The number of low-mass brown dwarfs and even free floating planetary mass objects in young nearby star-forming regions and associations is continuously increasing, offering the possibility to study the low-mass end of the IMF in greater detail. In th
Four Class I maser sources were detected at 44, 84, and 95 GHz toward chemically rich outflows in the regions of low-mass star formation NGC 1333I4A, NGC 1333I2A, HH25, and L1157. One more maser was found at 36 GHz toward a similar outflow, NGC 2023.
(Abridged) Disks are observed around pre-main sequence stars, but how and when they form is still heavily debated. While disks around young stellar objects have been identified through thermal dust emission, spatially and spectrally resolved molecula
A survey of young bipolar outflows in regions of low-to-intermediate-mass star formation has been carried out in two class I methanol maser transitions: 7_0-6_1A+ at 44 GHz and 4_{-1}-3_0E at 36 GHz. We detected narrow features towards NGC 1333I2A, N
We present the results of a single dish survey toward 95 VeLLOs in optically thick (HCN 1-0) and thin ($rm N_2H^+$ 1-0) lines performed for the purpose of understanding the physical processes of inward motions in the envelopes of the VeLLOs and chara