UNI-MB - logo
UMNIK - logo
 
E-resources
Peer reviewed Open access
  • A search for pre-substellar...
    Palau, Aina; de Gregorio-Monsalvo, I; Morata, Ò; Stamatellos, D; Huélamo, N; Eiroa, C; Bayo, A; Morales-Calderón, M; Bouy, H; Ribas, Á; Asmus, D; Barrado, D

    Monthly notices of the Royal Astronomical Society, 21 August 2012, Volume: 424, Issue: 4
    Journal Article

    Abstract In anattempt to study whether the formation of brown dwarfs (BDs) takes place as a scaled-down version of low-mass stars, we conducted Institut de Radioastronomie Millimetrique (IRAM) 30 m/MAMBO-II observations at 1.2 mm in a sample of 12 proto-BD candidates selected from Spitzer/IRAC data in the B213-L1495 clouds in Taurus. Subsequent observations with the Caltech Submillimetre Observatory at 350 μm, Very Large Array at 3.6 and 6 cm, and IRAM 30 m/EMIR in the 12CO (1-0), 13CO (1-0) and N2H+ (1-0) transitions were carried out towards the two most promising Spitzer/IRAC source(s), J042118 and J041757. J042118 is associated with a compact (<10 arcsec or <1400 au) and faint source at 350 μm, while J041757 is associated with a partially resolved (∼16 arcsec or ∼2000 au) and stronger source emitting at centimetre wavelengths with a flat spectral index. The corresponding masses of the dust condensations are ∼1 and 5 M Jup for J042118 and J041757, respectively. In addition, about 40 arcsec to the north-east of J041757, we detect a strong and extended submillimetre source, J041757-NE, which is not associated with near-infrared/far-infrared emission down to our detection limits, but is clearly detected in 13CO and N2H+ at ∼7 km s−1, and for which we estimated a total mass of ∼100 M Jup, close to the mass required to be gravitationally bound. In summary, our observational strategy has allowed us to find in B213-L1495 two proto-BD candidates and one pre-substellar core candidate, whose properties seem to be consistent with a scaled-down version of low-mass stars.