FIRST DETECTION OF THERMAL RADIOJETS IN A SAMPLE OF PROTO-BROWN DWARF CANDIDATES

Journal Article · Wed Jul 01 04:00:00 EDT 2015 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/807/1/55· OSTI ID:22522222

Morata, Oscar ^[1]; Palau, Aina; González, Ricardo F. ^[2]; Gregorio-Monsalvo, Itziar de ^[3]; Ribas, Álvaro ^[4]; Perger, Manuel ^[5]; Bouy, Hervé; Barrado, David; Huélamo, Nuria; Morales-Calderón, María ^[6]; Eiroa, Carlos ^[7]; Bayo, Amelia ^[8]; others, and

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1. Institute of Astronomy and Astrophysics, Academia Sinica, P.O. Box 23-141, Taipei 106, Taiwan (China)
2. Centro de Radioastronomía y Astrofísica, Universidad Nacional Autónoma de México, P.O. Box 3-72, 58090 Morelia, Michoacán, México (Mexico)
3. Joint ALMA Observatory (JAO), Alonso de Córdova 3107, Vitacura, Santiago (Chile)
4. European Space Astronomy Centre (ESA), P.O. Box 78, E-28691 Villanueva de la Cañada, Madrid (Spain)
5. Institut de Ciències de l’Espai (CSIC-IEEC), Campus UAB—Facultat de Ciències, Torre C5—parell 2, E-08193 Bellaterra, Catalunya (Spain)
6. Centro de Astrobiología, INTA-CSIC, Dpto.Astrofísica, ESAC Campus, P.O. Box 78, E-28691 Villanueva de la Cañada, Madrid (Spain)
7. Departamento de Física Teórica, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco, E-28049 Madrid (Spain)
8. Max Planck Institut für Astronomie, Königstuhl 17, D-69117, Heidelberg (Germany)

We observed with the Jansky Very Large Array at 3.6 and 1.3 cm a sample of 11 proto-brown dwarf (BD) candidates in Taurus in a search for thermal radio jets driven by the most embedded BDs. We detected for the first time four thermal radio jets in proto-BD candidates. We compiled data from UKIDSS, 2MASS, Spitzer, WISE, and Herschel to build the spectral energy distribution (SED) of the objects in our sample, which are similar to typical Class I SEDs of young stellar objects (YSOs). The four proto-BD candidates driving thermal radio jets also roughly follow the well-known trend of centimeter luminosity against bolometric luminosity determined for YSOs, assuming they belong to Taurus, although they present some excess of radio emission compared to the known relation for YSOs. Nonetheless, we are able to reproduce the flux densities of the radio jets modeling the centimeter emission of the thermal radio jets using the same type of models applied to YSOs, but with corresponding smaller stellar wind velocities and mass-loss rates, and exploring different possible geometries of the wind or outflow from the star. Moreover, we also find that the modeled mass outflow rates for the bolometric luminosities of our objects agree reasonably well with the trends found between the mass outflow rates and bolometric luminosities of YSOs, which indicates that, despite the “excess” centimeter emission, the intrinsic properties of proto-BDs are consistent with a continuation of those of very low-mass stars to a lower mass range. Overall, our study favors the formation of BDs as a scaled-down version of low-mass stars.

• OSTI ID: 22522222
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 807; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
BOLOMETERS
COMPARATIVE EVALUATIONS
COSMIC RADIO SOURCES
ENERGY SPECTRA
FLUX DENSITY
JETS
LUMINOSITY
MASS TRANSFER
PROTOSTARS
STARS
STELLAR WINDS