ALMA reveals a pseudo-disc in a proto-brown dwarf

B. Riaz, M. N. Machida, D. Stamatellos

研究成果: Contribution to journalArticle査読

5 被引用数 (Scopus)


We present the observational evidence of a pseudo-disc around the proto-brown dwarf Mayrit 1701117, the driving source of the large-scale HH 1165 jet. Our analysis is based on Atacama Large Millimeter/submillimeter Array 12CO (2-1) line and 1.37 mm continuum observations at an angular resolution of ∼0.4 arcsec. The pseudo-disc is a bright feature in the CO position-velocity diagram, elongated in a direction perpendicular to the jet axis, with a total (gas+dust) mass of ∼0.02 M, size of 165-192 au, and a velocity spread of ±2 km s-1. The large velocity gradient is a combination of infalling and rotational motions, indicating a contribution from a pseudo-disc and an unresolved inner Keplerian disc. There is weak emission detected in the H2CO (3-2) and N2D+ (3-2) lines. H2CO emission likely probes the inner Keplerian disc where CO is expected to be frozen, while N2D+ possibly originates from an enhanced clump at the outer edge of the pseudo-disc. We have considered various models (core collapse, disc fragmentation, circumbinary disc) that can fit both the observed CO spectrum and the position-velocity offsets. The observed morphology, velocity structure, and the physical dimensions of the pseudo-disc are consistent with the predictions from the core collapse simulations for brown dwarf formation. From the best model fit, we can constrain the age of the proto-brown dwarf system to be ∼30 000-40 000 yr. A comparison of the H2 column density derived from the CO line and 1.37 mm continuum emission indicates that only about 2 per cent of the CO is depleted from the gas phase.

ジャーナルMonthly Notices of the Royal Astronomical Society
出版ステータス出版済み - 7 1 2019

All Science Journal Classification (ASJC) codes

  • Astronomy and Astrophysics
  • Space and Planetary Science

フィンガープリント 「ALMA reveals a pseudo-disc in a proto-brown dwarf」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。