Discovery of Asymmetric Spike-like Structures of the 10 au Disk around the Very Low-luminosity Protostar Embedded in the Taurus Dense Core MC 27/L1521F with ALMA

• DOI: 10.3847/1538-4357/ad2f9a
• Publication Date: 2024-04-11T07:59:06Z
• Authors: Kazuki Tokuda; Naoto Harada; Mitsuki Omura; Tomoaki Matsumoto; Toshikazu Onishi; Kazuya Saigo; Ayumu Shoshi; Shingo Nozaki; Kengo Tachihara; Naofumi Fukaya; Yasuo Fukui; Shu-ichiro Inutsuka; Masahiro N. Machida
• Keywords: Protostar; Submillimeter Array; Young stellar object

Abstract Recent Atacama Large Millimeter/submillimeter Array (ALMA) observations have revealed an increasing number of compact protostellar disks with radii less than a few tens astronomical units and that young Class 0/I objects intrinsic size diversity. To deepen our understanding the origin such tiny disks, we performed highest-resolution configuration ALMA at beam ∼0.″03 (4 au) on very low-luminosity 0 protostar embedded in Taurus dense core MC 27/L1521F. The 1.3 mm continuum measurement successfully resolved tiny, faint (∼1 mJy) disk major axis length ∼10 au, one smallest examples studies. In addition, detected spike-like components northeastern direction edge. Gravitational instability or other fragmentation mechanisms cannot explain structures, given central stellar mass ∼0.2 M ⊙ ≳10 −4 . Instead, propose these small spike structures were formed by recent dynamic magnetic flux transport event due to interchange would be favorable occur if parental has strong field. presence complex arc-like larger (∼2000 scale same as suggests was not single. Such episodic, dynamical events may play important role maintaining nature gas envelope during main accretion phase.