English

The Kinematic and Dynamic Properties of HBC 494's Wide-Angle Outflows

Solar and Stellar Astrophysics 2024-02-05 v2 Astrophysics of Galaxies

Abstract

We present Atacama Large Millimeter/sub-millimeter Array (ALMA) Cycle-5 observations of HBC 494, as well as calculations of the kinematic and dynamic variables which represent the object's wide-angle bipolar outflows. HBC 494 is a binary FU Orionis type object located in the Orion A molecular cloud. We take advantage of combining the ALMA main array, Atacama Compact Array (ACA), and Total Power (TP) array in order to map HBC 494's outflows and thus, estimate their kinematic parameters with higher accuracy in comparison to prior publications. We use 12^{12}CO, 13^{13}CO, C18^{18}O and SO observations to describe the object's outflows, envelope, and disc, as well as estimate the mass, momentum, and kinetic energy of the outflows. After correcting for optical opacity near systemic velocities, we estimate a mass of 3.0×1023.0\times10^{-2} M_{\odot} for the southern outflow and 2.8×1022.8\times10^{-2} M_{\odot} for the northern outflow. We report the first detection of a secondary outflow cavity located approximately 1515" north of the central binary system, which could be a remnant of a previous large-scale accretion outburst. Furthermore, we find CO spatial features in HBC 494's outflows corresponding to position angles of 35\sim35^{\circ} and 145\sim145^{\circ}. This suggests that HBC 494's outflows are most likely a composite of overlapping outflows from two different sources, i.e., HBC 494a and HBC 494b, the two objects in the binary system.

Keywords

Cite

@article{arxiv.2401.03282,
  title  = {The Kinematic and Dynamic Properties of HBC 494's Wide-Angle Outflows},
  author = {Austen Fourkas and Dary Ruiz-Rodriguez and Lee G. Mundy and Jonathan P. Williams},
  journal= {arXiv preprint arXiv:2401.03282},
  year   = {2024}
}

Comments

26 pages, 24 figures, accepted to MNRAS