English

Early Planet Formation in Embedded Disks (eDisk). XI. A high-resolution view toward the BHR 71 Class 0 protostellar wide binary

Earth and Planetary Astrophysics 2024-07-25 v1 Solar and Stellar Astrophysics

Abstract

We present Atacama Large Millimeter/submillimeter Array (ALMA) observations of the binary Class 0 protostellar system BHR 71 IRS1 and IRS2 as part of the Early Planet Formation in Embedded Disks (eDisk) ALMA Large Program. We describe the 12^{12}CO (JJ=2--1), 13^{13}CO (JJ=2--1), C18^{18}O (JJ=2--1), H2_2CO (J=32,1J=3_{2,1}--22,02_{2,0}), and SiO (JJ=5--4) molecular lines along with the 1.3 mm continuum at high spatial resolution (\sim0.08" or \sim5 au). Dust continuum emission is detected toward BHR 71 IRS1 and IRS2, with a central compact component and extended continuum emission. The compact components are smooth and show no sign of substructures such as spirals, rings or gaps. However, there is a brightness asymmetry along the minor axis of the presumed disk in IRS1, possibly indicative of an inclined geometrically and optically thick disk-like component. Using a position-velocity diagram analysis of the C18^{18}O line, clear Keplerian motions were not detected toward either source. If Keplerian rotationally-supported disks are present, they are likely deeply embedded in their envelope. However, we can set upper limits of the central protostellar mass of 0.46 M_\odot and 0.26 M_\odot for BHR 71 IRS1 and BHR 71 IRS2, respectively. Outflows traced by 12^{12}CO and SiO are detected in both sources. The outflows can be divided into two components, a wide-angle outflow and a jet. In IRS1, the jet exhibits a double helical structure, reflecting the removal of angular momentum from the system. In IRS2, the jet is very collimated and shows a chain of knots, suggesting episodic accretion events.

Keywords

Cite

@article{arxiv.2407.17249,
  title  = {Early Planet Formation in Embedded Disks (eDisk). XI. A high-resolution view toward the BHR 71 Class 0 protostellar wide binary},
  author = {Sacha Gavino and Jes K. Jørgensen and Rajeeb Sharma and Yao-Lun Yang and Zhi-Yun Li and John J. Tobin and Nagayoshi Ohashi and Shigehisa Takakuwa and Adele Plunkett and Woojin Kwon and Itziar de Gregorio-Monsalvo and Zhe-Yu Daniel Lin and Alejandro Santamaría-Miranda and Yusuke Aso and Jinshi Sai and Yuri Aikawa and Kengo Tomida and Patrick M. Koch and Jeong-Eun Lee and Chang Won Lee and Shih-Ping Lai and Leslie W. Looney and Suchitra Narayanan and Nguyen Thi Phuong and Travis J. Thieme and Merel L. R. van 't Hoff and Jonathan P. Willians and Hsi-Wei Yen},
  journal= {arXiv preprint arXiv:2407.17249},
  year   = {2024}
}

Comments

38 pages, 29 figures, accepted in ApJ