|EPoS 2020 Suggested Contribution|
The bipolar molecular outflow of the very low mass star Par-Lup3-4: Evidence for scaled down low-mass star formation
ESO, Santiago, CL
Very low-mass star have been studied in detail and displayed jets and outflow that seem a scaled-down version of those detected in low-mass stars. However, the number of well characterized outflows in very low-mass sources is still very low. The properties of molecular outflows are linked with the formation of the sources, that in the case of very low-mass stars can be explained by brown dwarf formation theories. Then, the very low-mass regime can serve as a bridge between low-mass star formation and brown dwarf formation.
We study the bipolar molecular outflow of the very low-mass star Par-Lup3-4, a 0.12 Msol object known to power an optical jet. We observed Par-Lup3-4 with ALMA in Bands 6 and 7, both at the continuum, and CO molecular gas. In particular, we studied three different CO isotopologues, CO (3-2), 13CO (3-2) and CO(2-1)
Our observations reveal for the first time the base of a bipolar molecular outflow in a very low-mass star, as well as a secondary structure moving perpendicular to the primary outflow. The primary outflow morphology is consistent with the jet orientation and disk inclination. The outflow mass is 9.5×10-7 Msol with an outflow rate of 4.3×10-9 Msol/yr. A new fitting to the SED suggests that Par-Lup3-4 can be a binary system. We have characterized Par-Lup3-4 in detail, and its properties are consistent with those reported in other very low-mass sources. This sources provides further evidence for very low-mass sources forming as a scaled-down version of low-mass star formation.
|Caption: Bipolar outflow cavity of Par-Lup3-4. White contours represent the CO(3-2) emission line. Green contours are the ALMA continuum image at 0.89 mm. Background color image is the [SII] optical jet from Comeron & Fernandez 2011.|
I. De Gregorio-Montalvo, ESO, CL
N. Huelamo, CAB (INTA-CSIC), ES
A.L. Plunkett, NRAO, US
A. Ribas, ESO, CL
F. Comeron, ESO, DE
M.R. Schreiber, U Valparaiso, CL
C. Lopez, JAO, CL
K. Muzic, CENTRA, PT