A molecular outflow driven by the brown dwarf binary FU Tau

TL;DR

This paper reports the detection of a molecular outflow driven by the brown dwarf binary FU Tau, marking it as the third brown dwarf with observed outflow activity, and provides estimates of outflow properties.

Contribution

First detection of a molecular outflow from FU Tau, a brown dwarf binary, expanding understanding of outflow phenomena in substellar objects.

Findings

Detected bipolar outflow via CO(2-1) emission

Estimated outflow mass at 4 x 10^-6 solar masses

Estimated outflow rate at 6 x 10^-10 solar masses per year

Abstract

We report the detection of a molecular outflow driven by the brown dwarf binary FU Tau. Using the IRAM 30 m telescope we observed the $^{12}$CO(2-1) (CO) emission in the vicinity of FU Tau and detected a bipolar outflow by examining the wings of the CO(2-1) line as we moved away from the source position. An integrated map of the wing emission between 3 kms$^{-1}$ and 5 kms$^{-1}$ reveals a blue-shifted lobe at a position of $\sim$ 20 \arcsec\ from the FU Tau system and at a position angle of $\sim$ 20$^{\circ}$. The beam size of the observations is $11\arcsec$\ hence it is not possible to distinguish between the two components of the FU Tau binary. However as optical forbidden emission, a strong tracer of the shocks caused by outflow activity, has been detected in the spectrum of FU Tau A we assume this component to be the driving source of the molecular outflow. We estimate the mass and mass outflow rate of the outflow at 4 $\times$ 10$^{-6}$ \Msun\ and 6 $\times$ 10$^{-10}$ \Msun/yr respectively. These results agree well with previous estimates for BD molecular outflows. FU Tau A is now the third BD found to be associated with molecular outflow activity and this discovery adds to the already extensive list of the interesting properties of FU Tau.