# JVLA Observations of Young Brown Dwarfs

## TL;DR

This study uses JVLA radio observations to detect and analyze radio emissions from young brown dwarfs and candidates, revealing variability and suggesting some classifications may need revision, while supporting star-like formation processes.

## Contribution

First detailed radio survey of young brown dwarfs showing variability, new detections, and implications for brown dwarf classification and formation mechanisms.

## Key findings

- Detected 49 radio sources, 24 new.
- Observed variability indicating active magnetospheres.
- Supported star-like formation for FU Tau A.

## Abstract

We present sensitive 3.0 cm JVLA radio continuum observations of six regions of low-mass star formation that include twelve young brown dwarfs and four young brown dwarf candidates. We detect a total of 49 compact radio sources in the fields observed, of which 24 have no reported counterparts and are considered new detections. Twelve of the radio sources show variability in timescales of weeks to months, suggesting gyrosynchrotron emission produced in active magnetospheres. Only one of the target brown dwarfs, FU Tau A, was detected. However, we detected radio emission associated with two of the brown dwarf candidates, WL 20S and CHLT 2. The radio flux densities of the sources associated with these brown dwarf candidates are more than an order of magnitude larger than expected for a brown dwarf and suggest a revision of their classification. In contrast, FU Tau A falls on the well-known correlation between radio luminosity and bolometric luminosity, suggesting that the emission comes from a thermal jet and that this brown dwarf seems to be forming as a scaled-down version of low-mass stars.