A multi-wavelength characterization of proto-brown dwarf candidates in Serpens

TL;DR

This study uses multi-wavelength observations and modeling to identify and characterize proto-brown dwarf candidates in Serpens, revealing their evolutionary stages and potential to become brown dwarfs.

Contribution

It provides the first detailed multi-wavelength characterization and classification of proto-brown dwarf candidates in Serpens, including their evolutionary stages and mass estimates.

Findings

Identified four proto-brown dwarf candidates with low luminosities.

Two candidates are in early evolutionary stages (Stage 0/I), while two are more evolved (Stage I-T/Flat).

Approximately 20% of sources initially classified as protostars are actually edge-on disk systems.

Abstract

We present results from a deep sub-millimeter survey in the Serpens Main and Serpens/G3-G6 clusters, conducted with the Submillimetre Common-User Bolometer Array (SCUBA-2) at the James Clerk Maxwell Telescope. We have combined Herschel PACS far-infrared photometry, sub-millimeter continuum and molecular gas line observations, with the aim to conduct a detailed multi-wavelength characterization of `proto-brown dwarf' candidates in Serpens. We have performed continuum and line radiative transfer modeling, and have considered various classification schemes to understand the structure and the evolutionary stage of the system. We have identified four proto-brown dwarf candidates, of which the lowest luminosity source has an Lbol ~0.05 Lsun. Two of these candidates show characteristics consistent with Stage 0/I systems, while the other two are Stage I-T/Class Flat systems with tenuous envelopes. Our work has also revealed a ~20% fraction of mis-identified Class 0/I/Flat sources that show characteristics consistent with Class II edge-on disk systems. We have set constraints on the mass of the central object using the measured bolometric luminosities and numerical simulations of stellar evolution. Considering the available gas+dust mass reservoir and the current mass of the central source, three of these candidates are likely to evolve into brown dwarfs.