Brown Dwarfs in the Pleiades II. A deep optical and near-infrared survey

TL;DR

This study conducts a deep optical and near-infrared survey of the Pleiades cluster to identify brown dwarfs, including the faintest candidate found, and compares the luminosity function to theoretical models.

Contribution

It provides new deep photometric data identifying brown dwarf candidates in the Pleiades, including the lowest mass candidate, and compares observed luminosity functions with models.

Findings

Identification of 8 new brown dwarf candidates, 4 below the brown dwarf limit.

Detection of the lowest mass brown dwarf candidate in the Pleiades to date.

Luminosity function consistent with a power-law mass function index between 0 and 1.

Abstract

The brown dwarf population in the Pleiades cluster has been probed in a deep 850 arcmin2 RIJK survey. The survey is complete to I=21.4 in 76% of the area and to I=20.2 in the remaining 24%. Photometry of 32 previously known members is presented together with 8 new candidates, four of which are below the brown dwarf limit. The faintest one is the lowest mass brown dwarf candidate found hitherto in the Pleiades (I=20.55, 0.04Msun). The derived Pleiades luminosity function is compared to the most recent theoretical mass-luminosity relations and is consistent with a power-law index in the mass function between 0 and 1 to the limit of this survey.