Metal-rich T-dwarfs in the Hyades cluster

TL;DR

This study reports the discovery of the first two brown dwarfs in the Hyades cluster, along with additional low-mass stars, using deep photometric surveys and proper motion analysis to confirm their membership.

Contribution

First identification of brown dwarfs in the Hyades cluster, expanding understanding of substellar objects in this metal-rich, intermediate-age environment.

Findings

Discovered two T-type brown dwarfs in the Hyades

Confirmed 15 low-mass stellar members

Estimated brown dwarf masses around 50 Jupiter masses

Abstract

We present the results of a search for brown dwarfs (BDs) and very low mass (VLM) stars in the 625 Myr-old, metal-rich ([Fe/H]=0.14) Hyades cluster. We performed a deep (I=23, z=22.5) photometric survey over 16 deg$^2$ around the cluster center. We report the discovery of the first 2 BDs in the Hyades cluster, with a spectral type T1 and T2, respectively. Their optical and near-IR photometry, as well as their proper motion, are consistent with them being cluster members. According to models, their mass is about 50 Jupiter masses at an age of 625 Myr. We also report the discovery of 3 new very low mass stellar members and confirm the membership of 15 others.