A photometric and astrometric investigation of the brown dwarfs in Blanco 1

Abstract

We present the results of a photometric and astrometric study of the low mass stellar and substellar population of the young open cluster Blanco 1. We have exploited J band data, obtained recently with the Wide Field Camera (WFCAM) on the United Kingdom InfraRed Telescope (UKIRT), and 10 year old I and z band optical imaging from CFH12k and Canada France Hawaii Telescope (CFHT), to identify 44 candidate low mass stellar and substellar members, in an area of 2 sq. degrees, on the basis of their colours and proper motions. This sample includes five sources which are newly discovered. We also confirm the lowest mass candidate member of Blanco 1 unearthed so far (29MJup). We determine the cluster mass function to have a slope of alpha=+0.93, assuming it to have a power law form. This is high, but nearly consistent with previous studies of the cluster (to within the errors), and also that of its much better studied northern hemisphere analogue, the Pleiades.

8 Pages, 5 Figures, 2 Tables and 1 Appendix. Accepted for publication in MNRAS

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Cited by in corpus (7)

• NGTS clusters survey. I. Rotation in the young benchmark open cluster Blanco 1
• Diagnosing the Stellar Population and Tidal Structure of the Blanco1 Star Cluster
• Evaluating Gyrochronology on the Zero-Age-Main-Sequence: Rotation Periods in the Southern Open Cluster Blanco 1 from the KELT-South Survey
• The family pictures of our neighbours: investigating the mass function and dynamical parameters of nearby open clusters
• Proper Motion of the Draco Dwarf Galaxy from Subaru Suprime-Cam Data
• NGTS clusters survey -- III: A low-mass eclipsing binary in the Blanco 1 open cluster spanning the fully convective boundary
• Confirming the least massive members of the Pleiades star cluster