Probing the Upper Scorpius mass function in the planetary-mass regime
Abstract
We present the results of a deep ZYJ near-infrared survey of 13.5 square degrees in the Upper Scorpius (USco) OB association. We photometrically selected ~100 cluster member candidates with masses in the range 30-5 Jupiters, according to state-of-the-art evolutionary models. We identified 67 ZYJ candidates as bona-fide members, based on complementary photometry and astrometry. We also extracted five candidates detected with VISTA at YJ-only. One is excluded using deep optical z-band imaging, while two are likely non-members, and three remain as potential members. We conclude that the USco mass function is more likely decreasing in the planetary-mass regime (although a flat mass function cannot yet be discarded), consistent with surveys in other regions.
Cite
@article{arxiv.1308.1310,
title = {Probing the Upper Scorpius mass function in the planetary-mass regime},
author = {N. Lodieu and P. D. Dobbie and N. J. G. Cross and N. C. Hambly and M. A. Read and R. P. Blake and D. J. E. Floyd},
journal= {arXiv preprint arXiv:1308.1310},
year = {2015}
}
Comments
Accepted by MNRAS, 10 pages, 4 figures, 4 tables (2 electronic tables). New version with updated figure3 where the (Z-J,Z) colour-magnitude diagram is included