Probing the Upper Scorpius mass function in the planetary-mass regime★

Autor: Nigel Hambly, Mike Read, David J. E. Floyd, R. Blake, Nicholas Cross, Nicolas Lodieu, Paul Dobbie
Rok vydání: 2013
Předmět:
Zdroj: Monthly Notices of the Royal Astronomical Society. 435:2474-2482
ISSN: 1365-2966
0035-8711
DOI: 10.1093/mnras/stt1460
Popis: 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.
Comment: 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
Databáze: OpenAIRE