Bibcode
Casewell, S. L.; Dobbie, P. D.; Hodgkin, S. T.; Moraux, E.; Jameson, R. F.; Hambly, N. C.; Irwin, J.; Lodieu, N.
Bibliographical reference
Monthly Notices of the Royal Astronomical Society, Volume 378, Issue 3, pp. 1131-1140.
Advertised on:
7
2007
Citations
49
Refereed citations
43
Description
We present the results of a deep optical-near-infrared (optical-NIR)
multi-epoch survey covering 2.5 deg2 of the Pleiades open
star cluster to search for new very low-mass brown dwarf members. A
significant (~5 yr) epoch difference exists between the optical (CFH12k
I-, Z-band) and NIR (UKIRT WFCAM J-band) observations. We construct I, I
- Z and Z, Z - J colour-magnitude diagrams to select candidate cluster
members. Proper motions are computed for all candidate members and
compared to the background field objects to further refine the sample.
We recover all known cluster members within the area of our survey. In
addition, we have discovered nine new candidate brown dwarf cluster
members. The seven faintest candidates have red Z - J colours and show
blue NIR colours. These are consistent with being L- and T-type Pleiads.
Theoretical models predict their masses to be around 11MJup.