New brown dwarf candidates in the Pleiades

We have performed deep, wide-field imaging on a ∼ 0.4 deg² field in the Pleiades (Melotte 22). The selected field was not yet target of a deep search for low mass stars and brown dwarfs. Our limiting magnitudes are R∼22 mag and I∼20 mag, sufficient to detect brown dwarf candidates down to 40 M_J. We found 197 objects, whose location in the (I, R-I) color magnitude diagram is consistent with the age and the distance of the Pleiades. Using CTK R and I as well as JHK photometry from our data and the 2MASS survey we were able to identify 7 new brown dwarf candidates. We present our data reduction technique, which enables us to resample, calibrate, and co-add many images by just two steps. We estimate the interstellar extinction and the spectral type from our optical and the NIR data using a two-dimensional χ² fitting.

Based on observations obtained with telescopes of the University Observatory Jena, which is operated by the Astrophysical Institute of the Friedrich- Schiller-University.

Table A3 is available at the CDS via http://cdsarc.u-strasbg.fr/pub/cats/J/AN/330/439...