Candidate Milky Way satellites in the Galactic halo

Aims. Sloan Digital Sky Survey (SDSS) DR5 photometric data with 120 ◦ <α <270 ◦ ,2 5 ◦ <δ< 70 ◦ were searched for new Milky Way companions or substructures in the Galactic halo. Methods. Five candidates are identified as overdense faint stellar sources that have color-magnitude diagrams similar to those of known globular clusters, or dwarf spheroidal galaxies. The distance to each candidate is estimated by fitting suitable stellar isochrones to the color-magnitude diagrams. Geometric properties and absolute magnitudes are roughly measured and used to determine whether the candidates are likely dwarf spheroidal galaxies, stellar clusters, or tidal debris. Results. SDSSJ1000+5730 and SDSSJ1329+2841 are probably faint dwarf galaxy candidates while SDSSJ0814+5105, SDSSJ0821+5608, and SDSSJ1058+2843 are very likely extremely faint globular clusters. Conclusions. Follow-up study is needed to confirm these candidates.

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