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Candidate Milky Way Satellites in the Galactic Halo

C. Liu·J. Hu·H. Newberg·Y. Zhao
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Abstract

Sloan Digital Sky Survey (SDSS) DR5 photometric data with $120^{\circ} < α< 270^{\circ}$, $25^{\circ} < δ< 70^{\circ}$ are searched for new Milky Way companions or substructures in the Galactic halo. Five candidates are identified as overdensities of 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. SDSSJ1000+5730 and SDSSJ1329+2841 are likely faint dwarf galaxy candidates while SDSSJ0814+5105, SDSSJ0821+5608 and SDSSJ1058+2843 are likely extremely faint globular clusters. Follow-up study is needed to confirm these candidates.

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C. Liu, J. Hu, H. Newberg, Y. Zhao. 2007-10-19. Candidate Milky Way Satellites in the Galactic Halo. https://arxiv.org/abs/astro-ph/0612173

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