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تسجيل مستخدم جديدNew infrared star clusters in the Northern and Equatorial Milky Way with 2MASS
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E. Bica
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We carried out a survey of infrared star clusters and stellar groups on the 2MASS J, H and K_s all-sky release Atlas in the Northern and Equatorial Milky Way (350 < l < 360, 0 < l < 230). The search in this zone complements that in the Southern Milky Way (Dutra et al. 2003a). The method concentrates efforts on the directions of known optical and radio nebulae. The present study provides 167 new infrared clusters, stellar groups and candidates. Combining the two studies for the whole Milky Way, 346 infrared clusters, stellar groups and candidates were discovered, whereas 315 objects were previously known. They constitute an important new sample for future detailed studies.
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We carried out a 2MASS J, H and K_s survey of infrared star clusters in the Milky Way sector 230$^{circ}$ $< ell <$ 350$^{circ}$. This zone was the least studied in the literature, previously including only 12 infrared clusters or stellar groups with
$|b|<$ 10$^{circ}$, according to the recent catalogue by Bica et al. (2003). We concentrated efforts on embedded clusters, which are those expected in the areas of known radio and optical nebulae. The present study provides 179 new infrared clusters and stellar groups, which are interesting targets for detailed future infrared studies. The sample of catalogued infrared clusters and stellar groups in the Galaxy is now increased by 63%.
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