Nine new open clusters within 500 pc from the sun
<i>Aims. <i/>One of the results of the Milky Way Star Clusters (MWSC) survey was the detection of a slight under-density of old (ca. 1 Gyr) clusters within the nearest kilo-parsec from the Sun. This under-density may be due to an ineffectiveness in the detection of larger structures with...
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| Main Authors: | , , |
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| Format: | Article (Journal) |
| Language: | English |
| Published: |
24 October 2016
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| In: |
Astronomy and astrophysics
Year: 2016, Volume: 595 |
| ISSN: | 1432-0746 |
| DOI: | 10.1051/0004-6361/201629158 |
| Online Access: | Verlag, kostenfrei, Volltext: http://dx.doi.org/10.1051/0004-6361/201629158
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| Author Notes: | Siegfried Röser, Elena Schilbach, and Bertrand Goldman |
| Summary: | <i>Aims. <i/>One of the results of the Milky Way Star Clusters (MWSC) survey was the detection of a slight under-density of old (ca. 1 Gyr) clusters within the nearest kilo-parsec from the Sun. This under-density may be due to an ineffectiveness in the detection of larger structures with lower surface brightness. We report on our attempts to reveal such clusters. <i>Methods. <i/>We derived proper motions from a combination of Tycho-2 with URAT1, and obtained a mean precision of about 1.4 mas/yr per co-ordinate for 1.3 million stars north of −20° declination. We cut the sky into narrow proper motion slices and searched for spatial over-densities of stars in each slice. We then examined stars from over-densities in optical and near-infrared colour-magnitude diagrams to determine if they are compatible with isochrones of a cluster. We estimated the field star contamination using our data and the Besançon Galactic model.<i>Results. <i/>We detected nine hitherto unknown open clusters in the vicinity of the Sun with ages between 70 Myr and 1 Gyr, and distances between 200 and 500 pc. |
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| Item Description: | Gesehen am 30.10.2017 |
| Physical Description: | Online Resource |
| ISSN: | 1432-0746 |
| DOI: | 10.1051/0004-6361/201629158 |