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Title: OPEN CLUSTERS IN THE MILKY WAY OUTER DISK: NEWLY DISCOVERED AND UNSTUDIED CLUSTERS IN THE SPITZER GLIMPSE-360, CYG-X, AND SMOG SURVEYS

Open stellar clusters are extremely valuable probes of Galactic structure, star formation, kinematics, and chemical abundance patterns. Near-infrared (NIR) data have enabled the detection of hundreds of clusters hidden from optical surveys, and mid-infrared (MIR) data are poised to offer an even clearer view into the most heavily obscured parts of the Milky Way. We use new MIR images from the Spitzer GLIMPSE-360, Cyg-X, and SMOG surveys to visually identify a large number of open cluster candidates in the outer disk of the Milky Way (65 Degree-Sign < l < 265 Degree-Sign ). Using NIR color-magnitude diagrams, stellar isochrones, and stellar reddening estimates, we derive cluster parameters (metallicity, distance, reddening) for those objects without previous identification and/or parameters in the literature. In total, we present coordinates and sizes of 20 previously unknown open cluster candidates; for 7 of these we also present metallicity, distance, and reddening values. In addition, we provide the first estimates of these values for nine clusters that had been previously cataloged. We compare our cluster sizes and other derived parameters to those in the open cluster catalog of Dias et al. and find strong similarities except for a higher mean reddening for our objects, which signifiesmore » our increased detection sensitivity in regions of high extinction. The results of this cluster search and analysis demonstrate the ability of MIR imaging and photometry to augment significantly the current census of open clusters in the Galaxy.« less
Authors:
 [1] ; ; ; ;  [2] ; ; ; ;  [3] ;  [4] ;  [5]
  1. Department of Astronomy, Ohio State University, Columbus, OH 43210 (United States)
  2. Department of Astronomy, University of Virginia, Charlottesville, VA 22904 (United States)
  3. Department of Astronomy, University of Wisconsin-Madison, Madison, WI 53706 (United States)
  4. Department of Physics, University of Wisconsin-Whitewater, Whitewater, WI 53190 (United States)
  5. Department of Physics, Manchester College, North Manchester, IN 46962 (United States)
Publication Date:
OSTI Identifier:
22136552
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astronomical Journal (New York, N.Y. Online); Journal Volume: 146; Journal Issue: 3; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CATALOGS; COLOR; DISTANCE; INFRARED SURVEYS; MILKY WAY; NEAR INFRARED RADIATION; PHOTOMETRY; SENSITIVITY; STAR CLUSTERS; STARS