Discovery of new Milky Way star cluster candidates in the 
2 MASS point source catalog. V. Follow-up observations of the young 
stellar cluster candidates RCW 87, [BDSB2003] 164 and [DBSB2003] 172

We analyse star cluster properties in the nearby spiral galaxy M33, combining our extensive HST WFPC2 photometry and ground-based follow up spectroscopy. These data show that cluster velocity dispersion increases with age. Simulations comparing synthetic disk and halo populations with observations indicate a composite disk/halo system for the old M33 clusters. The best fit fraction of 85 ± 5% halo plus 15 ± 5% disk differs from that found in the Milky Way, where ∼ 30% of the globular clusters are metal rich objects associated with the bulge and/or thick disk. Spectroscopic line indices for a halo subsample (17 objects) reveal an age spread of ∼ 5 — 7 Gyr, and little progression in metal abundance with age. This is consistent with a chaotic formation for a substantial portion of the M33 halo, and also consistent with an accretion origin for a large number of the halo clusters.

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The (quite dark) stellar cluster around the supermassive black hole Sagittarius A* at the center of the Milky Way

Proceedings of the International Astronomical Union ◽

10.1017/s1743921308017663 ◽

2007 ◽

Vol 3 (S245) ◽

pp. 207-210

Author(s):

Rainer Schödel ◽

A. Eckart

Keyword(s):

Black Hole ◽

Adaptive Optics ◽

Near Infrared ◽

Milky Way ◽

Infrared Imaging ◽

Current Theory ◽

Star Cluster ◽

Massive Black Hole ◽

Stellar Cluster ◽

Sagittarius A

AbstractHigh-resolution seeing limited and adaptive optics near-infrared imaging observations of the stellar cluster within about one parsec of the massive black hole Sagittarius A* allow us to obtain a detailed picture of the structure of the nuclear star cluster of the Milky Way. We find that the stellar number counts and the diffuse light of the unresolved stellar population can be described very well by a stellar density function in the form of a broken-power law. This agrees well with theoretical predictions on the structure of a dynamically relaxed star cluster around a massive black hole. However, the cusp slope is found to be too shallow, which may be related to mixing of different stellar populations and continuous star formation, phenomena that are not taken into account by current theory. Mass densities larger than 107 solar masses per pc3 are reached within 0.1 pc of the central black hole. Intriguingly, up to several tens of percent of the total cluster mass in the central parsec may be in the form of dark stellar remnants.

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DISCOVERY OF A FAINT OUTER HALO MILKY WAY STAR CLUSTER IN THE SOUTHERN SKY

The Astrophysical Journal ◽

10.1088/0004-637x/803/2/63 ◽

2015 ◽

Vol 803 (2) ◽

pp. 63 ◽

Cited By ~ 66

Author(s):

Dongwon Kim ◽

Helmut Jerjen ◽

Antonino P. Milone ◽

Dougal Mackey ◽

Gary S. Da Costa

Keyword(s):

Milky Way ◽

Star Cluster

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NEP-WIDE POINT SOURCE CATALOG

Publications of The Korean Astronomical Society ◽

10.5303/pkas.2012.27.4.147 ◽

2012 ◽

Vol 27 (4) ◽

pp. 147-148

Author(s):

Seong Jin Kim ◽

Hyung Mok Lee ◽

NEP-Wide Team NEP-Wide Team

Keyword(s):

Point Source ◽

Point Source Catalog

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Surface Distribution of M Stars With Different IRAS Colour

International Astronomical Union Colloquium ◽

10.1017/s0252921100093416 ◽

1988 ◽

Vol 108 ◽

pp. 50-50

Author(s):

Keiichi Ishida ◽

Mazlan Othman

Keyword(s):

Point Source ◽

Interstellar Extinction ◽

Circumstellar Dust ◽

Dust Shell ◽

Surface Distribution ◽

Sky Survey ◽

M Stars ◽

Point Source Catalog ◽

K Band

The surface distribution of M stars is studied by differentiating them according to whether they show a circumstellar dust shell (CS) or not. Analysis shows that galactic latitudinal and longitudinal distributions are not determined by spectral subclasses alone. The study also indicates that the M type stars with CS have higher intrinsic luminosities in the K band than those without CS. The M stars used in the study are obtained from the Two Micron Sky Survey catalogue (IRC) which is an unbiased sample with respect to the interstellar extinction. The CS feature is identified by the ratio of flux densities at 12 and 25 μm in the IRAS point source catalog.

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Constraints on radio source clustering towards galaxy clusters: application for cm-wavelength simulations of blind sky surveys

Proceedings of the International Astronomical Union ◽

10.1017/s1743921316010048 ◽

2014 ◽

Vol 11 (S308) ◽

pp. 301-302

Author(s):

Bartosz Lew

Keyword(s):

Point Source ◽

Radio Source ◽

Galaxy Clusters ◽

Sky Surveys ◽

Source Confusion ◽

Point Source Catalog

AbstractWe derive constraints on radio source clustering towards Planck-selected galaxy clusters using the NVSS point source catalog. The constraint can be used for making a more realistic Sunyaev-Zeldovich effect (SZE) mocks, calculating predictions of detectable clusters count and for quantifying source confusion in radio surveys.

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