Results 1 to 10 of about 50 (49)
Young Star Clusters: Progenitors of Globular Clusters!? [PDF]
Highlights of Astronomy, 2005 AbstractStar cluster formation is a major mode of star formation in the extreme conditions of interacting galaxies and violent starbursts. Young clusters are observed to form in a variety of such galaxies, a substantial number resembling the progenitors of globular clusters in mass and size, but with significantly enhanced metallicity.
Anders, Peter +2 more
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Blue hook stars in globular clusters [PDF]
Monthly Notices of the Royal Astronomical Society: Letters, 2009 Abstract Blue hook (BHk) stars are a rare class of horizontal branch stars that have so far been found in only very few Galactic globular clusters (GCs). The dominant mechanism for producing these objects is currently still unclear.
Dieball, A. +6 more
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Massive Stars and Globular Cluster Formation [PDF]
The Astrophysical Journal, 2007 We first present chemodynamical simulations to investigate how stellar winds of massive stars influence early dynamical and chemical evolution of forming globular clusters (GCs). In our numerical models, GCs form in turbulent,high-density giant molecular clouds (GMCs), which are embedded in a massive dark matter halo at high redshifts. We show how high-
Bekki, Kenji, Chiba, Masashi
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Axial Rotation of Globular Star Clusters [PDF]
Nature, 1936 THE axial rotation of globular star clusters has not yet been measured, so far as we know, from the differences of radial velocities at their opposite edges, but indirect evidence of their rotation is the observed ellipticity. The oblateness e of a rotating body depends on the ratio of the centrifugal force to the gravity at the star's surface ; that ...
Kopal, Zdeněk, Slouka, Hubert
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Probing the Faintest Stars in a Globular Star Cluster [PDF]
Science, 2006 NGC 6397 is the second closest globular star cluster to the Sun. Using 5 days of time on the Hubble Space Telescope, we have constructed an ultradeep color-magnitude diagram for this cluster. We see a clear truncation in each of its two major stellar sequences.
Richer, Harvey B. +12 more
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Rotation in Globular Cluster stars [PDF]
Astronomy & Astrophysics, 2003 We present a derivation of upper limits to the rotation of Main Sequence stars in three globular clusters using spectra obtained during time allocated to the ESO Large Programs 165-L0263 and 167.D-0173, with UVES at VLT2 (Kueyen). The stars analyzed in this work do not show any evidence of high values of rotational velocities as far as the outer layers
S. Lucatello, R. G. Gratton
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Neutron Stars in Globular Clusters [PDF]
Proceedings of the International Astronomical Union, 2007 AbstractDynamical interactions that occur between objects in dense stellar systems are particularly important for the question of formation of X-ray binaries. We present results of numerical simulations of 70 globular clusters with different dynamical properties and a total stellar mass of 2×107M⊙.
Ivanova, Natalia +2 more
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Nature, 1888 PHYSICAL aggregations of stars may be broadly divided into “globular” and “irregular” clusters. Although, as might have been expected, the line of demarcation between the two classes is by no means sharply drawn, each has its own marked peculiarities. We shall limit our attention, in the present article, to the first kind.
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Accretion of gas by globular cluster stars [PDF]
Astronomy & Astrophysics, 2002 11 pages; accepted for publication in Astronomy and ...
Thoul, Anne +6 more
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VARIABLE STARS IN THE GLOBULAR CLUSTER NGC 2808 [PDF]
The Astronomical Journal, 2013 The first calibrated broadband BVI time-series photometry is presented for the variable stars in NGC 2808, with observations spanning a range of twenty-eight years. We have also redetermined the variability types and periods for the variable stars identified previously by Corwin et al, revising the number of probable fundamental-mode RR Lyrae variables
Kunder, Andrea +4 more
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