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Related papers: M31 globular cluster metallicities and ages

200 papers

We present a new technique to determine age and metallicity of old stellar populations (globular clusters and elliptical galaxies) using an iterative principal component analysis on narrow band (Str\"omgren) colors. Our technique is capable…

Astrophysics · Physics 2009-11-11 K. Rakos , J. Schombert , A. Odell

This paper addresses the questions of what we have learned about how and when dense star clusters form, and what studies of star clusters have revealed about galaxy formation and evolution. One important observation is that globular…

Astrophysics · Physics 2007-05-23 Stephen E. Zepf

We discuss recent developments on the age and metallicity distribution for early type galaxies in different environments.

Astrophysics · Physics 2008-11-07 Duncan A. Forbes , Alejandro I. Terlevich

Globular clusters are the oldest objects in the Galaxy whose age may be accurately determined. As such globular cluster ages provide the best estimate for the age of the universe. The age of a globular cluster is determined by a comparison…

Astrophysics · Physics 2009-10-28 Brian Chaboyer

Globular cluster systems in most large galaxies display bimodal color and metallicity distributions, which are frequently interpreted as indicating two distinct modes of cluster formation. The metal-rich (red) and metal-poor (blue) clusters…

Astrophysics of Galaxies · Physics 2015-05-14 Oleg Y. Gnedin

Some of the most massive globular clusters of our Milky Way, such as for example omega-Centauri, show a mixture of stellar populations spanning a few Gyr in age and 1.5 dex in metallicities. In contrast, standard formation scenarios predict…

Astrophysics · Physics 2009-11-11 Mike Fellhauer , Pavel Kroupa , Wyn Evans

The distribution of galaxy properties in groups and clusters holds important information on galaxy evolution and growth of structure in the Universe. While clusters have received appreciable attention in this regard, the role of groups as…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 J. Trevor Mendel , Robert N. Proctor , Jesper Rasmussen , Sarah Brough , Duncan A. Forbes

We present a metallicity distribution based on photometry and spectra for 442 omega Cen cluster members that lie at the main sequence turnoff region of the color-magnitude diagram. This distribution is similar to that found for the red…

Astrophysics · Physics 2011-02-11 L. M. Stanford , G. S. Da Costa , J. E. Norris , R. D. Cannon

This review focuses on how galaxies and their globular cluster systems form. I first discuss the now fairly convincing evidence that some globular clusters form in galaxy starbursts/mergers. One way these observations are valuable is they…

Astrophysics · Physics 2007-05-23 Stephen E. Zepf

We review the properties of globular clusters which make them useful for studying the Galactic halo, Galactic chemical evolution, and the early stages of the formation of the Milky Way. We review the evidence that GCs have a chemical…

Astrophysics of Galaxies · Physics 2015-05-14 Judith G. Cohen

The bimodal metallicity distribution of globular clusters (GCs) in massive galaxies implies two distinct sub-populations: metal-poor and metal-rich. Using the recent data of \textit{Gaia} we highlighted three distinct dissimilarities…

Astrophysics of Galaxies · Physics 2024-10-22 Ali Rostami-Shirazi , Akram Hasani Zonoozi , Hosein Haghi , Malihe Rabiee

Their ubiquity and extreme densities make star clusters probes of prime importance of galaxy evolution. Old globular clusters keep imprints of the physical conditions of their assembly in the early Universe, and younger stellar objects,…

Astrophysics of Galaxies · Physics 2018-05-02 Florent Renaud

In a series of three papers, we introduced a novel cluster formation model that describes the formation, growth, and disruption of star clusters in high-resolution cosmological simulations. We tested this model on a Milky Way-sized galaxy…

Astrophysics of Galaxies · Physics 2020-03-18 Hui Li , Oleg Gnedin

Ages have been derived for 55 globular clusters (GCs) from overlays of isochrones onto the turnoff photometry, assuming distances based on fits of zero-age horizontal branch (ZAHB) models to the lower bound of the observed distributions of…

Astrophysics of Galaxies · Physics 2013-10-14 Don A. Vandenberg , Karsten Brogaard , Ryan Leaman , Luca Casagrande

Metal-rich (red) globular clusters in massive galaxies are, on average, smaller than metal-poor (blue) globular clusters. One of the possible explanations for this phenomenon is that the two populations of clusters have different spatial…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Jeremy J. Webb , William E. Harris , Alison Sills

We present results derived from VLT-FORS2 spectra of 24 different globular clusters associated with the lenticular galaxy NGC3115. A subsample of 17 globular clusters have sufficiently high signal-to-noise to allow precision measurements of…

Astrophysics · Physics 2009-11-07 Harald Kuntschner , Bodo L. Ziegler , R. M. Sharples , Guy Worthey , Klaus J. Fricke

We are using full spectrum fitting to determine the ages and metallicities of Galactic clusters (M67 and globular clusters). We find that the method is very accurate to measure the metallicity. Blue horizontal branches are well identified…

Astrophysics · Physics 2009-11-13 Mina Koleva , Philippe Prugniel , Pierre Ocvirk , Damien Le Borgne

We present detailed chemical abundances for $>$20 elements in $\sim$30 globular clusters in M31. These results have been obtained using high resolution ($\lambda/\Delta\lambda\sim$24,000) spectra of their integrated light and analyzed using…

Astrophysics of Galaxies · Physics 2022-10-26 J. E. Colucci , R. A. Bernstein , J. Cohen

Old, metal-poor globular clusters trace the formation and evolution of early-type galaxies. Their are the best probes, at low redshift, of the building-up of galaxy halos at high redshift. Their properties constrain the characteristics of…

Astrophysics · Physics 2009-11-07 Markus Kissler-Patig

Globular cluster systems exhibit a bewildering variety of characteristics. No single scenario appears to be able to account for the wide range of specific globular cluster frequencies that are observed in galaxies of various types. The…

Astrophysics · Physics 2009-10-31 Sidney van den Bergh
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