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Related papers: Metallicity Estimates for Old Star Clusters in M33

200 papers

This paper presents 3600-5400 Angstroms integrated spectra of 19 globular clusters (or candidates) projected on the central regions of M31, r <=5.3 arcmin (approx 1.2 kpc). We check the cluster nature of these objects, and derive their…

Astrophysics · Physics 2007-05-23 P. Jablonka , E. Bica , C. Bonatto , T. J. Bridges , M. Langlois , D. Carter

We present a new technique for the determination of age and metallicity in composite stellar populations using Stromgren filters. Using principal component (PC) analysis on multi-color models, we isolate the range of values necessary to…

Astrophysics · Physics 2009-11-10 K. Rakos , J. Schombert

The ages and metallicities of globular clusters play an important role not just in testing models for their formation and evolution but in understanding the assembly history for their host galaxies. Here we use a combination of imaging and…

Astrophysics of Galaxies · Physics 2024-01-26 Christopher Usher , Nelson Caldwell , Ivan Cabrera-Ziri

We investigate the color-magnitude distribution in the rich cluster AC 118 at z=0.31. The sample is selected by the photometric redshift technique, allowing to study a wide range of properties of stellar populations, and is complete in the…

Astrophysics · Physics 2009-11-07 P. Merluzzi , F. La Barbera , M. Massarotti , G. Busarello , M. Capaccioli

Globular cluster ages are more than just lower limits to the age of the universe; the distribution of ages constraints the timescales for galaxy formation and chemical evolution. Globular cluster populations with different metallicities…

Astrophysics · Physics 2007-05-23 Pauline Barmby

We derive stellar ages, from evolutionary tracks, and metallicities, from Stromgren photometry, for a sample of 5828 dwarf and sub-dwarf stars from the Hipparcos Catalogue. This stellar disk sample is used to investigate the age-metallicity…

Astrophysics · Physics 2009-11-07 Sofia Feltzing , Johan Holmberg , Jarrod R. Hurley

We investigate, on the basis of CCD Stroemgren photometry, the ages and metallicities of six LMC clusters together with their surrounding field population. The clusters and metallicities are: NGC1651 (in the range [Fe/H]=-0.65 dex to -0.41…

Astrophysics · Physics 2007-05-23 B. Dirsch , T. Richtler , W. P. Gieren , M. Hilker

The large majority of extragalactic star cluster studies performed to date essentially use multi-colour photometry, combined with theoretical stellar synthesis models, to derive ages, masses, extinction estimates, and metallicities. M31…

Astrophysics · Physics 2009-11-11 Z. Fan , J. Ma , R. de Grijs , Y. Yang , X. Zhou

We derive ages, metallicities and [alpha/Fe] ratios from the integrated spectra of 23 globular clusters in M31, by employing multivariate fits to two stellar population models. In parallel we analyze spectra of 21 Galactic globular clusters…

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

Context: The formation and evolution of disk galaxies are long standing questions in Astronomy. Understanding the properties of globular cluster systems can lead to important insights on the evolution of its host galaxy. Aims: We aim to…

Astrophysics of Galaxies · Physics 2015-06-12 Enio Cezario , Paula R. T. Coelho , Alan Alves-Brito , Duncan A. Forbes , Jean P. Brodie

Red giants are an excellent tool for probing the history of star formation and subsequent metallicity evolution in the galaxies. The well-defined red giant branch (RGB) stars of the globular clusters can be used to determine their slopes…

Astrophysics of Galaxies · Physics 2024-06-17 Saurabh Sharma , Jura Borissova

Red clump (RC) stars are widely used as an excellent standard candle. To make them even better, it is important to know the dependence of their absolute magnitudes on age and metallicity. We observed star clusters in the Large Magellanic…

Solar and Stellar Astrophysics · Physics 2019-05-08 Hiroki Onozato , Yoshifusa Ita , Yoshikazu Nakada , Shogo Nishiyama

We present integrated-light spectra of 8 Young Massive Clusters (YMCs) in the metal-rich spiral galaxy NGC 5236 (M 83). The observations were taken with the X-Shooter spectrograph on the ESO Very Large Telescope. Through the use of…

Astrophysics of Galaxies · Physics 2017-11-01 Svea Hernandez , Søren Larsen , Scott Trager , Lex Kaper , Paul Groot

The observed characteristics of globular cluster (GC) systems, such as metallicity distributions, are commonly used to place constraints on galaxy formation models. However, obtaining reliable metallicity values is particularly difficult…

Astrophysics of Galaxies · Physics 2019-07-10 Alexa Villaume , Aaron J. Romanowsky , Jean Brodie , Jay Strader

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

This is the second of a series of papers in which we present a new solution to reconcile the prediction of single stellar population (SSP) models with the observed stellar mass-to-light ($M/L$) ratios of globular clusters (GCs) in M31 and…

Astrophysics of Galaxies · Physics 2017-04-11 Hosein Haghi , Pouria Khalaj , Akram Hasani Zonoozi , Pavel Kroupa

We present precision radial velocities and stellar population parameters for 77 star clusters in the Local Group galaxy M33. Our GTC and WHT observations sample both young, massive clusters and known/candidate globular clusters, spanning…

Astrophysics of Galaxies · Physics 2015-04-24 Michael A. Beasley , Izaskun San Roman , Carme Gallart , Ata Sarajedini , Antonio Aparicio

Omega Centauri is a peculiar Globular Cluster formed by a complex stellar population. To shed light on this, we studied 172 stars belonging to the 5 SGBs that we can identify in our photometry, in order to measure their [Fe/H] content as…

Astrophysics of Galaxies · Physics 2015-06-22 S. Villanova , D. Geisler , R. G. Gratton , S. Cassisi

Globular Cluster Systems (GCSs) of most early-type galaxies feature two peaks in their optical colour distributions. Blue-peak GCs are believed to be old and metal-poor, whereas the ages, metallicities, and the origin of the red-peak GCs…

Astrophysics · Physics 2009-12-04 R. Kotulla , U. Fritze , P. Anders