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In this paper we present the second and final part of a large and photometrically homogeneous CCD color-magnitude diagram (CMD) data base, comprising 52 nearby Galactic globular clusters (GGC) imaged in the V and I bands. The catalog has…

Astrophysics · Physics 2015-06-24 A. Rosenberg , A. Aparicio , I. Saviane , G. Piotto

We present new BVI photometry for the halo globular cluster M5, and examine the B- and I-band luminosity functions (LFs), based on over 20,000 stars. We do not see evidence in the LF of a ``subgiant excess'' or of a discrepancy in the…

Astrophysics · Physics 2009-10-28 Eric L. Sandquist , Michael Bolte , Peter B. Stetson

The LMC clusters are unique templates of simple stellar population (SSP), being crucial to calibrate models describing the integral light as well as to test the stellar evolution theory. With this in mind we analyzed HST/WFPC2 (V, B--V)…

Astrophysics · Physics 2009-11-13 L. O. Kerber , B. X. Santiago

The clustering of galaxy clusters is a powerful cosmological tool, which can help to break degeneracies between parameters when combined with other cosmological observables. We aim to demonstrate its potential in constraining cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-16 Alessandra Fumagalli , Matteo Costanzi , Alexandro Saro , Tiago Castro , Stefano Borgani

In the present work we analyzed seven globular clusters selected from their location in the Galactic bulge and with metallicity values in the range $-1.30\lesssim\rm{[Fe/H]}\lesssim-0.50$. The aim of this work is first to derive cluster…

I propose and apply a method for deriving ages of the metal-poor globular clusters (GCs) in a distance-independent way, which is based on age indicator related to the main sequence in the two-color diagrams with U-B index. Age of the…

Astrophysics · Physics 2007-05-23 Valery V. Kravtsov

As first Paper of a series devoted to study the old stellar population in clusters and fields in the Small Magellanic Cloud, we present deep observations of NGC121 in the F555W and F814W filters, obtained with the Advanced Camera for…

We use the Binary Population and Spectral Synthesis (BPASS) models to test the recent suggestion that red supergiants can provide an accurate age estimate of a co-eval stellar population that is unaffected by interacting binary stars. Ages…

Solar and Stellar Astrophysics · Physics 2020-04-29 J. J. Eldridge , Emma R. Beasor , N. Britavskiy

In this fourth paper of a series on the precision of ages of stellar populations obtained through the full-spectrum fitting technique, we present a first systematic analysis that compare the age, metallicity and reddening of star clusters…

Astrophysics of Galaxies · Physics 2022-03-21 Randa Asa'd , Paul Goudfrooij , A. M. As'ad

We use ASAD$_2$, the new version of ASAD (Analyzer of Spectra for Age Determination), to obtain the age and reddening of 27 LMC clusters from full fitting of integrated spectra using different statistical methods ($\chi^{2}$ and K-S test)…

Astrophysics of Galaxies · Physics 2016-02-17 Randa S. Asa'd , Alexandre Vazdekis , Sami Zeinelabdin

We report on the properties of 89 low mass star clusters located in the vicinity of luminous young clusters (blue globulars) in the disk of M31. 82 of the clusters are newly detected. We have determined their integrated magnitudes and…

Astrophysics of Galaxies · Physics 2015-05-13 P. W. Hodge , O. K. Krienke , M. Bellazzini , S. Perina , P. Barmby , J. G. Cohen , T. H. Puzia , J. Strader

In this third paper of our series, we present CCD spectrophotometry of 78 star clusters that were detected by Chandar, Bianchi, & Ford in the nearby spiral galaxy M33. CCD images of M33 were obtained as a part of the BATC Color Survey of…

Astrophysics · Physics 2009-11-07 Jun Ma , Xu Zhou , Jiansheng Chen , Hong Wu , Zhaoji Jiang , Suijian Xue , Jin Zhu

In this paper we study the properties of ten halo globular clusters in the nearby spiral galaxy M33. CCD images of M33 were obtained as a part of the BATC Colour Survey of the sky in 13 intermediate-band filters from 3800 to 10000{\AA}. By…

Astrophysics · Physics 2009-11-07 Jun Ma , Xu Zhou , Jiansheng Chen , Hong Wu , Zhaoji Jiang , Suijian Xue , Jin Zhu

We present new high signal-to-noise spectroscopic data on the M31 globular cluster system, obtained with the Hectospec multifiber spectrograph on the 6.5m MMT. More than 300 clusters have been observed at a resolution of 5A. The primary…

Astrophysics of Galaxies · Physics 2015-05-27 Nelson Caldwell , Ricardo Schiavon , Heather Morrison , James A. Rose , Paul Harding

We present new multiband photometry for the Galactic globular cluster IC 4499 extending well past the main sequence turn-off in the U, B, V, R, I, and DDO51 bands. This photometry is used to determine that IC4499 has an age of 12 pm 1 Gyr…

Solar and Stellar Astrophysics · Physics 2015-05-27 A. R. Walker , A. M. Kunder , G. Andreuzzi , A. Di Cecco , P. B. Stetson , M. Monelli , S. Cassisi , G. Bono , R. De Propris , M. Dall'Ora , J. M. Nemec , M. Zoccali

We confirm the existence of a second Large Magellanic Cloud (LMC) star cluster, KMHK 1592, with an age that falls in the middle of the so-called LMC star cluster age gap, a long period of time (~ 4 - 11 Gyr) where no star cluster had been…

Astrophysics of Galaxies · Physics 2022-02-09 Andrés E. Piatti

We present a new method for the evaluation of the age and age-spread among pre-main-sequence (PMS) stars in star-forming regions in the Magellanic Clouds, accounting simultaneously for photometric errors, unresolved binarity, differential…

Astrophysics of Galaxies · Physics 2015-05-19 Nicola Da Rio , Dimitrios A. Gouliermis , Mario Gennaro

We present the first results from the GeMS/GSAOI Galactic Globular Cluster Survey (G4CS) of the Milky-Way globular clusters (GCs) NGC 3201 and NGC 2298. Using the Gemini South Adaptive Optics Imager (GSAOI), in tandem with the Gemini…

Deep CCD photometry down to V=24.5 is presented for the old Magellanic Globular cluster NGC 2257. The main result cna be summarized as follows: i) the RGB Bump has been detected at V=18.7+-0.1, and is compatible with determination of this…

Astrophysics · Physics 2015-06-24 V. Testa , F. R. Ferraro , E. Brocato , V. Castellani

Determination of stellar age is a crucial task in astrophysics research. Different methods are nowadays used either model dependent or based on calibrated empirical relations. The most reliable results are generally obtained when different…

Solar and Stellar Astrophysics · Physics 2021-01-27 Sergio Messina
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