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We present an automated statistical method that uses medium-resolution spectroscopic observations of a set of stars to select those that show evidence of possessing significant amounts of neutron-capture elements. Our tool was tested…

天体物理仪器与方法 · 物理学 2019-10-30 G. Navó , J. L. Tous , J. M. Solanes

We have derived Mn abundances for more than 200 stars in 19 globular clusters. In addition, Mn abundance determinations have been made for a comparable number of halo field and disk stars possessing an overlapping range of metallicities and…

天体物理学 · 物理学 2008-11-26 J. S. Sobeck , I. I. Ivans , J. A. Simmerer , C. Sneden , P. Hoeflich , J. P. Fulbright , R. P. Kraft

The vast volume of data generated by modern astronomical surveys offers test beds for the application of machine-learning. It is important to evaluate potential existing tools and determine those that are optimal for extracting scientific…

天体物理仪器与方法 · 物理学 2019-09-04 Rafael Garcia-Dias , Carlos Allende Prieto , Jorge Sánchez Almeida , Pedro Alonso Palicio

We present new observations of the lensing cluster SMACSJ2031.8-4036 obtained with the MUSE integral field spectrograph as part of its commissioning on the Very Large Telescope. By providing medium-resolution spectroscopy over the full…

宇宙学与河外天体物理 · 物理学 2015-06-22 J. Richard , V. Patricio , J. Martinez , R. Bacon , B. Clement , P. Weilbacher , K. Soto , L. Wisotzki , J. Vernet , R. Pello , J. Schaye , M. Turner , T. Martinsson

Recent studies have shown that the extended main-sequence turn off (eMSTO) is a common feature of intermediate-age star clusters in the Magellanic Clouds (MCs). The most simple explanation is that these stellar systems harbor multiple…

太阳与恒星天体物理 · 物理学 2015-05-27 A. P. Milone , L. R. Bedin , G. Piotto , A. F. Marino , S. Cassisi , A. Bellini , H. Jerjen , A. Pietrinferni , A. Aparicio , R. M. Rich

We present an analysis of the multiple stellar populations of the globular cluster NGC 1851. We used lower resolution spectra of giant stars to measure CN, CH, and calcium H & K spectral indices, and determine elemental abundances for…

太阳与恒星天体物理 · 物理学 2016-10-31 Jeffrey D. Simpson , Sarah L. Martell , Colin A. Navin

We present the results of our investigation on the phenomenon of mass segregation in young star clusters in the Magellanic Clouds. HST/WFPC2 observations on NGC 1818, NGC 2004 & NGC 2100 in the Large Magellanic Cloud and NGC 330 in the…

天体物理学 · 物理学 2009-11-10 D. Gouliermis , S. C. Keller , M. Kontizas , E. Kontizas , I. Bellas-Velidis

We used a combination of optical and near-UV Hubble Space Telescope photometry and FLAMES/ESO-VLT high-resolution spectroscopy to characterize the stellar content of the old and massive globular cluster (GC) NGC121 in the Small Magellanic…

太阳与恒星天体物理 · 物理学 2016-10-05 E. Dalessandro , E. Lapenna , A. Mucciarelli , L. Origlia , F. R. Ferraro , B. Lanzoni

We have used high-resolution spectra obtained with the multifiber facility FLAMES at the Very Large Telescope of the European Southern Observatory to derive kinematic properties and chemical abundances of Fe, O, Mg and Si for 89 stars in…

星系天体物理 · 物理学 2012-11-26 Emilio Lapenna , Alessio Mucciarelli , Livia Origlia , Francesco R. Ferraro

We report on the magnitude of the intrinsic [Fe/H] spread in the Small Magellanic Cloud (SMC) intermediate-age massive clusters NGC 339, 361, Lindsay 1 and 113, respectively. In order to measure the cluster metallicity dispersions, we used…

星系天体物理 · 物理学 2018-11-09 Andrés E. Piatti

This paper presents the chemical abundance analysis of a sample of 27 red giant stars located in 4 popolous intermediate-age globular clusters in the Large Magellanic Cloud, namely NGC 1651, 1783, 1978 and 2173. This analysis is based on…

天体物理学 · 物理学 2009-11-13 A. Mucciarelli , E. Carretta , L. Origlia , F. R. Ferraro

Recently, a noticeable number of new star clusters was identified in the outskirts of the Large Magellanic Cloud (LMC) populating the so-called star cluster age gap, a space of time (~ 4-12 Gyr) where the only known star cluster is…

星系天体物理 · 物理学 2021-03-31 Andrés E. Piatti

The metallicity spread, or the metallicity trend along the evolutionary sequence of a globular cluster, is a rich source of information to help understand the cluster physics (e.g. multiple populations) and stellar physics (e.g. atomic…

太阳与恒星天体物理 · 物理学 2022-05-25 Martina Baratella , Deepthi S. Prabhu , Luiz A. Silva-Lima , Philippe Prugniel

We present our new, fully-automated method to detect and measure the ages of star clusters in nearby galaxies, where individual stars can be resolved. The method relies purely on statistical analysis of observations and Monte-Carlo…

NGC1850 is the nearest Young Massive Cluster of the Local Group with a mass similar to those of Galactic globular clusters. Recent studies have revealed an extended morphology of its MSTO, which can be interpreted as a spread in either age…

太阳与恒星天体物理 · 物理学 2022-05-04 A. Sollima , V. D'Orazi , R. Gratton , R. Carini , E. Carretta , A. Bragaglia , S. Lucatello

We have introduced a semi-automated quantitative method to estimate the age and reddening of 1072 star clusters in the Large Magellanic Cloud (LMC) using the Optical Gravitational Lensing Experiment (OGLE) III survey data. This study brings…

星系天体物理 · 物理学 2016-08-24 P. K. Nayak , A. Subramaniam , S. Choudhury , G. Indu , Ram Sagar

We present Washington system colour-magnitude diagrams (CMDs) for 17 practically unstudied star clusters located in the bar as well as in the inner disc and outer regions of the Large Magellanic Cloud (LMC). Cluster sizes were estimated…

太阳与恒星天体物理 · 物理学 2015-06-24 Tali Palma , Juan J. Clariá , Doug Geisler , Luciana V. Gramajo , Andrea V. Ahumada

Stars with unusual elemental abundances offer clues about rare astrophysical events or nucleosynthetic pathways. Stars with significantly depleted magnesium and enhanced potassium ([Mg/Fe] < -0.5; [K/Fe] > 1) have to date only been found in…

Context. We use Hubble Space Telescope photometry of six rich, compact star clusters in the Large Magellanic Cloud (LMC), with ages ranging from 0.01 to 1.0 Gyr, to derive the clusters' stellar mass functions (MFs) at their half-mass radii.…

太阳与恒星天体物理 · 物理学 2015-05-13 Q. Liu , R. de Grijs , L. C. Deng , Y. Hu , S. F. Beaulieu

Mass loss is a key property to understand stellar evolution and in particular for low-metallicity environments. Our knowledge has improved dramatically over the last decades both for single and binary evolutionary models. However, episodic…