Evidence for multiple populations in the intermediate age cluster Lindsay 1 in the SMC

• Verfasst von: Hollyhead, Katie [VerfasserIn]
• Verfasst von: Kacharov, Nikolay [VerfasserIn]
• Verfasst von: Lardo, C. [VerfasserIn]
• Verfasst von: Bastian, Nate [VerfasserIn]
• Verfasst von: Hilker, Michael [VerfasserIn]
• Verfasst von: Koch-Hansen, Andreas [VerfasserIn]
• Verfasst von: Grebel, Eva K. [VerfasserIn]
• Titel: Evidence for multiple populations in the intermediate age cluster Lindsay 1 in the SMC
• Verf.angabe: K. Hollyhead, N. Kacharov, C. Lardo, N. Bastian, M. Hilker, M. Rejkuba, A. Koch, E.K. Grebel and I. Georgiev
• Jahr: 2016
• Umfang: 5 S.
• Fussnoten: Gesehen am 26.10.2017
• Titel Quelle: Enthalten in: De.arxiv.org
• Ort Quelle: [S.l.] : Arxiv.org, 1991
• Jahr Quelle: 2016
• Band/Heft Quelle: (2016), Artikel-ID 1609.01302, Seite 1-5
• Datenträger: Online-Ressource
• Sprache: eng
• Sach-SW: Astrophysics - Astrophysics of Galaxies
• K10plus-PPN: 1564794504

Abstract

Lindsay 1 is an intermediate age (approx 8 Gyr) massive cluster in the Small Magellanic Cloud (SMC). Using VLT FORS2 spectra of 16 probable cluster members on the lower RGB of the cluster, we measure CN and CH band strengths (at 3883 and 4300 Angstroms respectively), along with carbon and nitrogen abundances and find that a sub-population of stars has significant nitrogen enrichment. A lack of spread in carbon abundances excludes evolutionary mixing as the source of this enrichment, so we conclude that this is evidence of multiple populations. Therefore, L1 is the youngest cluster to show such variations, implying that the process triggering the onset of multiple populations must operate until at least redshift ~1.