Facial reconstruction

Search LJMU Research Online

Browse Repository | Browse E-Theses

Chromosome maps of young LMC clusters: An additional case of coeval multiple populations

Saracino, S, Martocchia, S, Bastian, N, Kozhurina-Platais, V, Chantereau, W, Salaris, M, Cabrera-Ziri, I, Dalessandro, E, Kacharov, N, Lardo, C, Larsen, SS and Platais, I (2020) Chromosome maps of young LMC clusters: An additional case of coeval multiple populations. Monthly Notices of the Royal Astronomical Society, 493 (4). pp. 6060-6070. ISSN 0035-8711

Chromosome maps of young LMC clusters an additional case of coeval multiple populations.pdf - Published Version

Download (2MB) | Preview


Recent studies have revealed that the Multiple Populations (MPs) phenomenon does not occur only in ancient and massive Galactic globular clusters (GCs), but it is also observed in external galaxies, where GCs sample a wide age range with respect to the Milky Way. However, for a long time, it was unclear whether we were looking at the same phenomenon in different environments or not. The first evidence that the MPs phenomenon is the same regardless of cluster age and host galaxy came out recently when an intermediate-age cluster from the Small Magellanic Cloud, Lindsay 1, and a Galactic GC have been directly compared. By complementing those data with new images from the Hubble Space Telescope (HST), we extend the comparison to two clusters of different ages: NGC 2121 ($\sim$2.5Gyr) and NGC 1783 ($\sim$1.5Gyr), from the Large Magellanic Cloud. We find a clear correlation between the RGB width in the pseudo-colour $C_{F275W,F343N,F438W}$ and the age of the cluster itself, with the older cluster having larger $\sigma(C_{F275W,F343N,F438W})^{RGB}$ and vice-versa. Unfortunately, the $\sigma$ values cannot be directly linked to the N-abundance variations within the clusters before properly taking account the effect of the first dredge-up. Such HST data also allow us to explore whether multiple star-formation episodes occurred within NGC 2121. The two populations are indistinguishable, with an age difference of only 6$\pm$12 Myr and an initial Helium spread of 0.02 or lower. This confirms our previous results, putting serious constraints on any model proposed to explain the origin of the chemical anomalies in GCs.

Item Type: Article
Additional Information: This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society ©: 2020 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.
Uncontrolled Keywords: astro-ph.SR; astro-ph.SR; astro-ph.GA
Subjects: Q Science > QB Astronomy
Q Science > QC Physics
Divisions: Astrophysics Research Institute
Publisher: Oxford University Press
Related URLs:
Date Deposited: 16 Mar 2020 12:54
Last Modified: 16 Aug 2022 10:00
DOI or ID number: 10.1093/mnras/staa644
URI: https://researchonline.ljmu.ac.uk/id/eprint/12499
View Item View Item