On a possible origin for the lack of old star clusters in the Small Magellanic Cloud

Abstract

We model the dynamical interaction between the Small and Large Magellanic Clouds and their corresponding stellar cluster populations. Our goal is to explore whether the lack of old clusters ($\gtrsim 7$ Gyr) in the Small Magellanic Cloud (SMC) can be the result of the capture of clusters by the Large Magellanic Cloud (LMC), as well as their ejection due to the tidal interaction between the two galaxies. For this purpose we perform a suite of numerical simulations probing a wide range of parameters for the orbit of the SMC about the LMC. We find that, for orbital eccentricities $e\ge 0.4$, approximately 15 per cent of the SMC clusters are captured by the LMC. In addition, another 20 to 50 per cent of its clusters are ejected into the intergalactic medium. In general, the clusters lost by the SMC are the less tightly bound cluster population. The final LMC cluster distribution shows a spatial segregation between clusters that originally belonged to the LMC and those that were captured from the SMC. Clusters that originally belonged to the SMC are more likely to be found in the outskirts of the LMC. Within this scenario it is possible to interpret the difference observed between the star field and cluster SMC Age-Metallicity Relationships for ages $\gtrsim 7$ Gyr.

5 pages, 3 figures, accepted for publication in MNRAS Letters

References in corpus (4)

• Third-Epoch Magellanic Cloud Proper Motions I: HST/WFC3 data and Orbit Implications
• The age-metallicity relationship of the Large Magellanic Cloud field star population from wide-field Washington photometry
• On spatial distributions of old globular clusters in clusters of galaxies
• Identification of a new relatively old star cluster in the Small Magellanic Cloud

Cited by in corpus (11)

• And yet it moves: The dangers of artificially fixing the Milky Way center of mass in the presence of a massive Large Magellanic Cloud
• SMASH 1: a very faint globular cluster disrupting in the outer reaches of the LMC?
• Two kinematically distinct old globular cluster populations in the Large Magellanic Cloud
• The star cluster frequency throughout the Large Magellanic Cloud
• Accurate radial velocity and metallicity of the Large Magellanic Cloud old globular clusters NGC 1928 and NGC 1939
• A genuine Large Magellanic Cloud age gap star cluster
• Astrophysical properties of newly discovered Magellanic Cloud star clusters
• On the structure of Small Magellanic Cloud star clusters
• First evidence of a stripped star cluster from the Small Magellanic Cloud
• Residual velocities of Small Magellanic Cloud star clusters
• Probing the farthest star clusters to the Small Magellanic Cloud