Astron. Astrophys. 331, 506-518 (1998)

Clusters in the west side of the bar of the Large Magellanic Cloud: interacting pairs?

A. Vallenari ¹, D. Bettoni ¹ and C.Chiosi <sup>2

1</sup> Astronomical Observatory of Padova, Vicolo dell' Osservatorio 5, I-35122 Padua, Italy
² Department of Astronomy of the Padova University, Vicolo dell' Osservatorio 5, I-35122 Padova, Italy (vallenari@astrpd.pd.astro.it)

Received 11 April 1997 / Accepted 16 October 1997

Abstract

In this paper, we present the VI-CCD photometry of 11 unstudied clusters located in the bar of the Large Magellanic Cloud (LMC), as a part of a project aimed to infer the star formation history of this galaxy. We derive the ages of these clusters by means of isochrone fitting. Three close pairs of clusters are included in the sample, namely NGC 1903-SL 357, SL 349-SL 353, SL 387-SL 385. We discuss the surface photometry of these objects: the distortion in the isophotal contours is regarded as a sign of interactions between pairs of physically connected clusters. While the systems SL 349-SL 353 and SL 387-SL 385 are likely pairs of nearly coeval clusters, NGC 1903-SL 357 is not because of the large age difference between the two. Several possible mechanisms for the formation of this peculiar pair are examined in the context of interactions between the Large and Small Magellanic Cloud (SMC).

Key words: Magellanic Clouds galaxies: star clusters galaxies: stellar content Hertzsprung-Russel (HR) diagram

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© European Southern Observatory (ESO) 1998

Online publication: February 16, 1998
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