A general catalogue of extended objects in the Magellanic System

TL;DR

This paper updates and expands the catalogues of extended objects in the Magellanic System, including new classifications and detailed spatial analyses, revealing tidal influences and structural profiles of these celestial objects.

Contribution

It provides an updated, comprehensive catalogue of over 9300 objects in the Magellanic System, including new HI shells, with detailed spatial distribution analysis and insights into their tidal and structural properties.

Findings

Objects respond to tidal effects from LMC, SMC, and Bridge.

Number-density profiles fit exponential and core/halo models.

Older star clusters follow an exponential disk distribution.

Abstract

We update the SMC, Bridge, and LMC catalogues of extended objects that were constructed by members of our group from 1995 to 2000. In addition to the rich subsequent literature for the previous classes, we now also include HI shells and supershells. A total of 9305 objects were cross-identified, while our previous catalogues amounted to 7900 entries, an increase of $\approx12%$. We present the results in subcatalogues containing 1445 emission nebulae, 3740 star clusters, 3326 associations, and 794 HI shells and supershells. Angular and apparent size distributions of the extended objects are analysed. We conclude that the objects, in general, appear to respond to tidal effects arising from the LMC, SMC, and Bridge. Number-density profiles extracted along directions parallel and perpendicular to the LMC bar, can be described by two exponential-disks. A single exponential-disk fits the equivalent SMC profiles. Interestingly, when angular-averaged number-densities of most of the extended objects are considered, the profiles of both Clouds do not follow an exponential-disk. Rather, they are best described by a tidally-truncated, core/halo profile, despite the fact that the Clouds are clearly disturbed disks. On the other hand, the older star clusters taken isolately, distribute as an exponential disk. The present catalogue is an important tool for the unambiguous identification of previous objects in current CCD surveys and to establish new findings.