Old massive clusters (and a nuclear star cluster?) in the tidal tails of NGC5238

Bibliographic Details
Title: Old massive clusters (and a nuclear star cluster?) in the tidal tails of NGC5238
Authors: Bellazzini, M., Annibali, F., Correnti, M., Gatto, M., Marinelli, M., Pascale, R., Sacchi, E., Tosi, M., Cignoni, M., Cannon, J. M., Schisgal, L., Bortolini, G., Aloisi, A., Beccari, G., Nipoti, C.
Source: A&A 690, L12 (2024)
Publication Year: 2024
Collection: Astrophysics
Subject Terms: Astrophysics - Astrophysics of Galaxies
More Details: New, deep HST photometry allowed us to identify and study eight compact and bright (M_V< -5.8) star clusters in the outskirts of the star-forming isolated dwarf galaxy NGC5238 (M_*= 10^8 M_sun). Five of these clusters are new discoveries, and six appear projected onto, and/or aligned with the tidal tails recently discovered around this galaxy. The clusters are partially resolved into stars and their colour magnitude diagrams reveal a well developed red giant branch, implying ages older than 1-2~Gyr. Their integrated luminosity and structural parameters are typical of classical globular clusters and one of them has M_V=-10.56 +/- 0.07, as bright as Omega Cen, the brightest globular cluster of the Milky Way. Since the properties of this cluster are in the range spanned by those of nuclear star clusters we suggest that it may be the nuclear remnant of the disrupted satellite of NGC5238 that produced the observed tidal tails.
Comment: Accepted for publication by A&A Letters. Latex, 10 pages, 6 figures, 5 appendices
Document Type: Working Paper
DOI: 10.1051/0004-6361/202451810
Access URL: http://arxiv.org/abs/2409.16436
Accession Number: edsarx.2409.16436
Database: arXiv
More Details
DOI:10.1051/0004-6361/202451810