Old massive clusters (and a nuclear star cluster?) in the tidal tails of NGC 5238
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 NGC 5238 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, with $M_V=-10.56 0.07$, is as bright as omega Cen, the brightest globular cluster in 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 NGC 5238 that produced the observed tidal tails.
Authors
- M. Correnti
- John M. Cannon (ORCID: https://orcid.org/0000-0002-1821-7019)
- M. Gatto (ORCID: https://orcid.org/0000-0003-4636-6457)
- M. Cignoni (ORCID: https://orcid.org/0000-0001-6291-6813)
- E. Sacchi
- Mariarosa Marinelli (ORCID: https://orcid.org/0000-0002-4775-7292)
- M. Bellazzini (ORCID: https://orcid.org/0000-0001-8200-810X)
- Carlo Nipoti (ORCID: https://orcid.org/0000-0003-3121-6616)
- R. Pascale (ORCID: https://orcid.org/0000-0002-6389-6268)
- F. Annibali (ORCID: https://orcid.org/0000-0003-3758-4516)
- G. Beccari
- A. Aloisi
- Giacomo Bortolini (ORCID: https://orcid.org/0009-0003-6182-8928)
- Lila Schisgal
- M. Tosi (ORCID: https://orcid.org/0000-0003-4050-1769)
Institutions
- University of Pisa (IT)
- Space Telescope Science Institute (US)
- European Southern Observatory (DE)
- Stockholm University (SE)
- Leibniz Institute for Astrophysics Potsdam (DE)
- Astronomical Observatory of Rome (IT)
- Agenzia Spaziale Italiana (IT)
- Astronomical Observatory of Capodimonte (IT)
- Université Bourgogne Franche-Comté (FR)
- AlbaNova (SE)
- Istituto Nazionale di Fisica Nucleare, Sezione di Pisa (IT)
- Osservatorio di Astrofisica e Scienza dello Spazio
- Macalester College (US)
- University of Bologna (IT)
Publication Details
- Journal
- Astronomy and Astrophysics
- Published
- 2024-09-26
- DOI
- https://doi.org/10.1051/0004-6361/202451810
- Primary Topic
- Stellar, planetary, and galactic studies
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- National Aeronautics and Space Administration
- Ohio State University
- California Institute of Technology
- University of Minnesota
- University of Notre Dame
- Arizona Board of Regents
- Space Telescope Science Institute
- European Commission
- Max-Planck-Gesellschaft
- Istituto Nazionale di Astrofisica
- Leibniz-Institut für Astrophysik Potsdam
- Jet Propulsion Laboratory
- Institut sur la Nutrition et les Aliments Fonctionnels
- Leibniz-Gemeinschaft