Rediscovery of the Sixth Star Cluster in the Fornax Dwarf Spheroidal Galaxy

  title={Rediscovery of the Sixth Star Cluster in the Fornax Dwarf Spheroidal Galaxy},
  author={Mei-Yu Wang and Sergey E. Koposov and Alex Drlica-Wagner and A. Pieres and Ting S. Li and Thomas de Boer and Keith C. Bechtol and Vasily A Belokurov and Andrew B. Pace and Timothy M. C. Abbott and James T. Annis and Emmanuel Bertin and David Brooks and Elizabeth Buckley-Geer and David L. Burke and Aurelio Carnero Rosell and Matias Carrasco Kind and Jorge Carretero and Luiz Nicolaci da Costa and Juan de Vicente and Shantanu Desai and H. Thomas Diehl and Peter Doel and Juan Estrada and Brenna L. Flaugher and Pablo Fosalba and Joshua A. Frieman and Juan Garc{\'i}a-Bellido and David W. Gerdes and Daniel Gruen and Robert A. Gruendl and Julia Gschwend and Gaston R. Guti{\'e}rrez and Devon L. Hollowood and Klaus Honscheid and Ben Hoyle and David J. James and Stephen Kent and Kyler W. Kuehn and Nikolay Kuropatkin and Marcio A. G. Maia and Jennifer L. Marshall and Felipe Menanteau and Ramon Miquel and Andreas Alejandro Plazas and Eusebio S{\'a}nchez and Bas{\'i}lio Xavier Santiago and Victor E. Scarpine and Rafe H. Schindler and Michael S. Schubnell and Santiago Serrano and Ignacio Sevilla-Noarbe and M. Smith and R. C. Smith and Flavia Sobreira and Eric Suchyta and Mollye E. C. Swanson and Gregory G. Tarl{\'e} and D. Thomas and Douglas L. Tucker and Alistair R. Walker},
  journal={The Astrophysical Journal Letters},
Since first noticed by Shapley in 1939, a faint object coincident with the Fornax dwarf spheroidal has long been discussed as a possible sixth globular cluster (GC) system. However, debate has continued over whether this overdensity is a statistical artifact or a blended galaxy group. In this Letter we demonstrate, using deep DECam imaging data, that this object is well resolved into stars and is a bona fide star cluster. The stellar overdensity of this cluster is statistically significant at… 

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