2006/10/12 by Benjamin F. Williams, Robin Ciardullo, Patrick R. Durrell +17 · 3 citations
Medicine · Physics and Astronomy · #Advanced Camera for Surveys #Astronomy #Astronomy and Astrophysical Research #Astrophysics #Astrophysics and Star Formation Studies #Blue straggler #Galaxy #Galaxy cluster #Globular cluster #Intracluster medium #Medicine #Metallicity #Physics #Population #Red-giant branch #Star formation #Stars #Stellar, planetary, and galactic studies #Virgo Cluster #astro-ph
paper · pdf · doi:10.1086/510149
published as Astrophys.J.656:756-769,2007 · 36 pages, 1 table, 13 figures (resolution lowered for Figs. 4, 6, and 7), accepted for publication in ApJ
arxiv created 2006/10/12 · openalex publication_date 2007/02/14 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We have used the Hubble Space Telescope 's Advanced Camera for Surveys (ACS) to detect and measure ~5300 stars in a single intracluster field in the Virgo Cluster. By performing F606W and F814W photometry on these stars, we have determined their metallicity distribution function and constrained the types of stars present in this portion of Virgo's intracluster space. Based on the small number of stars detected that were brighter than the red giant branch (RGB) tip, we suggest that in this region, Virgo's intracluster stars are mostly old (≳10 Gyr). Through analysis of the RGB stars themselves, we determine that the population contains the full range of metallicities probed (-2.3 ≤ [M/H] ≤ 0.0). We also present evidence that the younger (≤10 Gyr) component of the population is more metal-rich, with [M/H] > -0.5. The spatial distribution of the most metal-poor stars in the field shows significantly more structure than that of the metal-rich stars, indicating that the intracluster population is not well mixed. We discuss the implications that these observations have for the production of intracluster stars and the dynamical evolution of the Virgo Cluster.