The Next Generation Virgo Cluster Survey: XXXIII. Stellar Population Gradients in the Virgo Cluster Core Globular Cluster System

• Autores: Ko, Youkyung; Peng, Eric W.; Côté, Patrick; Ferrarese, Laura; Liu, Chengze; Longobardi, Alessia; Lançon, Ariane; Muñoz, Roberto P.; Puzia, Thomas H.; Alamo-Martínez, Karla A.; Sales, Laura Virginia; Ramos Almendares, Felipe Alberto; Abadi, Mario Gabriel; Lee, Myung Gyoon; Hwang, Ho Seong; Caldwell, Nelson; Blakeslee, John P.; Boselli, Alessandro; Cuillandre, Jean-Charles; Duc, Pierre-Alain; Eyheramendy, Susana; Guhathakurta, Puragra; Gwyn, Stephen; Jordán, Andrés; Lim, Sungsoon; Sánchez-Janssen, Rubén; Toloba, Elisa
• Año de publicación: 2022
• Idioma: inglés
• Tipo de recurso: artículo
• Materia: Galaxies; Globular clusters; Galaxy clusters
• Institución: Consejo Nacional de Investigaciones Científicas y Técnicas

We present a study of the stellar populations of globular clusters (GCs) in the Virgo Cluster core with a homogeneous spectroscopic catalog of 692 GCs within a major-axis distance R maj = 840 kpc from M87. We investigate radial and azimuthal variations in the mean age, total metallicity, [Fe/H], and α-element abundance of blue (metal-poor) and red (metal-rich) GCs using their co-added spectra. We find that the blue GCs have a steep radial gradient in [Z/H] within R maj = 165 kpc, with roughly equal contributions from [Fe/H] and [α/Fe], and flat gradients beyond. By contrast, the red GCs show a much shallower gradient in [Z/H], which is entirely driven by [Fe/H]. We use GC-tagged Illustris simulations to demonstrate an accretion scenario where more massive satellites (with more metal-and α-rich GCs) sink further into the central galaxy than less massive ones, and where the gradient flattening occurs because of the low GC occupation fraction of low-mass dwarfs disrupted at larger distances. The dense environment around M87 may also cause the steep [α/Fe] gradient of the blue GCs, mirroring what is seen in the dwarf galaxy population. The progenitors of red GCs have a narrower mass range than those of blue GCs, which makes their gradients shallower. We also explore spatial inhomogeneity in GC abundances, finding that the red GCs to the northwest of M87 are slightly more metal-rich. Future observations of GC stellar population gradients will be useful diagnostics of halo merger histories.
Fil: Ko, Youkyung. Korea Astronomy And Space Science Institute; Corea del Sur. Peking University; China
Fil: Peng, Eric W.. Peking University; China
Fil: Côté, Patrick. National Research Council Canada; Canadá
Fil: Ferrarese, Laura. National Research Council Canada; Canadá
Fil: Liu, Chengze. Shanghai Jiao Tong University; China
Fil: Longobardi, Alessia. Università Degli Studi Di Milano-bicocca; Italia
Fil: Lançon, Ariane. Université de Strasbourg; Francia
Fil: Muñoz, Roberto P.. Universidad Católica de Chile; Chile. Pontificia Universidad Católica de Chile; Chile
Fil: Puzia, Thomas H.. Pontificia Universidad Católica de Chile; Chile. Universidad Católica de Chile; Chile
Fil: Alamo-Martínez, Karla A.. Universidad de Guanajuato; México
Fil: Sales, Laura Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; Argentina. University Of California, Riverside; Estados Unidos
Fil: Ramos Almendares, Felipe Alberto. Universidad de La Serena; Chile. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; Argentina
Fil: Abadi, Mario Gabriel. Observatorio Astronomico de la Universidad Nacional de Cordoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; Argentina
Fil: Lee, Myung Gyoon. Seoul National University; Corea del Sur
Fil: Hwang, Ho Seong. Seoul National University; Corea del Sur. Korea Astronomy And Space Science Institute; Corea del Sur
Fil: Caldwell, Nelson. Harvard-Smithsonian Center for Astrophysics; Estados Unidos
Fil: Blakeslee, John P.. Nsf's Noirlab; Estados Unidos
Fil: Boselli, Alessandro. Aix Marseille Université; Francia
Fil: Cuillandre, Jean-Charles. Universite Paris-saclay; Francia
Fil: Duc, Pierre-Alain. Université de Strasbourg; Francia
Fil: Eyheramendy, Susana. Instituto Milenio de Astrofísica; Chile. Universidad Adolfo Ibañez; Chile
Fil: Guhathakurta, Puragra. University of California; Estados Unidos
Fil: Gwyn, Stephen. National Research Council Canada; Canadá
Fil: Jordán, Andrés. Instituto Milenio de Astrofísica; Chile. Universidad Adolfo Ibañez; Chile
Fil: Lim, Sungsoon. Yonsei University; Corea del Sur
Fil: Sánchez-Janssen, Rubén. Royal Observatory; Estados Unidos
Fil: Toloba, Elisa. University Of The Pacific; Estados Unidos