The VISCACHA survey
Year: 2025
Type: article
Abstract: The extended main-sequence turnoff (eMSTO), a significant broadening of the MSTO region, is a well-known feature observed in young and intermediate-age star clusters. Although prolonged star formation and stellar rotation have been proposed as possible explanations for this extension, no consensus has yet been reached. Most previous studies have focused on high-mass clusters. In this work, we extend the analysis to the less explored low-mass regime by investigating star clusters in the Magellanic Clouds using data from the VISCACHA survey. We employed a widely used method to quantify the MSTO width in terms of age spread. Additionally, to validate our approach, we used a cluster also observed with the HST. Our analysis confirms that the eMSTO phenomenon is also present in low-mass clusters and follows the known age– and mass–MSTO width relations. In particular, the least massive cluster in our sample does not show an eMSTO; this is further evidence in support of the proposed link between the eMSTO and the escape velocity of the cluster and provides a new lower limit to the age spread of 88 ± 40 Myr for the presence of an eMSTO. The consistent MSTO width measurements of the VISCACHA and HST photometries confirm the robustness of our method and demonstrate that the age spread determination is independent of the photometric system, showing also the power of ground-based observations for investigations of the eMSTO phenomenon.
Source: Astronomy and Astrophysics
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,865
Funders: National Science Foundation, U.S. Department of Energy, Michigan State University, Fundação de Amparo à Pesquisa do Estado de São Paulo, Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, Consejo Nacional de Investigaciones Científicas y Técnicas, Ministério da Ciência, Tecnologia e Inovação, Conselho Nacional de Desenvolvimento Científico e Tecnológico, Max-Planck-Gesellschaft, Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro, Universidade Estadual de Santa Cruz, Agencia Nacional de Investigación y Desarrollo, Agencia Nacional de Promoción de la Investigación, el Desarrollo Tecnológico y la Innovación, Max-Planck-Institut für Astronomie, Office of Science, College of Engineering, Michigan State University, University of North Carolina at Chapel Hill, Dirección General de Asuntos del Personal Académico, Universidad Nacional Autónoma de México, SLAC National Accelerator Laboratory
Awards: G1384181827, G1565610166, G1840770272, DECODING THE ACCRETION HISTORY OF THE MILKY WAY WITH THE (SIX) MILLION SPECTROSCOPIC STELLAR CENSUS OF SDSS-V, G2048296361, SCARLET (SMC STAR CLUSTER HISTORY WITH VISCACHA), G2763895450, G2803230404, G2823776494, G2848301204, G3325778992, G3618146566, G3720054464, G376931201, G406816142, G4359570771, CENTRO DE ASTROFISICA Y TECNOLOGIAS AFINES, G4436575305, REDISCOVERING THE MILKY WAY WITH THE VVVX NEAR-INFRARED SURVEY., G4796173437, G5157461147, G5216442843, G5386466380, G5403396360, G5659454435, G5718273138, G5752159476, G5834573078, G6081305029, G6191138830, G65609899, G747722664, G8018385430, CENTRO DE ASTROFISICA Y TECNOLOGIAS AFINES (CATA), G971715606
OpenAlex ID: W4413272906