Details

Autor(en) / Beteiligte

• GOUDFROOIJ, PAUL
• Girardi, Leo
• KOZHURINA-PLATAIS, VERA
• Kalirai, Jason S
• PLATAIS, IMANTS
• PUZIA, THOMAS H
• Correnti, Matteo
• Bressan, Alessandro
• Chandar, Rupali
• Kerber, Leandro
• Marigo, Paola
• RUBELE, STEFANO

Titel

EXTENDED MAIN SEQUENCE TURNOFFS IN INTERMEDIATE-AGE STAR CLUSTERS: A CORRELATION BETWEEN TURNOFF WIDTH AND EARLY ESCAPE VELOCITY

Ist Teil von

• The Astrophysical journal, 2014-12, Vol.797 (1), p.1-21

Ort / Verlag

United States

Erscheinungsjahr

2014

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• We present a color-magnitude diagram analysis of deep Hubble Space Telescope imaging of a mass-limited sample of 18 intermediate-age (1-2 Gyr old) star clusters in the Magellanic Clouds, including eight clusters for which new data were obtained. We evaluate the dynamical evolution of clusters with and without initial mass segregation. Our main results are (1) the fraction of red clump (RC) stars in secondary RCs in eMSTO clusters scales with the fraction of MSTO stars having pseudo-ages of [lap]135 Gyr; (2) the width of the pseudo-age distributions of eMSTO clusters is correlated with their central escape velocity v sub(esc), both currently and at an age of 10 Myr. We find that these two results are unlikely to be reproduced by the effects of interactive binary stars or a range of stellar rotation velocities. The threshold of 12-15 kms super(-1) is consistent with wind velocities of intermediate-mass asymptotic giant branch stars and massive binary stars in the literature.