An extreme paucity of second population AGB stars in the ‘normal’ globular cluster M4
نویسندگان
چکیده
منابع مشابه
Hst Photometry of the Globular Cluster M4
This paper presents a detailed description of the acquisition and processing of a large body of imaging data for three fields in the globular cluster M4 taken with the Wide Field and Planetary Camera 2 aboard the Hubble Space Telescope. Analysis with the ALLFRAME package yielded the deepest photometry yet obtained for this cluster. The resulting data-set for 4708 stars (positions and calibrated...
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We discuss three aspects of post-AGB (PAGB) stars in old populations. (1) HST photometry of the nucleus of the planetary nebula (PN) K 648 in the globular cluster (GC) M15 implies a mass of 0.60 M , in contrast to the mean masses of white dwarfs in GCs of ∼0.5M . This suggests that K 648 is descended from a merged binary, and we infer that single Pop II stars do not produce visible PNe. (2) Yel...
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ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society: Letters
سال: 2016
ISSN: 1745-3925,1745-3933
DOI: 10.1093/mnrasl/slw073