Abstract

view Abstract Citations (55) References (41) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS On the Horizontal Branch and the Helium Content of 47 Tucanae Dorman, Ben ; Vandenberg, Don A. ; Laskarides, P. G. Abstract Theoretical sequences of horizontal branch models, constructed using a new algorithm for the treatment of semiconvection, are described. The adopted composition parameters were chosen to bracket the ranges in metallicity and helium abundance appropriate to the globular cluster NGC 104 (47 Tucanae). By fitting the theoretical models to recent CCD photometry of the cluster, it is found that, on standard assumptions, its initial helium content must have been close to 24 percent by mass. In addition, best fits show that models for Fe/H = -0.65 provide an excellent match to the horizontal branch, if (m - M)v of about 13.44, and thereby yield consistency over the entire color-magnitude diagram of the cluster. This result reinforces the present age determination of about 13.5 Gyr for 47 Tuc. Publication: The Astrophysical Journal Pub Date: August 1989 DOI: 10.1086/167746 Bibcode: 1989ApJ...343..750D Keywords: Helium; Horizontal Branch Stars; Stellar Composition; Stellar Evolution; Abundance; Globular Clusters; Astrophysics; CLUSTERS: GLOBULAR; STARS: ABUNDANCES; STARS: EVOLUTION; STARS: HORIZONTAL-BRANCH; STARS: INTERIORS full text sources ADS | data products SIMBAD (3)

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.