Evolutionary population synthesis in stellar systems. I. A global approach

Journal Article · Fri Dec 01 04:00:00 EST 1989 · Astrophysical Journal, Supplement Series; (USA)

DOI:https://doi.org/10.1086/191399· OSTI ID:6967139

Buzzoni, A ^[1]

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1. Osservatorio Astronomico di Brera, Milan (Italy)

A new grid of 450 theoretical models for old simple stellar populations is presented. Evolutionary synthesis explores the influence of relevant parameters such as age, chemical composition, initial mass function, and stellar mass loss, on the integrated spectral energy distribution. Ages range between 4 and 18 Gyr, and the metallicity Z ranges from 0.0001 to 0.03, with helium content Y = 0.23 and 0.25, respectively. Three values are considered for the initial mass function, assumed as a power law, N(M) proportional to M exp-s; s = 1.35, 2.35, and 3.35. The computational code takes into account in a quantitative way the contributions from all the relevant stellar evolutionary phases according to the theory of the stellar evolution. Thus, late stage in the life of low- mass stars, such as the horizontal branch and the asymptotic and postasymptotic giant branches are accounted for. Furthermore, a simplified treatment for the evolution of the horizontal branch is developed, and the influence of different morphologies are investigated. 109 refs.

• OSTI ID: 6967139
• Journal Information: Astrophysical Journal, Supplement Series; (USA), Journal Name: Astrophysical Journal, Supplement Series; (USA) Vol. 71; ISSN APJSA; ISSN 0067-0049
• Country of Publication: United States
• Language: English

Related Subjects

640102* -- Astrophysics & Cosmology-- Stars & Quasi-Stellar
Radio & X-Ray Sources
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
AGE ESTIMATION
CHEMICAL COMPOSITION
ENERGY SPECTRA
GIANT STARS
MASS
MASS TRANSFER
MATHEMATICAL MODELS
MORPHOLOGY
RED GIANT STARS
SPECTRA
SPECTROPHOTOMETRY
STAR EVOLUTION
STAR MODELS
STARS