M83. III - Age and brightness of young and old stellar populations

Abstract

view Abstract Citations (68) References (98) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS M 83 III. Age and brightness of young and old stellar populations. Jensen, E. B. ; Talbot, R. J., Jr. ; Dufour, R. J. Abstract The determination of the luminosities and ages of stellar populations in an external spiral galaxy is considered, and results are presented for the spiral galaxy M83. Procedures used in the deconvolution of the light from the spheroid or bulge, old stellar disk (age greater than 100 million years) and young stellar disk (age less than 100 million years) components of the galaxy are presented, and results are indicated in the form of maps of the luminosity, age and mass distributions of the young population. It is pointed out that although star formation is seen to occur in almost all of the 27 pc resolution pixels within the inner spiral arms, most of the luminosity is confined to associations in aggregates a few hundred pc in size. The ages and positions of these associations indicate a mechanism which globally triggers the formation of massive stars in a well-defined, symmetric two-armed spiral pattern, acts locally in a largely stochastic manner, and terminates after a few tens of millions of years. Results also suggest that the initial mass function in the arms of M83 cannot be represented by a power law over the customary mass range with normal population I stars. Publication: The Astrophysical Journal Pub Date: February 1981 DOI: 10.1086/158640 Bibcode: 1981ApJ...243..716J Keywords: Early Stars; Galactic Structure; Late Stars; Spiral Galaxies; Stellar Evolution; Brightness; Chronology; Hertzsprung-Russell Diagram; Interstellar Extinction; Nuclear Fusion; Ubv Spectra; Astrophysics full text sources ADS | data products NED (8) SIMBAD (1)