Evidence for two discrete epochs of star formation in the large magellanic cloud

Journal Article · Tue Nov 15 04:00:00 EST 1983 · Astrophys. J., Lett. Ed.; (United States)

DOI:https://doi.org/10.1086/184150· OSTI ID:5144051

Frogel, J A; Blanco, V M

An infrared color-magnitude diagram for an unbiased sample of M giants in a 0.12 deg/sup 2/ field of the Large Magellanic Cloud (LMC) shows the existence of two distinct asymptotic giant branches (AGBs), one of which is 1.5 mag brighter than the other. Stars on the bright AGB are quite similar in color and luminosity to giants in LMC clusters which have ages of about 10/sup 8/ yr; those on the faint AGB look like giants in clusters with ages of a few Gyr. The faint AGB is identified with the star-forming episode found by Butcher and Stryker. The bright AGB is taken to be evidence for a second, discrete episode of star formation corresponding in age to the blue globular clusters in the LMC. At least for main-sequence stars near the turnoff, this recent episode has been only one-tenth as efficient at making stars as was the older episode. The rate of star formation between these two episodes appears to have been significantly lower than in either.

• Research Organization: Cerro Tololo Inter-American Observatory
• OSTI ID: 5144051
• Journal Information: Astrophys. J., Lett. Ed.; (United States), Journal Name: Astrophys. J., Lett. Ed.; (United States) Vol. 274:2; ISSN AJLEA
• 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
CARBON COMPOUNDS
CARBON MONOXIDE
CARBON OXIDES
CHALCOGENIDES
GALAXIES
GIANT STARS
INFRARED SPECTRA
MAGELLANIC CLOUDS
OXIDES
OXYGEN COMPOUNDS
PHOTOMETRY
SPECTRA
STAR ACCRETION
STAR CLUSTERS
STAR EVOLUTION
STARS