Variable Red Giants--The MACHO View

Conference · Fri Jan 03 04:00:00 EST 2003

OSTI ID:15003141

Keller, S C; Cook, K H

The authors present a study of the MACHO red variable population in the Large Magellanic Cloud. This study reveals six period-luminosity relations among the red variable population. Only two of these were known prior to MACHO. The results are consistent with Mira pulsation in the fundamental mode. A sequence comprising 26% of the red variable population can not be explained by pulsation. They propose a dust {kappa}-mechanism in the circumstellar environment is responsible for the long period variation of these objects. The luminosity function of the variables shows a sharp edge at the tip of the red giant branch (TRGB). This is the first clear indication of a population of variable stars within the immediate vicinity of the TRGB. The results indicate this population amounts to 8% of the RGB population near the TRGB.

• Research Organization: Lawrence Livermore National Lab., CA (US)
• Sponsoring Organization: US Department of Energy (US)
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 15003141
• Report Number(s): UCRL-JC-151332
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
DUSTS
LUMINOSITY
MAGELLANIC CLOUDS
PULSATIONS
VARIABLE STARS