Monitoring Faint Variable Stars at Minimum: A Work in Progress

Volume 27 number 1 (1999)

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Gary P. Emerson

Irene R. Little-Marenin

CASA, CB 389

Abstract

Many of the AAVSO program variable stars have approximate minimum magnitudes listed only as "< __ magnitude." Intrigued by these "unknowns," the authors decided to monitor these stars at minimum light to measure and, in some cases, derive the lower magnitudes for these objects. As this project evolves, these stars are becoming more interesting. Many of the stars are Miras and change color as they fade. Some of the closer (brighter) stars are also sources of maser emission. Assuming a period-luminosity relation for these stars, we find that most are at distances of greater than 2 kpc, and their maser emission is too faint to be detected. Because this project is in its infancy, few results can be reported at this time, but observations and observation techniques are discussed. Other CCD-equipped observatories are encouraged to participate in these valuable observations.