We have searched for time variability of the stars in the central parsec of the Galaxy through K-band (2.2 μm) imaging and photometry. The observations were made with an array-based camera at the NASA Infrared Telescope Facility in 1991, 1992, and 1993. In 1991, on timescales ranging from 20 s to a week, no time variability greater than 0.1 mag was found for about five dozen sources in this region, and the brighter sources were stable to ~0.05 mag. On timescales of 1-2 yr, we found a new source near IRS 10E that varied in brightness by at least 1 mag and detected variability of 0.15 to 0.5 mag in several other sources, most notably the red giants IRS 9 and IRS 12N. None of the luminous blue stars identified in the Galactic center region shows evidence for variability.
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