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We present the first variability study of the 1720 MHz OH masers located inthe Galactic Center. Most of these masers are associated with the interactionbetween the supernova remnant SgrAEast and the interstellar medium, but a fewmasers are associated with the Circumnuclear Disk. The monitoring programcovered five epochs and a timescale of 20-195 days, during which no masersdisappeared and no new masers appeared. All masers have previously beendetected in a single epoch observation about one year prior to the start of themonitoring experiment, implying relatively stable conditions for the 1720 MHzOH masers. No extreme variability was detected. The masers associated with thenortheastern interaction region between the supernova remnant and the +50km/smolecular cloud show the highest level of variability. This can be explainedwith the +50km/s molecular cloud being located behind the supernova remnant andwith a region of high OH absorbing column density along the line of sight.Possibly the supernova remnant provides additional turbulence to the gas inthis region, through which the maser emission must travel. The masers in thesouthern interaction region are located on the outermost edge of SgrAEast whichline of sight is not covered by either absorbing OH gas or a supernova remnant,in agreement with the much lower variability level observed. Similarly, themasers associated with the CND show little variability, consistent with themarising through collisions between relatively large clumps of gas in the CNDand no significant amount of turbulent gas along the line of sight.

Very Large Array monitoring of 1720 MHz OH masers toward the Galactic Center