We observed the v = 1, J = 2 → 1, 86 GHz SiO maser transition from Mira ( Ceti) near stellar pulsation phase = 0.3 with the Coordinated Millimeter VLBI Array. Maser emission was detected on two of the baselines, and general size and brightness parameters were extracted. For this epoch (1998.26), we find that the maser features extend over roughly 1.5 to 2 stellar radii R* in the north-south direction. The limited image fidelity was insufficient to assess whether a ringlike morphology typical of other evolved stars with SiO masers appears in Mira also. The brightness temperatures (≤1010.5 K) and spot sizes (≥0001) generally resemble those of other maser sources measured by VLBI at 86 GHz, such as VX Sgr and R Cas. We find no coherent velocity structure suggested by the 86 GHz SiO masers toward Mira.
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