95GHZ METHANOL MASERS NEAR DR-21 AND DR-21(OH)

We used the BIMA array to map the 95 GHz 80 → 71A+ transition of methanol and the 98 GHz J = 2 → 1 transition of CS toward the DR 21(OH) and DR 21 star-forming regions. Several strong methanol masers were found. The positions of the two brightest masers were measured with an accuracy of about ±0″.3. Toward DR 21(OH), the positions, velocities, and line shapes of the 95 GHz masers are in excellent agreement with those of the 84 GHz 5-1 → 40 E methanol masers previously mapped by Batrla and Menten, demonstrating that maser emission in both transitions originates from the same clumps of gas. The methanol masers are offset from CS emission peaks and from other known infrared and maser sources; they may possibly be clustered along the interface between outflows, traced by shock-excited H2 emission, and dense ambient gas, traced by CS emission.