Detection of new stellar sources of vibrationally excited silicon monoxide maser emission at 6.95 millimeters.
We have searched 32 selected sources for V = 1, J = 1 0 SiO maser emission at 43,122.0 MHz ( 6.93 mm), and detected 16 of them. Two of them, Ori A and W Hya, had been detected previously by Thaddeus et al. We detected eight of the SiO V = 1, J = 2 1 SiO maser sources observed by Kaifu, Buhl, and Snyder at 86,243.27 MHz ( 3.48 mm), and found that the V = 1, J = 1 0 maser is often the most intense transition, and hence promises to be the best frequency to use in searching for new maser sources. Most of the detected maser sources reported in this paper can readily be associated with known late-type stars; therefore we have been able to analyze the velocity patterns and stellar classification implications found from our data. The proposed maser mechanisms are discussed in the context of current observations. Subject headings: late-type stars - masers - molecules, interstellar