No CrossRef data available.
Published online by Cambridge University Press: 14 August 2015
Through systematic surveys (Johansson et al., Caswell and Haynes, Bowers, Baud, Caswell et al.) some 200 OH masers have been detected that are presumably associated with long period variables of very late spectral type (>M5). Tentatively these stars will be called “OH/IR stars”. They are characterized by their strong emission in the 1612 MHz line which shows a double peak due to the expansion of the shell surrounding these stars. The velocity difference ΔV between the peaks is generally between 10 and 50 km s−1.