title: [The survey and its interpretation for interstellar OH and H2O masers].
abstract: A statistics of sky survey for interstellar H2O and OH masers is presented. These masers can be classified into 3 categories. The total number of sources in each category is of the same order of magnitude, and they can maintain--10(5) years. But there are fewer than half masers with detectable H II regions. An improved radiative pumping mechanism is proposed, and it overcame the known drawback of former radiative models. The observationally statistical results can be interpreted by both the new mechanism and the evolutional model with gravitational force of star responsible for the H II region.
authors.affiliation: Department of Physics, Beijing Normal University, Beijing 100875, China.
authors.forename: Han-peng
authors.initials: HP
authors.lastname: Liu
authors.forename: J R
authors.initials: JR
authors.lastname: Forster
authors.forename: Jin
authors.initials: J
authors.lastname: Sun