2005/01/27 by J. H. He, Jinhua He
Physics and Astronomy · #Astrophysics and Star Formation Studies #Galaxies: Formation, Evolution, Phenomena #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1016/j.newast.2004.11.001
published as New Astron. 10 (2005) 283 · 17 pages, 4 figures, 4 tables
openalex publication_date 2005/01/27 · arxiv created 2005/02/21 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/29
(Pseudo) radiative pumprate of OH 1612 MHz masers is defined for a sample of 44 OH/IR sources (infrared sources with OH 1612 MHz maser), irrespective of the real maser pumping mechanisms. The correlation between the (pseudo) maser pumprates and the evolutionary status of the maser sources reveals that the radiative pumprates of stellar OH masers are nearly fixed, which agrees with the theoretical prediction for radiatively pumped OH maser. The (pseudo) radiative pumprates of interstellar OH masers are not only very small but also varying broadly over two orders of magnitude, which is argued to be the manifestation of varying number of quiet absorbing OH cloudlets and/or various OH maser pumping mechanisms and/or competitive gain between mainline and 1612 MHz OH masers and/or anisotropy of the maser emission. The radiative pumprates of post-AGB OH masers very possibly decrease with increasing IRAS C32 color indices and distribute in an interim region between the stellar and interstellar OH masers in the pumprate-color diagram.