5 centimeter OH masers as diagnostics of physical conditions in star-forming regions

We demonstrate that the observed characteristics of the 5 cm OH masers in s tar-forming regions can be explained with the same model and the same param eters as the 18 cm and the 6 cm OH masers. In our already published study o f the 18 cm and the 6 cm OH masers in star-forming regions we had examined the pumping of the 5 cm masers but did not report the results we had found because of some missing collision rate coefficients, which in principle cou ld be important. The recently published observations on the 5 cm masers of OH encourage us to report our old calculations along with some new ones tha t we have performed. These calculations, in agreement with the observations , reveal the main lines at 5 cm as strong masers, the 6049 MHz satellite li ne as a weak maser, and the 6017 MHz satellite line as never inverted for r easonable values of the parameters.