The secular evolution of the orbital angular momentum ( OAM ) , the systemic mass ( M = M _ { 1 } + M _ { 2 } ) and the orbital period of 114 chromospherically active binaries ( CABs ) were investigated after determining the kinematical ages of the sub-samples which were set according to OAM bins .
OAMs , systemic masses and orbital periods were shown to be decreasing by the kinematical ages .
The first order decreasing rates of OAM , systemic mass and orbital period have been determined as \dot { J } = 3.48 \times 10 ^ { -10 } ~ { } yr ^ { -1 } per systemic OAM , \dot { M } = 1.30 \times 10 ^ { -10 } ~ { } yr ^ { -1 } per systemic mass and \dot { P } = 3.96 \times 10 ^ { -10 } ~ { } yr ^ { -1 } per orbital period respectively from the kinematical ages .
The ratio of d \log J / d \log M = 2.68 , which were derived from the kinematics of the present sample , implies that there must be a mechanism which amplifies the angular momentum loss \bar { A } = 2.68 times in comparison to isotropic angular momentum loss of hypothetical isotropic wind from the components .
It has been shown that simple isotropic mass loss from the surface of a component or both components would increase the orbital period .