No CrossRef data available.
Published online by Cambridge University Press: 04 August 2017
The O-C curves — widely used for investigating the period behaviour of variable stars — are generally constructed under the assumption that the period changes are linear in time. If it is indeed so, the main trend of the diagram should outline a positive or negative parabola and β values are determined to characterize the curvature of the parabolae, i.e. the rate of change of the period. This rate, however, even in the case of ω Cen does not indicate exact parabola (Belserene, 1973).