Determination of tidal distortion in the eclipsing binary system V621 Cen by means of deviations from the third Kepler law

In this paper we determine the tidal distortion parameter k(m) of the secondary partner (mass loser) of the semi-detached eclipsing binary system V621 Cen by comparing the phenomenologically determined orbital period P-b = 3.683549(11) d to the Keplerian one p(Kep) computed with the values of the relevant system's parameters determined independently of the third Kepler law itself. Our result is k(m) = -1.5 +/- 0.6. Using the periastron precession, as traditionally done with other eclipsing binaries in eccentric orbits, would have not been possible because of the circularity of the V621 Cen path. (c) 2008 Elsevier B.V. All rights reserved.