HD-81410 - A NEW RS-CVN BINARY

B and V photometry of HD 81410 obtained on 34 nights during 1981 January 3-March 14 is presented. The amplitudes are found to be ~ 0.15 mag both in B and V. It is found that a 12.86833 day period satisfies all the available photometric data. Orbital elements of the system have been derived from the published radial velocity measurements. The orbital period, strong Ca II H and K emission and the spectral types of the components indicate that HD 81410 is a member of the RS CVn group. It is seen that the star becomes redder at fainter visual magnitudes. We attribute this to the relatively cooler temperatures of the 'darker regions' present on the visible hemisphere. © 1982 Royal Astronomical Society. Provided by the NASA Astrophysics Data System.