| Affiliation: | (1) Dyer Observatory, Vanderbilt University, Nashville, Tennessee, USA;(2) Barksdale Observatory, Winter Park, Florida, USA;(3) Cuneo Observatory, Torino, Italy;(4) Specola Solare Ticinese, Locarno-Monti, Switzerland;(5) National Solar Observatory, Tucson, Arizona, USA;(6) Pace University Observatory, Pleasantville, New York, USA;(7) Grup D'Estudis Astronomics, Barcelona, Spain;(8) Kakuda Joshi Observatory, Kakuda, Miyaga, Japan;(9) North Valley Stream Observatory, North Valley Stream, New York, USA;(10) Tamashima Observatory, Kurashiki, Okayama, Japan;(11) Grand Observatory, Pittsburgh, Pennsylvania, USA;(12) East Tennessee State University Observatory, Johnson City, Tennessee, USA;(13) Einstein Astrophysical Observatory, Sidney, Ohio, USA;(14) Sunset Hills Observatory, Hacienda Heights, California, USA |
| Abstract: | DifferentialUBV(RI)KC andUBVRI photometry of the RS CVn binary EI Eridani obtained during December 1987 and January 1988 at fourteen different observatories is presented. A combined visual bandpass light curve, corrected for systematic errors of different observatories, utilizes the photometric period of 1.945 days to produce useful results. Analysis shows the visual light curve to have twin maxima, separated by about 0.4 phase, and a full amplitude of approximately 0.06 mag for the period of observation, a smaller amplitude than reported in the past. The decrease in amplitude may be due to a decrease or homogenization of spot coverage. To fit the asymmetrical light curve, a starspot model would have to employ at least two spotted regions separated in longitude. |
