Adelman & Brunhouse (1998) used 79 uvby observations from the FCAPT and the V values of Winzer (1974) to find a period of 1.06457 days which was similar to that of Winzer. As they found small apparent differences between light curves obtained in the 1995-96, the 1996-97, and the 1997-98 observing seasons, HR 1297 was observed again during the 1998-99 observing season at which time 117 good uvby observations were obtained to better define the light curves. When the Scargle periodogram was used with the new data for u, there were two significant peaks one corresponding to the previously determined period and one to its alias near 15.723 days. In the new data set sometimes two or more values were obtained on the same night. As these pairs of values showed small differences and as Catanzaro et al. (1999) indicated a v sin i value of 29 km s-1, the longer period was preferred. To bring the V data of Winzer (1974) into phase agreement with FCAPT y values, the following ephemeris was found
HJD( ) 2441247.475 0.005 (15.7490 0.0002) .
With this period, the FCAPT values from different observing seasons appear to
form the same light curve contrary to the previous observations (Fig. 3).
As for year 9 a 2.5 mag neutral density filter was removed, to bring the u, v, b, and y 1999 values into agreement with previous
FCAPT values -2.435, -2.452, -2.380, and -2.403 mag, respectively, were added.
The light curves are in phase with suggestions that the primary minimum
consists of two minima in some light curves. For u, there is one near
phase 0.30 and the other near phase 0.6. The minima for v and b
are less flat bottomed that for u and more asymmetric. For y the
minimum is again flat bottomed but it is smaller in phase extent than for u. The amplitudes for u, v, b, and y are, 0.045,
0.035, 0.035, and 0.035 mag, respectively. The differences in the shapes of
these light curves suggests a photosphere with somewhat variable properties.
|Figure 3: Differential FCAPT uvby photometry of HR 1297 plotted with the ephemeris HJD( ) = 2441247.475 + 15.7490 E. The FCAPT values of this paper are shown as open squares and those of Adelman & Brunhouse (1998) as solid circles. In the y graph, the V values of Winzer (1974) plotted with the y zero point of Adelman & Brunhouse are shown as + signs|
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