CCD photometry of BM Orionis and other trapezium stars


New light curves have been obtained for the eclipsing binary BM Orionis in the uvbyRI filter regions. The observations were made from 1988 to 1990 using the CCD photometer of the Behlen Observatory of the University of Nebraska. Reduction of all image data to magnitudes for BM Orionis and for each of the five other brightest stars in the Θ1 Orionis group known as the Trapezium was accomplished by use of Stetson's DAOPHOT crowded-field photometry program. Differential magnitudes and light curves for BM Orionis and V1016 Orionis have been constructed using star D of the group as the primary comparison star. Possible indications of variability have also been looked for in the member stars C, E, and F with negative results for stars C and F and positive results for star E. The same CCD frames also contained the stars Θ2 Orionis A and B. A light curve of the possibly-eclipsing spectroscopic binary Θ2 Orionis A folded on its spectroscopic period does show some variability, but no obvious eclipses. © 1994 Kluwer Academic Publishers.


Physics, Astronomy, and Materials Science

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Experimental Astronomy