Photoelectric Observations of UX Ursae Majoris, 1955-1962.

Abstract

Photoelectric observations obtained between 1955 and 1962 show that, while the period of UX UMa was probably increasing in the interval from 1949 to 1953, it has been decreasing since 1953. Photometric solutions of a number of the eclipse-curves have been attempted, for both different wavelengths and different dates. No geometrical solutions exist, presumably owing to distortions of the eclipse-curve by luminous, detached material within the system. Consequently, the photometric elements of this system are completely unknown The variation of eclipse depth with wavelength has been derived. This variation could result either from radiation by a late-type companion star or from the detached material in the system; spectroscopic observations in infrared light during primary minimum are needed to determine which of these possibilities is correct.