HIGH-SPEED ULTRAVIOLET PHOTOMETRY OF HD-60435

In this Letter, we present the first high-speed ultraviolet photometry of a oscillating Ap star, HD 60435. After removing known orbital effe cts related to the Hubble Space Telescope, we confirm the presence of a strong pulsation period at a frequency of 123.70 cycles per day. In addition, we find significant amplitude modulation of this frequency t hat we suggest could be the result of beating of multiple periodicitie s. In this context, we suggest evidence for the presence of four addit ional frequencies at nu = 120.56, 126.55, 149.49, and 221.03 cycles pe r day. Three of these frequencies correspond well to frequencies detec ted in optical observations of HD 60435. The fourth, at 149.49 cycles per day, if real, is a potentially new pulsation mode that has not bee n detected in ground-based observations of this star. The amplitude of the 123 cycles per day pulsation is significantly larger in the ultra violet than it is in the blue.