SECULAR CHANGES IN THE CLASSICAL CEPHEID Y-OPHIUCHI

We provide new, extensive photoelectric photometry of the classical Ce pheid Y Oph, and use this, together with other new and earlier photoel ectric photometry, to re-examine the question of whether or not this C epheid has shown a secular change in its pulsational amplitude over th e last half-century. We conclude that its amplitude has declined at a rate similar to the average rate of Polaris' amplitude decline. We als o re-examine the period change of Y Oph and find that this has been sm ooth without any sudden jumps or phase offsets during this timespan. ( C) 1995 American Astronomical Society.