OPTICAL SPECTROPHOTOMETRY OF OSCILLATIONS AND FLICKERING IN AE-AQUARII

We observed rapid variations in the nova-like cataclysmic variable AE Aquarii for 1.7 hr with 4.3 s time resolution using the 30 channel (3227-10494 angstrom) spectrophotometer on the Hale 5 m telescope. The 16.5 and 33.0 s oscillations show a featureless blue spectrum that can be represented by f(nu) is-proportional-to nu-0.9, or a blackbody with temperature T approximately 12-57 x 10(3) K and area A approximately 0.2-3 x 10(18) cm2 (d/100 pc)2, much smaller than the accretion disk. Models consisting of the sum of a K star spectrum and a hydrogen slab in LTE at T approximately 6-10 x 10(3) K can fit the spectrum of AE Aquarii reasonably well. The spectrum of a flare indicates optically thin gas with T approximately 8-12 x 10(3) K. The energy released by the flare is large compared to typical stellar flares.