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D.H. Bradstreet, F.D. Jewett, D.P. Steelman (Eastern University), E.F. Guinan, J.C. Tracey, G.P. McCook (Villanova University)
Nova Aquilae 1999-2 (V1494 Aql) reached maximum brightness of V = +3.8 on 03 December 1999, making it one of the brightest novae observed in the northern hemisphere. Photoelectric photometry began at Villanova University on 08/09 December 1999 and continued in March 2000 in Arizona using the 0.8m APT. The APT photometry was done using Strömgren uvby and H alpha narrow/wide filters. This photometry was continued through the end of 2000 when the star became too faint to observe. A visual light curve was constructed from all the available photometry. From the rapid decline in brightness, the system is classified as a "fast" nova. From March-August 2000 oscillations were detected in the light curve up to 0.5 mag in amplitude with a characteristic timescale of several days. The nature of these oscillations is being investigated and will be discussed in the poster. Several long observing runs were undertaken at this time to search for underlying binary eclipse signatures, and although small variations were detected, they were not periodic.
In July 2001 V1494 Aql was reported to exhibit eclipses at approximately V = +14 (IAUC Nos. 7665 & 7674). In August 2001 we resumed monitoring of the star using unfiltered CCD photometry. So far we have obtained 20+ nights of observations, primarily using the 40-cm reflector at Eastern University. This photometry confirms the presence of a deep (0.6 mag) eclipse with a period of 0.1346186 days. Thus V1494 Aql is a cataclysmic variable (CV) in which the eclipse occurs as the cooler companion eclipses the accretion disk surrounding the white dwarf. The light curve varies continuously in brightness even outside of eclipse, as well as exhibiting night-to-night variations in its shape. Although the light curve is variable, it shows persistent features that include a maximum in brightness prior to and immediately following the eclipse, and at times a secondary minimum at ~ 0.5P. We are attempting to model the light curves to determine the properties of the disk and accretion effects (hot spot/gas stream) and will present our results in this poster. In addition we are searching for optical evidence of the 40-min x-ray oscillations recently found from CHANDRA (Starrfield, priv. comm.)
This research is partially supported by NSF/RUI grant AST 00-71260 which we gratefully acknowledge.
The author(s) of this abstract have provided an email address for comments about the abstract: dbradstr@eastern.edu