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H.J. Augensen (Widener U.), W.D. Heintz (Swarthmore College), V. Bonina, J. Dunlap, S. Jonas, D. Olszewski, J. Gottwald, D. Pringle, M.R. Schultz (Widener U.)
We report on the results of an extensive program of photometric monitoring of northern and near-southern declination objects taken from the New Catalogue of Stars Suspected of Variability of Light (Kukarkin et al. 1982) and also from the recent New Catalogue of Stars Suspected of Variability of Light, Supplement Version 1.0 (Kazarovets et al. 1998). Observations have been made through R and/or V filters using an Apogee AP-6 CCD camera mounted on the 24-inch refractor at the Sproul Observatory. Over 4000 individual observations of approximately 250 stars have been obtained since the Sproul program began in 1998, and new objects are continually being added. Supplemental observations have been procured using the 31-inch reflecting telescope of the National Undergraduate Research Observatory located in Flagstaff, Arizona. We find that approximately 20% of the stars in our program exhibit distinct variability with amplitudes greater than about 0.2 magnitude, while about 40% show no variations at all. Most of the remaining 40% have too few observations to make a definitive categorization at this time, but we expect that perhaps one-fourth of these undecided stars will ultimately prove to be variable. While the majority of the confirmed variables exhibit slow, large-amplitude variations, about sixteen of these objects apparently vary more rapidly, on a time scale of a few days or less. A small number of the slow variables such as NSV 13514 exhibit season-to-season changes in their behavior. Results for several of the more interesting, well-observed objects, including NSV 549, 1447, 11241, 12866, 13826, 14159, and 14365, will be discussed in some detail.
This work has been supported by a Faculty Development Grant from Widener University and a Provost Grant from Swarthmore College. The authors also gratefully acknowledge the use of the Lowell Observatory 31-inch telescope which, under agreement with Northern Arizona University and the NURO consortium, is operated 60% of the time as the National Undergraduate Research Observatory.
The author(s) of this abstract have provided an email address for comments about the abstract: wheintz1@swarthmore.edu