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H.H. Lanning (CSC/STScI), R.A. Wade, M. Eracleous (Penn State)
We have obtained low-dispersion spectra for 62 ``Lanning'' stars. These stars show ultraviolet excesses based on photographic plates double--exposed in the U and B passbands. Thirty--five Lanning stars brighter than B = 13 were observed with the GoldCam spectrograph at the KPNO 2.1m telescope, covering 3875--7530 Å\ with a resolution of 4.5 Å. Twenty--seven Lanning stars with B between 13 and 16 were observed with the Marcario Low Resolution Spectrograph (LRS) at the Hobby-Eberly Telescope, covering 4260--7245 Å\ with a resolution of 4.9 Å. The stars were drawn from Papers I, II and (mostly) V by Lanning (1973) and Lanning & Meakes (1994, 2000). One--dimensional spectra were extracted and flux--calibrated. The similar--resolution digital Library of Stellar Spectra (Jacoby, Hunter & Christian 1984) was used as a source of ``standard'' spectra for classification purposes. Both the standard spectra and the Lanning star spectra were approximately flattened, and rough classification was carried out by eye.
The brighter sample includes a number of late F/early G stars (possibly metal--weak) with relatively few high--gravity stars, while the fainter sample shows the reverse. We interpret this as a result of ``deselection'' by interstellar reddening of stars beyond a certain distance in these Milky Way fields. Thus fainter stars in the sample are typically of lower intrinsic luminosity. Several unusual spectra, including composite hot+cool systems, emission line stars, a He--strong star, and the exciting star of an H II region were found and will be discussed. The fraction of Lanning stars that are ``interesting'' in these ways is significant.