Properties and Nature of Be Stars. 16. Closer to a Solution of the Puzzle of 5 κ Dra?

High-dispersion spectrograms of 5 Dra from four observatories during 1972-1988 have been obtained to investigate the medium-term variations and to tackle the controversial problem of the rapid velocity variations. These high-quality data are analyzed, and archival data are reexamined using modern period-search techniques. The controversial period of 0.890384 days is reconfirmed in older data, but is not clear in more recent observations. Periods between about 0.3 and 1.1 days are detected in velocity, line-widths, and line-asymmetry measurement at different epochs. It is shown that these and other short periods reported in the literature are all aliases and/or harmonics of the 0.890-day period. It is suggested that a single physical periodicity may be responsible for the rapid variations seen in 5 Dra.