The Ultraviolet Flux Variations of ρ Puppis as Recorded by IUE

Abstract

Abstract The archival IUE spectra of the bright δ Scuti star ρ Puppis (HD 67523) reveal large flux variations from 2000 to 3000 Å over an 8 hr observing run. The time separating two successive flux maxima at 2900 Å is 3 hr and 19 minutes which compares well to the period of the radial fundamental mode. At 2900 Å, the flux at maximum is about 1.20 larger than at minimum which is consistent with a 260 K increase of the effective temperature between minimum and maximum. The optical brightness around 5400 Å as recorded by the Fine Error Sensor varied in phase with the ultraviolet flux, corresponding to a decrease in magnitude of −0.11 mag.