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BATSE Pulsars
Vela X-1

Recent Flux & Frequency History

Eclipses in Vela X-1 are not accounted for in the plot above. This results in 2 days of non-detection every (8.96 day) orbital period, and can affect the plotted flux values in the days adjacent to the eclipse.
Monitor Parameters ASCII File Typical Pulse Profile PS File

CGRO/BATSE Mission Frequency History

Data for the above plot are obtained from an enhanced analysis. Two frequency measurements per system orbit are made, with times of eclipse excluded.
PS file FITS file (FITS readme file)

Long-term Frequency History

The same BATSE data is plotted here, along with measurements of the source made since discovery of pulsations.
PS file