SIMBAD references

Her X-1 was observed with good coverage and good sensitivity over a wide range of 35 day phase with the Ginga LAC in 1988 and 1989. Although several small sections have been previously studied, the spectra from this full set of observations have not been analyzed previously. Main high, short high, and low state spectra all require a two component continuum (absorbed and unabsorbed). Dips and eclipses were identified and the behavior of spectral parameters outside these events is studied. Excluding dips/eclipses, the iron line energy is ≃6.60 keV (whereas during dips/eclipses, it drops to ≃6.4 keV); the column density of the absorbed component is N_H≃10^24.0cm^–2; and the power-law index is α≃0.95. The iron line intensity is well correlated with the total continuum intensity, indicating that reprocessing is important at all times and that a major source of the iron line is the accretion column during main high. The iron line equivalent width (EW) varies between main high, short high, and low states, with mean values for each state of 0.48 keV, 0.66 keV, and ≃1.37 keV, respectively. The ratio of absorbed continuum to unabsorbed continuum, R, also varies with 35 day phase, and EW is correlated with R. The behaviors of absorbed and unabsorbed continuum normalizations, EW and R are consistent with the accretion-column inner-disk model of Scott, Leahy, & Wilson.