298 citations · 554 across the 9 of their papers we have counts for
Showing astro-phShow all
2 papers · 1 filter
astro-ph2001★ 21 cited
The Cross-Spectra of Cir X-1: Evolution of Time Lags
J. L. Qu, W. Yu, T. P. Li
Earlier work showed that the track in the X-ray hardness-intensity diagram of Cir X-1 corresponds to a Z track in its color-color diagram. In this paper, we study the cross spectru…
astro-ph1997★ 93 cited
Spectral State Transitions in Aql X-1: Evidence for `Propeller' Effects
S. N. Zhang, W. Yu, W. Zhang
Aql X-1 is a soft X-ray transient source and emits type I X-ray bursts. A spectral state transition was observed with RXTE during its outburst decay in February and March 1997. Its…