Systematic Spectral and Timing Study of Dips in HER X-1
Abstract
We propose a systematic study of the phenomenon of pre-eclipse dips in Her X-1: observe the first 5 dips (using 4 RXTE orbits for each dip) in 2 consecutive Main-High states. The goal is to do correlated spectral and timing analysis with emphasis on the phenomenon of periodic variability in dips which was seen by HEAO-2, EXOSAT, Ginga and now XTE (our analysis). The observed periods range from 2.4 to 108 min. It is assumed that dips are caused by intervening absorbing cold material (NH), wich apparently can vary periodically. Where spectra are measured, NH appears to vary in anticorrelation to the count rate. we like to improve the understanding of the accretion stream/disk interaction and how the dips are formed. We expect a systematic dependence on 35 day phase.
- Publication:
-
RXTE Proposal
- Pub Date:
- 1999
- Bibcode:
- 1999rxte.prop40015S