X-ray and radio variability of Cygnus X-1

摘要: Gleissner, Thomas X-ray and Radio Variability of Cygnus X-1 Stellar black holes neutron stars, so-called compact objects, are the final stages in evolution massive stars with more than ∼ 8 solar masses. If mass a object is greater theoretical limit star, existence hole logical consequence within framework general relativity theory. an binary which consists O-type supergiant accreting from its companion. One characteristic such systems powerful emission temporally spectrally variable radiation. Basically, system can be found either two states, referred to as hard state soft state. Although counted among best studied binaries, exact geometry not clear, just for similar sources. A definite constituent all models accretion disk releasing X-rays. Less agreement exists regard where X-rays originate during Most assume regions photons energized by inverse Compton scattering In recent years, several binaries have been detected possess matter outflows, jets. Apart open questions concerning their formation, contribution jets regime remains clarified. The subject this thesis radio band. analyzed data span years were taken Xray monitoring satellite RXTE simultaneous observations Ryle Telescope at Cambridge (UK). After introductory description basic issues chapter 1, following 2 summarizes mathematics describe variability Fourier analysis well underlying physical mechanisms. phenomenological approaches like shot noise model, recently discovered linear relationship between rms flux lightcurves, rms-flux relation, outlined. 3 relation investigated using lightcurves X-1. It shown that valid on time scales > 5 s, both non-zero intercept C axis argues lightcurve components, example, one non-variable component, or possible constant component. slope k mirrors fractional variability. these hypothesized components described fundamental dependence