National Repository of Grey Literature 3 records found  Search took 0.02 seconds. 
Physics of X-ray binaries
Čechura, Jan
Title: Physics of X-ray binaries Author: Jan Čechura Department: Astronomical Institute of the Academy of Sciences of the Czech Republic Supervisor: doc. RNDr. Petr Hadrava, DrSc. Abstract: We present a novel observation interpreting method for the high-mass X-ray binaries (HMXBs) based on a combination of spectroscopic data and numerical results of a radiation hydrodynamic model of stellar wind in HMXBs. By using an indirect imaging method of Doppler tomography, we calculate synthetic tomograms of a predicted emission in Low/Hard and High/Soft X-ray states and compare them with tomograms produced using phase-resolved optical spectra of Cygnus X-1, a prototype of HMXBs. The emis- sions of HMXBs are determined by the local conditions within the circumstellar medium - namely by local density, temperature, and ionization parameter. These quantities are computed by the radiation hydrodynamic code and strongly depend on the X-ray state of such systems. By increasing intensity of an X-ray emission produced by the compact companion in the HMXB-model, we achieved a complete redistribution of the circumstel- lar medium in the vicinity of the modelled system. These changes (which simulate the transitions between two major spectral states) are also apparent in the synthetic Doppler tomograms which are in a good...
Physics of X-ray binaries
Čechura, Jan ; Hadrava, Petr (advisor) ; Heyrovský, David (referee) ; Krtička, Jiří (referee)
Title: Physics of X-ray binaries Author: Jan Čechura Department: Astronomical Institute of the Academy of Sciences of the Czech Republic Supervisor: doc. RNDr. Petr Hadrava, DrSc. Abstract: We present a novel observation interpreting method for the high-mass X-ray binaries (HMXBs) based on a combination of spectroscopic data and numerical results of a radiation hydrodynamic model of stellar wind in HMXBs. By using an indirect imaging method of Doppler tomography, we calculate synthetic tomograms of a predicted emission in Low/Hard and High/Soft X-ray states and compare them with tomograms produced using phase-resolved optical spectra of Cygnus X-1, a prototype of HMXBs. The emis- sions of HMXBs are determined by the local conditions within the circumstellar medium - namely by local density, temperature, and ionization parameter. These quantities are computed by the radiation hydrodynamic code and strongly depend on the X-ray state of such systems. By increasing intensity of an X-ray emission produced by the compact companion in the HMXB-model, we achieved a complete redistribution of the circumstel- lar medium in the vicinity of the modelled system. These changes (which simulate the transitions between two major spectral states) are also apparent in the synthetic Doppler tomograms which are in a good...
Physics of X-ray binaries
Čechura, Jan
Title: Physics of X-ray binaries Author: Jan Čechura Department: Astronomical Institute of the Academy of Sciences of the Czech Republic Supervisor: doc. RNDr. Petr Hadrava, DrSc. Abstract: We present a novel observation interpreting method for the high-mass X-ray binaries (HMXBs) based on a combination of spectroscopic data and numerical results of a radiation hydrodynamic model of stellar wind in HMXBs. By using an indirect imaging method of Doppler tomography, we calculate synthetic tomograms of a predicted emission in Low/Hard and High/Soft X-ray states and compare them with tomograms produced using phase-resolved optical spectra of Cygnus X-1, a prototype of HMXBs. The emis- sions of HMXBs are determined by the local conditions within the circumstellar medium - namely by local density, temperature, and ionization parameter. These quantities are computed by the radiation hydrodynamic code and strongly depend on the X-ray state of such systems. By increasing intensity of an X-ray emission produced by the compact companion in the HMXB-model, we achieved a complete redistribution of the circumstel- lar medium in the vicinity of the modelled system. These changes (which simulate the transitions between two major spectral states) are also apparent in the synthetic Doppler tomograms which are in a good...

Interested in being notified about new results for this query?
Subscribe to the RSS feed.