we propose iso observations to derive the near-infrared energy distribution of high-mass x-ray binaries (hmxbs) in order to study the velocity and density structure of the disrupted stellar wind. infrared free-free and free-bound emission is formed in the inner wind regions where the major part of the acceleration takes place. this radiation is modelled rather straightforwardly and is relatively independent of parameters such as the level of ionization and the temperature of the wind that are difficult to determine. x-ray, uv and optical observations have suggested that the stellar wind leaving the massive companion is highly distorted in the direction of the x-ray source. an extended stromgren zone surrounds the x-ray source and trails the compact star in its orbit. inside this zone the radiative acceleration drops leading to the formation of a large and dense shock front in the wind. in general, the stellar wind is expected to be inhomogeneous, which might explain the observed x-ray variability, and focussed towards the x-ray source. infrared observations at different orbital phases will enable us to determine the detailed wind structure and the deviations with respect to undisturbed stellar winds. these observations will provide better insight in the hydrodynamics of radiation-driven winds in this extreme regime and the nature of the interactive accretion proces. the predicted ir flux of these systems is just below the sensitivity limit of iras, but easily feasible with iso. the large extinction in the direction of these systems makes the infrared wavelength domain uniquely suited to study their stellar-wind structure. we will apply for coordinated observations with x-ray, uv and optical telescopes. the scientific goals of this proposal can be reached with iso observations only.
Instrument
CAM01 , PHT03
Temporal Coverage
1997-03-21T11:05:08Z/1997-07-20T02:59:56Z
Version
1.0
Mission Description
The Infrared Space Observatory (ISO) was the world's first true orbiting infrared observatory. Equipped with four highly-sophisticated and versatile scientific instruments, it was launched by Ariane in November 1995 and provided astronomers world-wide with a facility of unprecedented sensitivity and capabilities for a detailed exploration of the Universe at infrared wavelengths.
European Space Agency, 1999, Stellar-Wind Structure In High-Mass X-Ray Binaries Comma Part 2, 1.0, European Space Agency, https://doi.org/10.5270/esa-rvz50zh
