Matches in SemOpenAlex for { <https://semopenalex.org/work/W3100642648> ?p ?o ?g. }
Showing items 1 to 71 of
71
with 100 items per page.
- W3100642648 abstract "Context. The wind-wind collision in a massive star binary system leads to the generation of high temperature shocks that emit at X-ray wavelengths and, if particle acceleration is effective, may exhibit non-thermal radio emission. Cyg OB2#9 represents one of a small number of massive star binary systems in this class. Aims. X-ray and radio data recently acquired as part of a project to study Cyg OB2#9 are used to constrain physical models of the binary system, providing in-depth knowledge about the wind-wind collision and the thermal, and non-thermal, emission arising from the shocks. Methods. We use a three-dimensional, adaptive mesh refinement simula tion (including wind acceleration, radiative cooling, and the orbital motion of the stars) to model the gas dynamics of the wind-wind collision. The simulation output is used as the basis for radiative transfer calculations considering the thermal X -ray emission and the thermal/non-thermal radio emission. Results. The flow dynamics in the simulation show that wind accelerati on (between the stars) is inhibited at all orbital phases by the opposing star’s radiation field, reducing pre-shock vel ocities below terminal velocities. To obtain good agreement with the X-ray observations, our initial mass-loss rate estimates requir e a down-shift by a factor of∼ 7.7 to 6.5×10 −7 M⊙ yr −1 and 7.5×10 −7 M⊙ yr −1 for the primary and secondary star, respectively. Furthermore, the low gas densities and high shock velocities in Cyg OB2 #9 are suggestive of unequal electron and ion temperatures, and the X-ray analysis indicates that an (immediately post-shock) electron-ion temperature ratio of≃ 0.1 is also required. The radio emission is dominated by (non-thermal) synchrotron emission. A parameter space exploration provides evidence against models assuming equipartition between magnetic and relativistic energy densi ties. However, fits of comparable quality can be attained with models having stark contrasts in the ratio of magnetic-to-relativistic e nergy densities. Both X-ray and radio lightcurves are largely insensitive to viewing angle. The variations in X-ray emission with orbital phase can be traced back to an inverse relation with binary separation and pre-shock velocity. The radio emission also scales with pre-shock velocity and binary separation, but to positive powers (i.e . not inversely). The radio models also reveal a subtle effect whereby inverse Compton cooling leads to an increase in emissivity as a result of the synchrotron characteristic frequency being signifi cantly reduced. Finally, using the results of the radio analysis, we estimat e the surface magnetic field strengths to be ≈ 0.3− 52 G." @default.
- W3100642648 created "2020-11-23" @default.
- W3100642648 creator A5021425926 @default.
- W3100642648 creator A5062100349 @default.
- W3100642648 creator A5085851544 @default.
- W3100642648 date "2014-06-22" @default.
- W3100642648 modified "2023-09-27" @default.
- W3100642648 title "The 2.35 year itch of Cygnus OB2 #9 III. X-ray and radio emission analysis based on three dimensional hydrodynamical modelling" @default.
- W3100642648 cites W1680420368 @default.
- W3100642648 cites W2123226345 @default.
- W3100642648 hasPublicationYear "2014" @default.
- W3100642648 type Work @default.
- W3100642648 sameAs 3100642648 @default.
- W3100642648 citedByCount "1" @default.
- W3100642648 countsByYear W31006426482016 @default.
- W3100642648 crossrefType "journal-article" @default.
- W3100642648 hasAuthorship W3100642648A5021425926 @default.
- W3100642648 hasAuthorship W3100642648A5062100349 @default.
- W3100642648 hasAuthorship W3100642648A5085851544 @default.
- W3100642648 hasBestOaLocation W31006426481 @default.
- W3100642648 hasConcept C121332964 @default.
- W3100642648 hasConcept C150846664 @default.
- W3100642648 hasConcept C151730666 @default.
- W3100642648 hasConcept C153294291 @default.
- W3100642648 hasConcept C169233029 @default.
- W3100642648 hasConcept C204530211 @default.
- W3100642648 hasConcept C2779343474 @default.
- W3100642648 hasConcept C44870925 @default.
- W3100642648 hasConcept C62520636 @default.
- W3100642648 hasConcept C74902906 @default.
- W3100642648 hasConcept C86803240 @default.
- W3100642648 hasConceptScore W3100642648C121332964 @default.
- W3100642648 hasConceptScore W3100642648C150846664 @default.
- W3100642648 hasConceptScore W3100642648C151730666 @default.
- W3100642648 hasConceptScore W3100642648C153294291 @default.
- W3100642648 hasConceptScore W3100642648C169233029 @default.
- W3100642648 hasConceptScore W3100642648C204530211 @default.
- W3100642648 hasConceptScore W3100642648C2779343474 @default.
- W3100642648 hasConceptScore W3100642648C44870925 @default.
- W3100642648 hasConceptScore W3100642648C62520636 @default.
- W3100642648 hasConceptScore W3100642648C74902906 @default.
- W3100642648 hasConceptScore W3100642648C86803240 @default.
- W3100642648 hasLocation W31006426481 @default.
- W3100642648 hasLocation W31006426482 @default.
- W3100642648 hasLocation W31006426483 @default.
- W3100642648 hasOpenAccess W3100642648 @default.
- W3100642648 hasPrimaryLocation W31006426481 @default.
- W3100642648 hasRelatedWork W1582595102 @default.
- W3100642648 hasRelatedWork W1851683996 @default.
- W3100642648 hasRelatedWork W1978948427 @default.
- W3100642648 hasRelatedWork W2019748881 @default.
- W3100642648 hasRelatedWork W2023472668 @default.
- W3100642648 hasRelatedWork W2038412805 @default.
- W3100642648 hasRelatedWork W2043360680 @default.
- W3100642648 hasRelatedWork W2044362806 @default.
- W3100642648 hasRelatedWork W2067886648 @default.
- W3100642648 hasRelatedWork W2100873801 @default.
- W3100642648 hasRelatedWork W2101846043 @default.
- W3100642648 hasRelatedWork W2157559054 @default.
- W3100642648 hasRelatedWork W2162545417 @default.
- W3100642648 hasRelatedWork W2166400669 @default.
- W3100642648 hasRelatedWork W3098388292 @default.
- W3100642648 hasRelatedWork W3099077544 @default.
- W3100642648 hasRelatedWork W3099841565 @default.
- W3100642648 hasRelatedWork W3100330009 @default.
- W3100642648 hasRelatedWork W3103584267 @default.
- W3100642648 hasRelatedWork W3123657528 @default.
- W3100642648 isParatext "false" @default.
- W3100642648 isRetracted "false" @default.
- W3100642648 magId "3100642648" @default.
- W3100642648 workType "article" @default.