6533b825fe1ef96bd1281e41
RESEARCH PRODUCT
DISK REFLECTION SIGNATURES IN THE SPECTRUM OF THE BRIGHT Z-SOURCE GX 340+0
T. Di SalvoGiorgio MattR. IariaN. R. RobbaAntonino D'aisubject
PhysicsAstrofisica Alte EnergieAstrophysics::High Energy Astrophysical PhenomenaAstrophysics (astro-ph)Astrofisica Alte Energie;FOS: Physical sciencesAstronomy and AstrophysicsAstrophysics::Cosmology and Extragalactic AstrophysicsRadiusAstrophysicsHorizontal branchAstrophysicsGravitationNeutron starSettore FIS/05 - Astronomia E AstrofisicaSpace and Planetary ScienceIonizationEmissivityK-alphaAstrophysics::Earth and Planetary AstrophysicsEmission spectrumAstrophysics::Galaxy Astrophysicsdescription
We present the preliminary results of a 50 ks long XMM-Newton observation of the bright Z-source GX 340+0. In this Letter we focus on the study of a broad asymmetric emission line in the Fe K alpha energy band, whose shape is clearly resolved and compatible with a relativistically smeared profile arising from reflection on a hot accretion disk extending close to the central accreting neutron star. By combining temporal and spectral analysis, we are able to follow the evolution of the source along its Horizontal Branch. However, despite a significant change in the continuum emission and luminosity, the line profile does not show any strong correlated variation. This broad line is produced by recombination of highly ionized iron (Fe XXV) at an inferred inner radius close to 13 gravitational radii while the fit requires a high value for the outer disk radius. The inclination of the source is extremely well constrained at 35 deg, while the emissivity index is -2.50.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2008-12-10 | The Astrophysical Journal |