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X-ray spectra from cores of galaxy clusters can be strongly distorted by resonant scattering of line photons, affecting metal abundance and gas velocity measurements. We introduce simulated spectral models that take into account the resonant scattering effect, radial variations of thermodynamic properties of the hot gas, projection effects and small-scale isotropic gas motions. The key feature of the models is that all these effects are treated self-consistently for the whole spectrum, rather than for individual lines. The model spectra are publicly available and can be used for direct comparison with observed projected spectra. Comparison with the existing XMM-Newton and Chandra data of the Perseus Cluster shows that even though there is no strong evidence for the resonant scattering in Perseus, the low energy resolution of the X-ray CCDs is not sufficient to robustly distinguish spectral distortions due to the resonant scattering, different metal abundance profiles and different levels of gas turbulence. Future Astro-H data will resolve most of the problems we are facing with CCDs. With the help of our models, the resonant scattering analysis can be done self-consistently using the whole spectral information, constraining the level of gas turbulence already with a 100 ks observation with Astro-H.
Thanks to its high spectral resolution (~5 eV at 6 keV), the Soft X-ray Spectrometer (SXS) on board Hitomi enables us to measure the detailed structure of spatially resolved emission lines from highly ionized ions in galaxy clusters for the first tim
Astro-H will be the first X-ray observatory to employ a high-resolution microcalorimeter, capable of measuring the shift and width of individual spectral lines to the precision necessary for estimating the velocity of the diffuse plasma in galaxy clu
Astro-H will be able for the first time to map gas velocities and detect turbulence in galaxy clusters. One of the best targets for turbulence studies is the Coma cluster, due to its proximity, absence of a cool core, and lack of a central active gal
Extending the earlier measurements reported in Hitomi collaboration (2016, Nature, 535, 117), we examine the atmospheric gas motions within the central 100~kpc of the Perseus cluster using observations obtained with the Hitomi satellite. After correc
This white paper addresses selected new (to X-ray astronomy) physics and data analysis issues that will impact ASTRO-H SWG observations as a result of its high-spectral-resolution X-ray microcalorimeter, the focussing hard X-ray optics and correspond