Tell-Tale Spectral Signatures from Black Hole Accretion-Disk Winds with XRISM/Resolve
Keigo Fukumura (James Madison University, Harrisonburg)
Tuesday 17/10/2023 @ 14:00, Sala Antonio Sollima IV piano + remoto
Despite an intensive observational effort over the past decades for X-ray disk-winds across different black hole (BH) mass scales (i.e. AGNs and XRBs), our understanding of physics of BH disk-winds (e.g. location, geometry and driving mechanisms) remains limited. In this talk we argue that it is plausible to realistically differentiate the leading launching processes (thermal, radiation and magnetic) with high S/N data from microcalorimeter spectroscopy. In the context of magnetohydrodynamic (MHD) wind scenario, we show that MHD-driving is likely to imprint a tell-tale signature "on average" -- an extended blue tail of unique asymmetry in absorption line profiles. Such a characteristic spectral feature, being almost generic to MHD disk winds due to the intrinsic wind kinematics and density structure, can be utilized as a diagnostic proxy. This tangible "magnetic sign" is also immune to the contamination due to other spectral components such as non-magnetic absorbers and reflection features. We demonstrate a high fidelity of microcalorimeter observations in anticipation of the upcoming XRISM/Resolve data by performing spectral simulations. This diagnostic assessment can in principle provide a long-awaited "smoking gun" to ultimately help answer to the outstanding questions.