Towards a High Resolution View of the Accretion Disk Wind in PDS 456

Twenty years of X-ray observations of the prototype accretion disk wind in the nearby QSO, PDS 456, are presented. The observations with XMM-Newton, NuSTAR and Suzaku covered 17 independent epochs from 2001-2019. Physically self consistent radiative transfer disk wind models are used, providing a measurement of the energetics at each epoch. The wind is persistent across all epochs, varying in velocity between 0.25-0.35c and with a kinetic power of 10-50% of Eddington. The wind terminal speed and kinetic power are found to become faster (more energetic) with luminosity, suggesting that the radiation field may help to regulate the wind power. Disk wind simulations of PDS 456 with XRISM are shown, providing a glimpse of what may soon be observed through calorimeter resolution observations. XRISM will accurately resolve the Fe K wind profile, revealing both the disk wind acceleration mechanisms and the velocity structure along the wind.