XRISM Observations of Black Holes

The X-ray Imaging and Spectroscopy Mission (XRISM) is a joint effort of Japan, the United States, and Europe, through JAXA, NASA, and ESA.  Launched in late 2023, the prime instrument aboard XRISM is the "Resolve" X-ray microcalorimeter spectrometer, a revolutionary technology that was developed over 40 years.  Resolve delivers X-ray spectra that are 10 times sharper than any prior instrument, and 10 times more sensitive. This combination is required to leverage spectroscopy to explore environments that cannot be imaged in any wavelength.  Resolve spectra of massive black holes in the centers of active galaxies reveal the full accretion inflow geometry, from the event horizon to the distant molecular torus - a factor of 10⁶ in radius.  The same spectra also reveal a complex web of powerful, accretion-driven winds.  Reaching speeds of 0.2-0.3c, these winds carry enough mass and kinetic energy to remove cold gas from the centers of their host galaxies, demonstrating that feedback from black holes prevents ongoing star formation in galactic centers.  Many of the same features are observed in Resolve spectra of stellar-mass black holes.  The high flux of these small but proximal sources delivers even more detailed information on the structure of accretion disks and relativistic jets.  The XRISM mission is just starting its second annual cycle of observations; over the next many years, the discoveries made with XRISM will lay the groundwork for future studies of black holes in the distant universe with Athena.