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THE ENERGY OUTPUT FROM AN ACTIVE GALACTIC NUCLEUS IS RELEASED VERY CLOSE TO THE CENTRAL BLACK HOLE AND THEREFORE PROBING THE RELATIVISTIC REGION OF THE INNER ACCRETION FLOW--AT THE INTERSECTION OF INFLOW AND OUTFLOW--IS ESSENTIAL TO UNDERSTANDING HOW SUPERMASSIVE BLACK HOLES EFFECT THEIR GALACTIC ENVIRONMENTS. XARM WILL PROVIDE AN UNPRECEDENTED VIEW OF THIS FEEDBACK PROCESS IN ACCRETING BLACK HOLE SYSTEMS. IN THIS SHORT STATEMENT I POSE THREE OF THE BIGGEST QUESTIONS IN BLACK HOLE ACCRETION AND DESCRIBE FUTURE XARM INVESTIGATIONS THAT WILL WORK TO RESOLVE THEM. WHAT IS THE SPIN OF A BLACK HOLE? THE SPIN OF THE BLACK HOLE STRONGLY AFFECTS THE OVERALL ACCRETION EFFICIENCY AND MAY ALSO BE RESPONSIBLE FOR DRIVING RELATIVISTIC JETS. FURTHERMORE OBTAINING A TRUE DISTRIBUTION OF BLACK HOLE SPIN IN THE LOCAL UNIVERSE WILL CONSTRAIN THE GROWTH HISTORY OF SMBHS WHETHER MOSTLY THROUGH PROLONGED ACCRETION WHERE ANGULAR MOMENTUM BUILDS UP OVER TIME OR THROUGH CHAOTIC ACCRETION (VOLONTERI 2005). TO MEASURE BLACK HOLE SPIN WE REQUIRE SPECTRA OF THE BROAD IRON LINE THAT CAN BE DISTINGUISHED FROM NARROW EMISSION AND ABSORPTION FEATURES PRODUCED THROUGH REPROCESSING IN THE TORUS A WIND OR THE OUTER ACCRETION DISC. RESOLVE WILL PROVIDE A CLEAN VIEW OF BOTH THE BROAD IRON LINE AND SOFT EXCESS WHICH WILL VASTLY IMPROVE OUR UNDERSTANDING OF SYSTEMATIC UNCERTAINTIES ASSOCIATED WITH SPIN MEASUREMENTS. IN ADDITION TO AGN BOTH INSTRUMENTS ON XARM WILL MEASURE THE SPIN IN BLACK HOLE BINARIES WITH RESOLVE MEASURING SPIN THROUGH THE BROAD IRON LINE METHOD AND XTEND MAKING AN INDEPENDENT SPIN MEASURE THROUGH MODELING OF THE THERMAL CONTINUUM. ARE ACCRETION DISC WINDS POWERFUL ENOUGH TO DRIVE FEEDBACK? IN RECENT YEARS FAST OUTFLOWS OF 0.1-0.3C HAVE BEEN FOUND IN AGN AND BHBS THROUGH HIGHLY IONISED ABSORPTION FEATURES IN THE IRON K BAND USING CCD DETECTORS AND IN NARROW SOFT X-RAY LINES USING REFLECTION GRATINGS. THESE WINDS CARRY A LOT OF KINETIC ENERGY WHICH MAY BE ENOUGH TO DRIVE FEEDBACK ON GALACTIC SCALES. RESOLVE WILL MEASURE THE STRUCTURE OF ULTRAFAST OUTFLOWS IN UNPRECEDENTED DETAIL. UFOS ARE LAUNCHED CLOSE TO THE BLACK HOLE AND ARE HIGHLY DYNAMIC (TOMBESI ET AL. 2013). WE NEED HIGHER SPECTRAL RESOLUTION TO MAP OUT THE VELOCITY PROFILE OF THE FE XXV/XXVI OUTFLOWS AND HIGHER COLLECTING AREA THAN PREVIOUS REFLECTION GRATING SPECTROMETERS TO UNDERSTAND THE TIME VARIABILITY OF WINDS. FURTHERMORE CURRENT CCD DETECTORS OFTEN CANNOT DISTINGUISH BETWEEN FE XXV AND FE XXVI THEREFORE CAUSING LARGE UNCERTAINTIES IN THE OUTFLOW VELOCITY AND KINETIC ENERGY. WITH XARM WE WILL DISTINGUISH THESE LINES AND LOOK FOR HIGHER ORDER TRANSITIONS OF FE XXV AND FE XXVI AS WELL AS ABSORPTION FROM LIGHTER ELEMENTS.

$236,938FY2020National Aeronautics and Space AdministrationNASA

Massachusetts Institute Of Technology, Cambridge MA

Investigators

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