Spectral fits to M87 core data from radio to hard x-ray are generated via a specially selected software suite , comprised of the HARM GRMHD accretion disk model and a 2D Monte Carlo radiation transport code .
By determining appropriate parameter changes necessary to fit x-ray quiescent and flaring behavior of M87 ’ s core , we assess the reasonableness of various flaring mechanisms .
This shows that an accretion disk model of M87 ’ s core out to 28 GM / { c ^ { 2 } } can describe the inner emissions .
High spin rates show GRMHD-driven polar outflow generation , without citing an external jet model .
Our results favor accretion rate changes as the dominant mechanism of x-ray flux and index changes , with variations in density of approximately 20 % necessary to scale between the average x-ray spectrum and flaring or quiescent spectra .
The best fit parameters are black hole spin a/M > 0.8 and maximum accretion flow density n \leq 3 \times 10 ^ { 7 } cm ^ { -3 } , equivalent to horizon accretion rates between \dot { m } = \dot { M } / \dot { M } _ { Edd } \approx 2 \times 10 ^ { -6 } and 1 \times 10 ^ { -5 } ( with \dot { M } _ { Edd } defined assuming a radiative efficiency \eta = 0.1 ) .
These results demonstrate that the immediate surroundings of M87 ’ s core are appropriate to explain observed x-ray variability .