Flares in Sgr A* from GRMHD simulations

Sgr A∗ exhibits flares at various wavelengths, but their origin
remains unclear. Magnetic flux rope eruption from the black hole is
one of the possible candidates for explaining the observed Sgr A*
flares. Based on new 3D GRMHD simulations of magnetized accretion
flows, we investigate the dynamics of magnetic flux ropes ejected from
the vicinity of the black hole. We found that the formation of
magnetic flux ropes strongly depends on the size of the magnetic
loops. We also calculate the emissions from the magnetic flux ropes.
From the non-thermal emission models, we can reproduce the observation
of near-infrared flares and time delay. In this talk, I will discuss
the possible origin of the Sgr A* flare.