  We show that the subset of high energy neutrino events detected by IceCube
which correlate with the Galactic center (within uncertainties of their
reconstructed arrival directions) could originate in the collisions of protons
accelerated by the Sagittarius (Sgr) A* disk dynamo. Under very reasonable
assumptions on source parameters we demonstrate that the supermassive black
hole at the center of the Galaxy could launch protons and nuclei with multi PeV
energies. Acceleration of these particles in a period of seconds up to Lorentz
factors of \sim 10^7 is possible by means of the Blandford-Znajek mechanism,
which wires the spinning magnetosphere of Sgr A* as a Faraday unipolar
inductor. During the acceleration process the \sim PeV progenitors of \sim 50
TeV neutrinos radiate curvature photons in the keV energy range. We show that
IceCube neutrino astronomy with photon tagging on the Chandra X-ray Observatory
could provide a valuable probe for the Blandford-Znajek acceleration mechanism.
We also argue that EeV neutrinos, which may be produced in a similar fashion
during the merging of binary black holes, could become the smoking gun for
particle acceleration in a one-shot boost.
