Cosmic Ray Spallation in Radio-Quiet Active Galactic Nuclei: A Case
  Study of NGC 4051
  We investigate conditions for and consequences of spallation in radio-quiet
Seyfert galaxies. The work is motivated by the recent discovery of significant
line emission at 5.44 keV in Suzaku data from NGC 4051. The energy of the new
line suggests an identification as Cr I Ka emission, however the line is much
stronger than would be expected from material with cosmic abundances, leading
to a suggestion of enhancement owing to nuclear spallation of Fe by low energy
cosmic rays from the active nucleus. We find that the highest abundance
enhancements are likely to take place in gas out of the plane of the accretion
disk and that timescales for spallation could be as short as a few years. The
suggestion of a strong nuclear flux of cosmic rays in a radio-quiet Seyfert
galaxy is of particular interest in light of the recent suggestion from Pierre
Auger Observatory data that ultra-high-energy cosmic rays may originate in such
sources.
