Particle acceleration in the inner ~ 200 pc of the Galaxy is discussed, where
diffuse TeV gamma-rays have been detected by the High Energy Stereoscopic
System (HESS) observation. The diffuse gamma-ray emission has a strong
correlation with molecular clouds with large velocity dispersion, indicating
the presence of turbulence. It is argued that the turbulence may contribute to
the acceleration of cosmic rays via stochastic acceleration. The stochastic
acceleration may energize cosmic-ray protons up to ~ 100 TeV and electrons to ~
1 TeV in a relatively tenuous medium. The difference in the efficiency between
protons and electrons supports the hadronic scenario of the diffuse TeV
gamma-ray emission.Comment: 4 pages, 1 figure, accepted by PASJ Letter
