  The K-shell emission line of neutral irons from the Galactic center (GC)
region is one of the key for the structure and activity of the GC. The origin
is still open question, but possibly due either to X-ray radiation or to
electron bombarding to neutral atoms. To address this issue, we analyzed the
Suzaku X-ray spectrum from the GC region of intense neutral iron line emission,
and report on the discovery of Kalpha lines of neutral argon, calcium, chrome,
and manganese atoms. The equivalent widths of these Kalpha lines indicate that
the metal abundances in the GC region should be ~1.6 and ~4 of solar value,
depending on the X-ray and the electron origins, respectively. On the other
hand, the metal abundances in the hot plasma in the GC region are found to be
~1-2 solar. These results favor that the origin of the neutral Kalpha lines are
due to X-ray irradiation.
