The Fermi-LAT has revealed that rotation powered millisecond pulsars (MSPs)
are a major contributor to the Galactic γ-ray source population. We
discuss the γ-ray emission process within the context of the outer gap
accelerator model, and use a Monte-Calro method to simulate the Galactic
population of the γ-ray emitting MSPs. We find that the outer gap
accelerator controlled by the magnetic pair-creation process is preferable in
explaining the possible correlation between the γ-ray luminosity and the
spin down power. Our Monte-Calro simulation implies that most of the
γ-ray emitting MSPs are radio quiet in the present sensitivity of the
radio survey, indicating that most of the γ-ray MSPs have been
unidentified. We argue that the Galactic Fermi unidentified sources located
at high latitudes should be dominated by MSPs, whereas the sources in the
galactic plane are dominated by radio-quiet canonical pulsars.Comment: 2011 Fermi Symposium proceedings - eConf C11050