Non(anti)commutative N=2 Supersymmetric Gauge Theory from Superstrings   in the Graviphoton Background
  We study open string amplitudes with the D3-branes in type IIB superstring theory compactified on C^2/Z_2. We introduce constant graviphoton background along the branes and calculate disk amplitudes using the NSR formalism. We take the zero slope limit and investigate the effective Lagrangian on the D3-branes deformed by the graviphoton background. We find that the deformed Lagrangian agrees with that of N=2 supersymmetric U(N) gauge theory defined in non(anti)commutative N=1 superspace by choosing appropriate graviphoton background. It is also shown that abelian gauge theory defined in N=2 harmonic superspace with specific non-singlet deformation is consistent with the deformed theory. 
Katsushi Ito, Shin Sasaki