Deep inelastic eγ scattering at high Q2

The electromagnetic and weak structure functions of the photon can be studied in the deep inelastic electron-photon processes eγ→e+X and eγ→ν+X. While at low energies only virtual photon exchange is operative in the neutral-current process, additional Z-exchange becomes relevant for high Q2 of order MZ2 at e+e− linear colliders. Likewise the charged-current process can be observed at these high energy colliders. By measuring the electroweak neutral- and charged-current structure functions, the up- and down-type quark content of the photon can be determined separately.