Abstract: The bremsstrahlung induced Auger lines of kinetic energy of 1500～2500 eV were recordedby X-ray photo-electron spectroscopy.The principal photo-electron lines as well as the P andMo Auger lines of the heteropolyacids (HPA) were observed by bremsstrahlung radiation inone experiment at a same anode and with conventional Al-target.Although the intensitiesof the bremsstrahlung induced Auger lines are rather low, the signal to background ratiofor Mo L₃M₄₅M₄₅ line is similar to that for Mo 3p_1/2 in photoelectron spectra owingto the low values of the background at high energy rigion.From KL₂₃L₂₃ Auger transitionof oxygen in HPA, the minimum energy for double electron removal can be obtained accor-ding to E₁₁ (min) = E_B(k)-E_i (L₂₃⁺L₂₃⁺).

Key words: phosphorus-molybdemum heteropolyacid, double ionization energy of oxy gen, bremsstrahlung-induced Auger transition, X-ray photoelectron spectroscopy