[en] In order to improve the impurity control and to increase the interaction of ions with neutral gas in FEB-E divertor, the dynamic gas target divertor is designed by means of combination of gas puffing and impurity injection. The detached plasma is in a high confinement performance H mode associated with both a large fraction of edge radiation power (50%-80%) and a large drop in plasma pressure along the SOL open field line (about 90%). The plasma pressure drop factor on the divertor f_p is estimated with the two-point SOL transport model and the impurity radiation model. The simulation results show that the plasma pressure drop factor is not only related to the radiation fraction, but also depends greatly on the stagnation point density