CENTRE DE MATHEMATIQUES APPLIQUEES 
         C.M.A.P.  

Potentiels retardes pour les equations de Maxwell avec condition d'impedence generalisee
T.AbboudT;S.Sayah


We are interested by the scattering of a  transient electromagnetic wave
by a bounded obstacle characterized by a generalized impedance condition.
We consider Engquist-N\'ed\'elec condition approximating thin dielectric
layer, and the classical condition for thin dielectric layers with large
indices. We prove that the retarded potential equation is well posed :
coerciveness, existence and uniqueness properties. For each impedance
condition, numerical validation are shown. We finally compare the two
conditions.

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