New limits on the violation of the strong equivalence principle in strong field regimes.

The Strong Equivalence Principle (SEP) demands, besides the validity of the Einstein Equivalence Principle, that all self-gravitating bodies feel the same acceleration in an ex- ternal gravitational eld. It has been found that metric theories of gravity other that than general relativity typically predict a violation of the SEP. In case of the Earth-Moon system (weak eld system) this violation is called the Nordtvedt effect. It has been shown by Damour and Schthat small- eccentricity long-orbital-period binary pulsars with a white dwarf companion provide excellent conditions to test the SEP in strong eld regimes. Based on newly discovered binary pulsars this paper inves- tigates a possible violation of the SEP in strong eld regimes. New limits with an improved condence level are presented. The results of this paper lead to constrains on the combi- nation "= 2+ of the only two (post) 2 -Newtonian parameters " and that arise from the (post) 2 -Newtonian approximation of