R-parity violating contribution to the neutron electric dipole moment at one-loop order

We present the full result for the down squark mass-squared matrix in the c omplete theory of supersymmetry without R parity where all kinds of R-parit y violating: terms are admitted without bias using an optimal parametrizati on. The major result is a new contribution to LR squark mixing, involving b oth bilinear and trilinear R-parity violating couplings. Among other things , the latter leads to neutron electric dipole moment at one-loop level. Sim ilar mechanisms lead to electron electric dipole moment at the same level. We present here a short report on major features of neutron electric dipole moment from supersymmetry without R parity and give the interesting constr aints obtained.