New example of charge conjugation and parity violation from search for a   permanent electric dipole moment of Rubidium atom
  Quantum mechanics thinks that all atoms do not have permanent electric dipole moment (EDM) because of their spherical symmetry. Therefore, there is no polar atom in nature except for polar molecules. The electric susceptibility Xe caused by the orientation of polar substances is inversely proportional to the absolute temperature T while the induced susceptibility of atoms is temperature independent. Using special capacitors our experiments discovered that directional motion of Rb atoms in a non-uniform electric field and ground state Rb atom is polar atom with a large EDM: d(Rb) =2.72*10-29C.m = 1.70*10-8e.cm. The experiment showed that the relationship between Xe of Rb vapor and T is just Xe =B/T, where the slope B =380(k) as polar molecules. Its capacitance C at different voltage V was measured. The C-V curve shows that the saturation polarization of Rb vapor has be observed when E more than 8.5*104V/m. New example of CP (charge conjugation and parity) violation occurred in Rb atoms (see arXiv 0809.4767). If Rb atom has a large EDM, why the linear Stark effect has not been observed? The article discussed the question thoroughly. Our results are easy to be repeated because the details of the experiment are described in the article. 
Pei-Lin You and Xiang-You Huang