Search for the nuclear Schiff moment in liquid xenon

A parameter of the $P,T$-odd Hamiltonian characterizing interaction of the nuclear Schiff moment with the gradient of electronic density on the Xe nucleus is calculated for an isolated Xe atom and for liquid xenon. We use a more realistic model of liquid medium than the spherical cell model used by Ravaine and Derevianko [Phys. Rev. A 69, 050101(R) (2004)]. Qualitatively different results for enhancement of the $P,T$-odd effect in liquid xenon are obtained when polarization of the medium is taken into account. Thus, proper choice of the liquid phase model is crucially important even for calculation of the properties dependent mostly on the electronic density near a nucleus.

Figure 1

(Color online) Series I lattice cell geometry and electric field. In the first geometry electric field $E_0$ is directed along the $z$ axis. In the second geometry electric filed $E_{45}$ is directed under 45° to $z$ axis.

Figure 2

(Color online) Series II lattice cell geometry and electric field.

Figure 3

(Color online) Series I $X$ value as a function of the lattice cell size. $X_{\mathrm{SCF}}$ curve corresponds to AGREP-SCF result, $X_{\mathrm{RCCSD}}$ stands for GRECP-RCCSD results. Vertical lines are the functions $R_l=7.5$ and $R_l=8.0$, see Sec. 2.

Figure 4

(Color online) Series I and II AGREP-SCF $X$ values as a function of the cell size. Vertical lines are the functions $R_l=7.5$ and $R_l=8.0$, see Sec. 2.

Figure 5

(Color online) Simulation of the influence of electric filed through lattice geometry. Only atoms on the $z$ axis are plotted. Red color designates the nuclei of the central Xe atom (its shells explicitly treated in the calculations are not shown here), outer shells of the neighboring atoms are half-transparent blue, inner shells and nuclei are blue. On picture $\mathbf{A}$ atoms are without electric field, when center of charge of the outer electronic density coincides with that of the inner shells and nuclei. On picture $\mathbf{B}$ in the electric field (designated $E$) the centers of charge of the outer shells are shifted in respect to the inner part. On picture $\mathbf{C}$ outer shells electronic density of the neighboring atoms is shifted so as to superpose their charge center to those of neighboring atoms but keep the relative position to the central Xe atom the same as in case $\mathbf{B}$.

Figure 6

(Color online) AGREP-SCF $X$ value as a function of the shift of the central atom.