Title: Weak quadrupole moments,
Abstract: Collective effects in deformed atomic nuclei present possible avenues of
study on the non-spherical distribution of neutrons and the violation of the
local Lorentz invariance. We introduce the weak quadrupole moment of nuclei,
related to the quadrupole distribution of the weak charge in the nucleus. The
weak quadrupole moment produces tensor weak interaction between the nucleus and
electrons and can be observed in atomic and molecular experiments measuring
parity nonconservation. The dominating contribution to the weak quadrupole is
given by the quadrupole moment of the neutron distribution, therefore,
corresponding experiments should allow one to measure the neutron quadrupoles.
Using the deformed oscillator model and the Schmidt model we calculate the
quadrupole distributions of neutrons, $Q_{n}$, the weak quadrupole moments
,$Q_{W}^{(2)}$, and the Lorentz Innvariance violating energy shifts in
$^{9}$Be, $^{21}$Ne , $^{27}$Al, $^{131}$Xe, $^{133}$Cs, $^{151}$Eu,
$^{153}$Eu, $^{163}$Dy, $^{167}$Er, $^{173}$Yb, $^{177}$Hf, $^{179}$Hf,
$^{181}$Ta, $^{201}$Hg and $^{229}$Th.