  In the triplet equal-spin-pairing states of both 3He-A phase and Sr2RuO4
superconductor, existence of Half-Quantum Vortices HQVs are possible. The
vortices carry half-integer multiples of magnetic quantum flux (hc/2e). To
obtain equilibrium condition for such systems, one has to take into account not
only weak interaction energy but also effects of Landau Fermi liquid. Our
method is based on the explanation of the HQV in terms of a BCS-like wave
function with a spin-dependent boots. We have considered l=2 order effects of
the Landau Fermi liquid. We have shown that the effects of Landau Fermi liquid
interaction with l=2 are negligible. In stable HQV, an effective Zeeman field
exists. In the thermodynamic stability state, the effective Zeeman field
produces a non-zero spin polarization in addition to the polarization of
external magnetic field.
