16 meson A , as well as the baryonic and anti-baryonic “axial-vector” bosons, A$_{B}$$_{+}$ and A$_{B}$$_{−}$ (see Table III), the A will mix with baryonic and anti-baryonic “vector” bosons, V$_{B}$$_{+}$ and V$_{B}$$_{−}$ , and A$_{B}$$_{+}$ and A$_{B}$$_{−}$ will mix with ω meson for µ$_{B}$ > M$_{π}$ . The effect of mixing among A , V$_{B}$$_{+}$ and V$_{B}$$_{−}$ will make m$_{V}$$_{B}$$_{+}$ lighter since m$_{V}$$_{B}$$_{+}$ is the smallest among three at µ$_{B}$ = M$_{π}$ . As a result, the m$_{V}$$_{B}$$_{+}$ becomes more stable than that shown in FIG. 4, and the lattice data will be reproduced. This strongly suggests that there is a large mixing among A , V$_{B}$$_{+}$ and V$_{B}$$_{−}$ for heavy π s such as the one adopted in the lattice analysis [7]. This indicates that the mass of isovector meson with J P = 1 + shown in FIG. 2 of Ref. [7] is nothing but m$_{V}$$_{B}$$_{+}$ observed through the large mixing. On the other hand, the mixing among A$_{B}$$_{+}$ , A$_{B}$$_{−}$ and ω will generally break the degeneracy between the ρ and ω mesons as shown in e.g. Ref. [8], which does not seem to agree with the lattice result. Then, the mixing expected to small enough to reproduce the lattice result. In this paper, we constructed a low energy effective Lagrangian for the two-color QCD including the “vector” bosons (mesons with J P = 1 − and diquark baryons with J P = 1 $^{+}$) in addition to the pseudo Nambu-Goldstone bosons (mesons with J P = 0 − and baryons with J P = 0 $^{+}$) based on the chiral symmetry breaking pattern of SU (2 N$_{f}$ ) → Sp (2 N$_{f}$ ) in the framework of the hidden local symmetry (HLS). The “vector” bosons were introduced as the gauge bosons of the Sp (2 N$_{f}$ ) HLS. In the HLS formalism, the “vector” bosons and the external chiral gauge bosons are included independently, so that we can naturally incorporate the chemical potential µ$_{B}$ as the vacuum expectation value (VEV) of the external gauge boson for baryon number. We studied the vacuum structure of the model in the case of N$_{f}$ = 2 introducing the effects of current quark masses and the baryon chemical potential into the leading order 5. SUMMARY AND DISCUSSIONS TABLE III: Summary of the “axial-vector” fields Field Generator I B J P A 1 , 2 , 3 X 1 , 2 , 3 1 0 1 + A$_{B}$$_{+}$ = ( A 5 − iA $^{4}$) $_{/}$√$_{2}$ ( X 5 − iX $^{4}$) $_{/}$√$_{2}$ 0 +1 1 − A$_{B}$$_{−}$ = ( A 5 + iA $^{4}$) $_{/}$√$_{2}$ ( X 5 + iX $^{4}$) $_{/}$√$_{2}$ 0 1 1 −