论文标题
测量2色有限密度QCD中的强子质量
Measurement of hadron masses in 2-color finite density QCD
论文作者
论文摘要
我们使用$ n_ {f} = 2 $在低温和有限密度下的晶格仿真中研究了2色QCD的强子光谱，其中不仅存在HADRONIC相，而且还出现超氟化相。我们首先计算锥形和Rho Meson光谱，这是从以前的工作中众所周知的。这些介子的光谱顺序围绕夸克化学电位$μ= m^{0}_π/2 $（$ m^{0}_π$：$μ= 0 $）的pion质量，在那里发生了辐射阶段和超级氟化物阶段之间的相变。对于$μ\ gtrsim m^{0}_π/2 $，Pion的有效质量线性增加，而Rho Meson单调的质量则单调减少。此外，我们用isospin $ i = 0 $和角动量$ j^{p} = 0^{\ pm} $测量强子光谱。相同量子数的介子，diquark和反quark的有效质量刚好低于$μ= m^{0}_π/2 $，而三个哈子在超氟阶段中具有相同的质量。它表明，由于$ u（1）_ {b} $对称性破裂，混合发生在与介子与介子和巴属的光谱之间发生。该现象可以用大约$ su（4）$ pauli-gursey对称性的线性Sigma模型来解释。
We investigate hadron spectra in 2-color QCD using lattice simulation with $N_{f}=2$ at low temperature and finite density in which there appears not only the hadronic phase but also the superfluid phase. We first calculate the pion and rho meson spectrum, which is well-known from previous works. The spectral ordering of these mesons flips around the quark chemical potential $μ=m^{0}_π/2$ ($m^{0}_π$: the pion mass at $μ=0$), where the phase transition between the hadronic and superfluid phases occurs. For $μ\gtrsim m^{0}_π/2$, the effective mass for the pion linearly increases while the one for the rho meson monotonically decreases. Furthermore, we measure hadron spectra with the isospin $I=0$ and the angular momentum $J^{P}=0^{\pm}$. The effective masses for the meson, diquark, and antidiquark with the same quantum number become degenerate just below $μ= m^{0}_π/2$, and the three hadrons have the same mass in the superfluid phase. It suggests that mixing occurs between spectra associating with mesons and baryons due to the $U(1)_{B}$ symmetry breaking. This phenomenon can be explained in the linear sigma model with the approximate $SU(4)$ Pauli-Gursey symmetry.
