Pion quasiparticle in the low-temperature phase of QCD
Pion quasiparticle in the low-temperature phase of QCD
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DOI：
10.1051/epjconf/201817507045
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发表时间：
2015-06
影响因子：
5
通讯作者：
B. Brandt;A. Francis;H. Meyer;Daniel Robaina
中科院分区：
文献类型：
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作者：
B. Brandt;A. Francis;H. Meyer;Daniel Robaina
在手征有效理论的支持下，我们研究了晶格上双味QCD低温相中的准粒子的性质。我们发现，与随温度升高的静态屏蔽质量相比，介子准粒子质量在真空中显著减小。通过一个简单的论证，在手征极限附近，两个质量有望决定准粒子色散关系。分析了非零动量下轴向电荷密度的两点函数，发现在低动量下，预测的色散关系和介子极点的余量与晶格数据是一致的。这一检验基于对相关函数的拟合，并通过使用Backus-Gilbert方法的第二次分析证实了这一点。
We investigate the properties of the pion quasiparticle in the low-temperature phase of two-flavor QCD on the lattice with support from chiral effective theory. We find that the pion quasiparticle mass is significantly reduced compared to its value in the vacuum, in contrast with the static screening mass, which increases with temperature. By a simple argument, near the chiral limit the two masses are expected to determine the quasiparticle dispersion relation. Analyzing two-point functions of the axial charge density at nonvanishing spatial momentum, we find that the predicted dispersion relation and the residue of the pion pole are consistent with the lattice data at low momentum. This test, based on fits to the correlation functions, is confirmed by a second analysis using the Backus-Gilbert method.