四费米子算符对复合粒子质量的影响
Effect of four-fermion operators on the mass of the composite particles
摘要：
我们提出了一个理论框架，用于评估四费米子算符对封闭强耦合规范理论中复合粒子质量的影响。禁闭部门是由一个非本地的Nambu-Jona Lasinio行动，而四个费米子运营商，从不同的部门，是本地的。为了说明这种方法，我们研究了一个简单的玩具模型与全球$SU(2)_L\times SU(2)_R\to SU(2)_V$对称性破缺，和一个四费米子运营商打破$SU(2)_L\times SU(2)_R$，但保持$SU(2)_V$。在粒子谱中，我们只包括赝标同位旋三重态，即与手征对称性破缺有关的赝Nambu-Goldstone玻色子和最轻的标量单重态。在检验了非定域模型成功地解释了双味QCD中的实验结果后，我们研究了作为四费米子耦合函数的质量谱。对于我们具体选择的四费米子算符，我们发现，随着四费米子耦合的增长，赝标三重态的质量增长，而最轻的标量单重态的质量几乎不受影响。我们认为，这些结果可以直接测试的晶格，并简要讨论了这种技术的动态电弱对称性破缺模型的可能应用。
英文摘要：
We propose a theoretical framework for evaluating the effect of four-fermion operators on the mass of composite particles in confining strongly-coupled gauge theories. The confining sector is modelled by a non-local Nambu-Jona Lasinio action, whereas the four-fermion operators, arising from a different sector, are local. In order to illustrate the method, we investigate a simple toy model with a global $SU(2)_L\times SU(2)_R\to SU(2)_V$ symmetry breaking, and a four-fermion operator breaking $SU(2)_L\times SU(2)_R$ but preserving $SU(2)_V$. In the particle spectrum we only include the pseudoscalar isospin triplet, that is the pseudo-Nambu-Goldstone bosons associated with chiral symmetry breaking, and the lightest scalar singlet. After checking that the nonlocal model successfully accounts for the experimental results in two-flavour QCD, we investigate the mass spectrum as a function of the four-fermion coupling. For our specific choice of four-fermion operator, we find that the mass of the pseudoscalar triplet grows, whereas the mass of the lightest scalar singlet is approximately unaffected, as the four-fermion coupling grows. We argue that these results can be directly tested on the lattice, and briefly discuss possible applications of this technique to models of dynamical electroweak symmetry breaking.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
