Chiral Symmetry in light-front QCD

• Main Authors: Meng-Hsiu Wu, 吳孟修
• Other Authors: Wei-Min Zhang
• Format: Others
• Language: en_US
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/07167039669348464423

博士 === 國立成功大學 === 物理學系碩博士班 === 93 === 　The definition of chiral transformations in light-front field theory is very different from the conventional form in equal-time formalism. We begin from studying the consistency of chiral transformations in free fermion theory. And then we extend to studying the chiral symmetry in light-front QCD. Meanwhile, we derive a complete new light-front axial-vector current for light-front field theory. Physically, the breaking of chiral symmetry in light-front QCD is only associated with helicity flip interaction between quarks and gluons. Remarkably, the new axial-vector current does contain some physical implications. We study in two aspects, the spontaneous chiral symmetry breaking in light-front formulation and the feature of hadronic transition matrix element in which the new light-front axial-vector current does not contain the pion pole part so that the associated chiral charge smoothly describes pion transitions for various hadronic processes.