An analysis of the hadron structure in covariant chiral effective theory

doi:10.3969/j.issn.1000-5641.2018.03.013

Abstract

Abstract: The matrix elements of twist-2 operators related to nucleon-parton distributions were calculated at one-loop level in the framework of covariant chiral perturbation theory. It was found that all who violate chiral power counting reside in the local terms depending on nucleon mass; hence, they could be readily removed through local counterterms, namely the contributions left over fulfill chiral power counting just like with HBChPT (Heavy Baryon Chiral Perturbation Theory). Meanwhile, one may arrive at incorrect behaviors near baryon thresholds due to the oversimplification of baryon propagators in HBChPT. The results here further support the proposition that the approach of covariant chiral perturbation theory with proper subtractions could both preserve the correct threshold behaviors and fulfill chiral power counting, and hence is a framework more suitable for investigating hadron physics.

Key words: chiral effective field theory, hadron structures, covariant framework, local terms, heavy baryon chiral perturbation theory

CLC Number:

O413.3

WEN Li-hong, YANG Ji-feng. An analysis of the hadron structure in covariant chiral effective theory[J]. Journal of East China Normal University(Natural Sc, 2018, 2018(3): 121-128.

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