On the Spin content of the Nucleon

نویسنده

  • N. F. Nasrallah
چکیده

A QCD sum rule calculation of Balistky and Ji on the spin content of the nucleon is done with a different approach to the evaluation of the bilocal contributions and to the extraction of the nucleon pole residues. The result obtained is much more numerically stable which puts their conclusion that about half of the nucleon spin is carried by gluons on firmer ground. The question of the spin distribution of the nucleon among its constituents has recently received much attention and it is now realized that a substantial fraction of the nucleon spin is carried by the quark orbital and gluon angular momenta [1] 1 2 = 1 2 ∆Σ ( μ )

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تاریخ انتشار 1999