2 00 3 The “ proton spin crisis ” - a quantum query
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چکیده
The “proton spin crisis” was introduced in the late 1980s, when the EMC-experiment revealed that little or nothing of a proton’s spin seemed to be carried by its quarks. The main objective of this paper is to point out that it is wrong to assume that the proton spin, measured by completely different experimental setups, should be the same in all
منابع مشابه
ar X iv : h ep - p h / 02 08 24 2 v 2 1 3 N ov 2 00 2 Nucleon strangeness and spin crisis ?
We summarize three alternative extensions of the quark-valence picture of nucleon strangeness and spin, including (1) gluon spin in QCD, (2) Bjorken sum rule and QCD, (3) D–E meson mixing and tadpole leakage. All three approaches suggest that ∼ 40% of the nucleon’s spin (as well as its momentum) resides with quarks, but that less than 6% is due to strange quarks.
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تاریخ انتشار 2003