A. Blotz et E. Shuryak, INSTANTON-INDUCED CHARM CONTRIBUTION TO POLARIZED DEEP-INELASTIC SCATTERING, Physics letters. Section B, 439(3-4), 1998, pp. 415-420
Recent data on B decays involving eta' may be explained if the singlet
axial current of charmed quarks has a large matrix element to eta', a
nd instantons were shown to be able to generate this effect. We study
the magnitude of charm contributions to nucleon polarized structure fu
nctions generated in a similar way. Comparing the charm contribution,
which is related to a dim(6) gluonic operator, to that of light quarks
, which are related by the anomaly equation to G (G) over tilde, we fo
und that Delta c/Delta Sigma similar or equal to -0.03. Future experim
ents like COMPASS at CERN identifying charm production in DIS can meas
ure this ''intrinsic polarized charm'' component of the nucleon. (C) 1
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