Instanton-induced charm contribution to polarized deep-inelastic scattering
نویسندگان
چکیده
Recent data on B decays involving η′ may be explained if the singlet axial current of charmed quarks has a large matrix element to η′, and instantons were shown to be able to generate this effect. We study the magnitude of charm contributions to nucleon polarized structure functions 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 GG̃, we found that ∆c/∆Σ = -(0.2-0.08). Future experiments like COMPASS at CERN identifying charm production in DIS can measure this “intrinsic polarized charm” component of the nucleon.
منابع مشابه
Non-zero Quark Modes Contribution to the QCD-Instanton-Induced Deep Inelastic Scattering
Instanton-induced deep-inelastic processes are considered. Unlike previous results we calculate nonzero quark modes contribution. As was shown [1], QCD-instantons can appear at the intermediate stage of deep inelastic scattering (DIS) and be, in principle, observed at HERA (DESY) [2, 3]. Specifically, instantons can be produced in quark-gluon subprocess (Fig.1).
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