The electromagnetic pion form factor and instantons
نویسندگان
چکیده
منابع مشابه
The Electromagnetic Pion Form Factor and Instantons
We calculate the electromagnetic pion form factor at intermediate spacelike momentum transfer from the QCD sum rule for the correlation function of two pseudoscalar interpolating fields and the electromagnetic current. This correlator receives essential contributions from direct (i.e. small-scale) instantons, which we evaluate under the assumption of an instanton size distribution consistent wi...
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The Standard Model prediction for the magnetic moment of the muon requires a determination of the electromagnetic form factor of the pion at high precision. It is shown that the recent progress in ππ scattering allows us to obtain an accurate representation of this form factor on the basis of the data on e+e− → π+π−. The same method also applies to the form factor of the weak vector current, wh...
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The electromagnetic pion form factor, Fπ(q 2), is calculated for spacelike-q2 in impulse approximation using a confining quark propagator, S, and a dressed quarkphoton vertex, Γμ, obtained from realistic, nonperturbative Dyson-Schwinger equation studies. Good agreement with the available data is obtained for Fπ(q 2) and other pion observables, including the decay π0 → γ γ. This calculation sugg...
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متن کاملElectromagnetic pion form factor at finite temperature
The electromagnetic form factor of the pion in the space-like region, and at finite temperature, Fπ(Q 2, T ), is obtained from a QCD Finite Energy Sum Rule. The form factor decreases with increasing T, and vanishes at some critical temperature, where the pion radius diverges. This divergence may be interpreted as a signal for quark deconfinement. John Simon Guggenheim Fellow 1994-1995 The possi...
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ژورنال
عنوان ژورنال: Physics Letters B
سال: 1995
ISSN: 0370-2693
DOI: 10.1016/0370-2693(94)01596-5