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arXiv · 0709.0369

Sea-quark effects in the pion charge form factor

Q. B. Li·D. O. Riska
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Abstract

It is shown that the data on the pion charge form factor admit the possibility for a substantial sea-quark components in the pion wave function. If the charge form factor is calculated with instant form kinematics in a constituent quark model that is extended to include explicit $(q\bar q)^2$ components in the pion wave function, that component will give the dominant contribution to the calculated $π^+$ charge form factor at large values of momentum transfer. The present experimental values $Q^2$ can be described well with $(q\bar q)^2$ component admixtures of up to 50%. The sensitivity of the calculated $π^+$ charge form factor to whether one of the quarks or one of the antiquarks is taken to be in the P-state is small.

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Q. B. Li, D. O. Riska. 2007-09-04. Sea-quark effects in the pion charge form factor. https://doi.org/10.1103/physrevc.77.045207

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