Pion Electromagnetic Form Factor at Spacelike Momenta
Pion Electromagnetic Form Factor at Spacelike Momenta
A novel method is employed to compute the pion electromagnetic form factor, Fπ(Q2), on the entire domain of spacelike momentum transfer using the Dyson-Schwinger equation (DSE) framework in QCD. The DSE architecture unifies this prediction with that of the pion’s valence-quark parton distribution am...
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Personal Name(s): | Chang, Lei |
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Cloët, I. C. / Roberts, C. D. / Schmidt, S. M. / Tandy, P. C. | |
Contributing Institute: |
Theorie der Starken Wechselwirkung; IAS-4 Wissenschaftlicher Geschäftsbereich I; VS-I Theorie der starken Wechselwirkung; IKP-3 |
Published in: | Physical review letters, 111 (2013) 14, S. 141802 |
Imprint: |
College Park, Md.
APS
2013
|
DOI: |
10.1103/PhysRevLett.111.141802 |
Document Type: |
Journal Article |
Research Program: |
Computational Science and Mathematical Methods Hadron Structure and Dynamics (HSD) |
Link: |
OpenAccess OpenAccess |
Publikationsportal JuSER |
Please use the identifier: http://hdl.handle.net/2128/9207 in citations.
A novel method is employed to compute the pion electromagnetic form factor, Fπ(Q2), on the entire domain of spacelike momentum transfer using the Dyson-Schwinger equation (DSE) framework in QCD. The DSE architecture unifies this prediction with that of the pion’s valence-quark parton distribution amplitude (PDA). Using this PDA, the leading-order, leading-twist perturbative QCD result for Q2Fπ(Q2) underestimates the full computation by just 15% on Q2≳8 GeV2, in stark contrast to the result obtained using the asymptotic PDA. The analysis shows that hard contributions to the pion form factor dominate for Q2≳8 GeV2, but, even so, the magnitude of Q2Fπ(Q2) reflects the scale of dynamical chiral symmetry breaking, a pivotal emergent phenomenon in the standard model. |