Composite vertices that lead to soft form factors

Abstract

The momentum-space cut-off parameter $\Lambda$ of hadronic vertex functions is studied in this paper. We use a composite model where we can measure the contributions of intermediate particle propagations to $\Lambda$. We show that in many cases a composite vertex function has a much smaller cut-off than its constituent vertices, particularly when light constituents such as pions are present in the intermediate state. This suggests that composite meson-baryon-baryon vertex functions are rather soft, i.e., they have Λconsiderably less than 1 GeV. We discuss the origin of this softening of form factors as well as the implications of our findings on the modeling of nuclear reactions.

REVTex, 19 pages, 5 figs(to be provided on request)

References in corpus (2)

• Role of Vector Mesons in High-Q^2 Lepton-Nucleon Scattering
• Pionic Content of Rho-N-N and Rho-N-Delta Vertex Functions

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