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Composite vertices that lead to soft form factors

L. C. Liu·Q. Haider·J. T. Londergan
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Abstract

The momentum-space cut-off parameter $Λ$ 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 $Λ$. 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.

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L. C. Liu, Q. Haider, J. T. Londergan. 1995-03-09. Composite vertices that lead to soft form factors. https://doi.org/10.1103/physrevc.51.3427

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