COMPOSITE VERTICES THAT LEAD TO SOFT FORM-FACTORS

The momentum-space cutoff 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 cutoff 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 Λ considerably less than 1 GeV. We discuss the geometrical origin of this softening of form factors as well as the implications of our findings on the modeling of nuclear reactions. © 1995 The American Physical Society.