Model Dependence of the Pion Form Factor Extracted from Pion Electro-production

Understand

In 2008 the Jefferson Laboratory $F_\pi$ Collaboration released results for the pion electromagnetic form factor, which they extracted from pion electro-production data.

• The measured values for the pion form factor are model dependent, and require the use of the Vanderhaeghen, Guidal and Laget Regge Model for their extraction.
• While agreement between this model and data is impressive, the theoretical implementation of gauge invariance is less satisfying.
• We would like to establish how well the extracted form factor corresponds to the true form factor.