The Proton Electromagnetic Form Factor Ratio at Low Q2

Ron Guy
Tel Aviv


Electromagnetic form factors of the nucleon are model-independent observables which encode our ignorance 
of its complex internal structure. In  recent years significant attention has been drawn to these observables 
due to  the discovery of unexplained deviations from previously measured results. 

Recoil polarization measurements are allowing the electric to magnetic  form factor ratios be determined 
with unprecedented precision. New results  from MIT-BLAST and, more recently, from Hall A at Jefferson 
Lab indicate  that there is an unexpected decrease in the proton form factor ratio atlo w Q2 . Even newer 
data is expected to come from MAINZ and JLab  experiments in the near future. 

This talk will discuss the nucleon form factors, specifically in the low Q2 region, previous and new 
measurements, and the potential impacts of these results.