A discussion of how to determine if E0 parameters found in a fit are sensible and how excessively large E0 values can affect data analysis
Relevant references
Alain Michalowicz and Gilberto Vlaic, J. Synchr. Rad. (1998), 5, 1317-1320
S.D. Kelly and B. Ravel, American Institute of Physics Conference Proceedings, 882, p. 135 (2007)