Notes about changes to qfs_new12_sub.f

•  Modified the form factors Ge and Gm for proton and neutron in function sigqfs .  This function  calculates elastic and quasi-elastic cross sections.
• Add the subroutines get_gegm_prot and get_gegm_neut at the end of qfs_new12_sub.f  . These codes return Ge and Gm/u . For get_ge_gm_prot there are two options: "dipole" and "bosted" . "bosted' is a fit by Peter Bosted. Previously the code was using "dipole". For get_gegm_neut the two options are: "dipole" and "walcher". "walcher" is a fit to data by J. Friedrich and Th. Walcher in Eur.Phys.J. A17 (2003) 607-623. "dipole" is the usual dipole shape for proton Ge, Gm and neutron Gm with the neutron Ge treated specially as shown below in example of the old code. To change from one model to another, one has to change the variable model in the subroutines.
  
• Modified section of code in function sigqfs so that one can have Ge and Gm have different values. The following code:

  ---

         formp=1.+qms*up**2/4./pm**2
       formp=formp/(1.+qms/4./pm**2)
       formp=formp+qms*up**2*tan(thr/2.)**2/2./pm**2
       formp=formp*fd(qms,ap)**2
       sigep=signs*formp
       falloff=(1.+5.6*qms/4./pm**2)**2
       formn=(qms*un/4./pm**2)**2/falloff+qms*un**2/4./pm**2
       formn=formn/(1.+qms/4./pm**2)
       formn=formn+qms*un**2*tan(thr/2.)**2/2./pm**2
       formn=formn*fd(qms,ap)**2

• was replaced with:   

  ---

           call get_gegm_prot(qms,ap,gepsq,gmpsq)
      gmpsq=gmpsq*up**2
      formp=gepsq+qms*gmpsq/4./pm**2
      formp=formp/(1.+qms/4./pm**2)
      formp=formp+gmpsq*qms*tan(thr/2.)**2/2./pm**2
      sigep=signs*formp
      call get_gegm_neut(qms,ap,gensq,gmnsq)
      gmnsq=gmnsq*un**2
      formn=gensq+qms*gmnsq/4./pm**2
      formn=formn/(1.+qms/4./pm**2)
      formn=formn+gmnsq*qms*tan(thr/2.)**2/2./pm**2


  ---

• Comparison of the above parametrization to world data is shown in plots of  proton Ge and  Gm and neutron Gm.    Also, in the proton Ge and Gm plots are comparisons to a fit by John Arrington and the parametrization that is in MASCARAD.  At the kinematics of RSS elastic, Ge is not important. For proton Gm, the MASCARAD parametrization is a little high.