How can i normalize two plots having same R and Z coordinate to be exact or agree

Hello, i have this data as attached that i rename as psi_n, R and Z. I also have an equation as i present in the code named psi_a, both psi_n and psi_a will have same R and Z coordinate. I want to normalize the two figures in one plot and to be exact or to agree but i could not get a good results. below is my code, please help me to check

mu=4*pi*10^-7;
Pm=0.43e12;    
sigma=0.1;
psi0 = 0.49;
R0=1.05;
psit=0.4;
P2=(Pm*sigma)/(1+sigma);
d =(2*mu*P2)/psi0.^2; 
h = 0.02;
lamda = pi/h;
psi_a = ((1./2.*(sqrt(d)).*(R.^2).*(real(exp((i.*(sqrt(d)).*R.^2)./2))))./(1./2.*(sqrt(d)).*(R0.^2).* ...
(real(exp((i.*(sqrt(d)).*R0.^2)./2)))).*cos(lamda.*Z./R0).*psi0*psit)-1./(2.*sigma);
% the normalized figures
figure
range_n = max(psi_n(:)) - min(psi_n(:));
n_psi = (psi_n - min(psi_n(:))) / range_n;
[C,h] = contour(R,Z,n_psi,10,'-.r','linewidth',2);
hold on
range_a = max(psi_a(:)) - min(psi_a(:));
a_psi = (psi_a - min(psi_a(:))) / range_a;
[C,h] = contour(R,Z,a_psi,10,'b','linewidth',2);

[Sargondjani]

Please be precise on what you want, and where the problem in your code is. If you can't normalize multiple variables, then only give us the formulas for the normilization, and what is wrong about the result.