Gaussian pulse normalized plotting

Hi, I am trying to plot a fifth derivative gaussian pulse and then take its subsequent fft. But the problem that I am facing is that the plot of the curve is of extremely high magnitude and centralized across y-axis. But the desired plot need to be normalized along y-axis within [1,-1] and on positive x-axis. Currently the constant C is considered as 1. the code is as follows:

clc clear all t = linspace(-0.5,0.5,1e7).*1e-9; sig = 51*1e-12 ; %v = (-(t.^5)./(sqrt(2*pi)*sig^11) + (10*t.^3)./(sqrt(2*pi)*sig^9) - (15*t)/(sqrt(2*pi)*sig^7)) .* exp((-t.^2)./(2*sig^2)); v = zeros(1,length(t)) ; C = 1; size(t) for i = 1:length(t) v(i) = C*(-((t(i))^5)/(sqrt(2*pi)*sig^11) + (10*(t(i))^3)/(sqrt(2*pi)*sig^9) - (15*t(i))/(sqrt(2*pi)*sig^7)) * exp((-(t(i))^2)/(2*sig^2)); end

length(v) figure; plot(t,v); fs = 1e3; t = -0.5:1/fs:0.5; L = length(t) ; n = 2^nextpow2(L); amp = fft(v,n) ; amp1 = fftshift(amp) ; f = fs*(0:(n/2))/n; %f=fs*(-n/2:n/2-1)/n ; p = abs(v/n) ;

figure; plot(f,20*log10(p(1:n/2+1)))