# Rutherford scattering using MatLab

Tags:
1. Apr 10, 2014

### ShayanJ

I'm writing a program for simulating the angle distribution of scattered particles from a gold nucleus but I doubt the results. I don't know...But it would be very good if someone check it and give some hints.
I also want to ask should I vary both initial speed and impact parameter in one program or I should write two different programs?
In this program I only vary the initial speed.
Here's the code:
Code (Text):
clear
clc

m=4*1.67*10^(-27);
e=1.6*10^(-19);
q=2*e;
Q=79*e;
k=8.9875518*(10^9);

dt=.01;
t=[0:dt:20];
n=length(t);

da=5;
alpha=[0:da:360];
m=length(alpha);

flags=zeros(m);

y(1)=1;
x(1)=-100;
vy(1)=0;

for v0=0:100

vx(1)=v0;

for i=2:n-1

x(i)=x(i-1)+vx(i-1)*dt;
y(i)=y(i-1)+vy(i-1)*dt;

rcs=(x(i-1)^2+y(i-1)^2)^(3/2);

vx(i)=vx(i-1)+((k*q*Q*x(i-1))/(m*rcs))*dt;
vy(i)=vy(i-1)+((k*q*Q*y(i-1))/(m*rcs))*dt;

end

temp=atan(y(n-1)/x(n-1));

if(temp<0)

temp=temp+2*Pi;

end

theta=temp;

for j=1:m

if (theta==alpha(j) | (theta>(alpha(j)-da) & theta<(alpha(j)+da)))

flags(j)=flags(j)+1;

end

end

end

plot(flags,'o')
hold on
grid on
Any idea is welcome
Thanks

2. May 4, 2014

### Greg Bernhardt

I'm sorry you are not finding help at the moment. Is there any additional information you can share with us?