red graph: ${\displaystyle {\frac {N(\alpha )}{N_{0}}}=\underbrace {2.3\cdot {\frac {1}{1.5{\sqrt {2\pi }}}}e^{-0.5\left({\frac {x+1}{1.5}}\right)^{2}}} _{left\ slit}+\underbrace {2.3\cdot {\frac {1}{1.5{\sqrt {2\pi }}}}e^{-0.5\left({\frac {x-1}{1.5}}\right)^{2}}} _{right\ slit}}$

Code: 2.3*1/(1.5*sqrt(2*pi))*exp(-0.5*((x+1)/1.5)^2)+2.3*1/(1.5*sqrt(2*pi))*exp(-0.5*((x-1)/1.5)^2)