ω0=.;
Manipulate[
Plot[(g^2)((4(ω^2)+(g^2))/((((((ω0)^2)-(ω^2)))^2)+(g^2)(ω^2)))/.ω0->50,{ω,0,100},PlotRange->{0,5},PlotStyle->Thick,AxesLabel->{"ω","I(ω) = A(ω)^2+B(ω)^2"},Ticks->{{{50, "(Subscript[ω, 0])"}},None},PlotLabel->"Spektrum tlumeně kmitajícího atomu"],
{{g,5,"tlumení Γ = (1/τ)"},1,10},ControlPlacement->Top]

Plot[(g^2)((4(ω^2)+(g^2))/((((((ω0)^2)-(ω^2)))^2)+(g^2)(ω^2)))/.{ω0->50,g->{1,7,17,30,39}},{ω,0,100},PlotRange->{0,5}]

Plot[(g^2)((4(ω^2)+(g^2))/((((((ω0)^2)-(ω^2)))^2)+(g^2)(ω^2)))/.{ω0->50,g->{1,2,3,4,5}},{ω,40,60},PlotRange->{0,5}]