y=Abs[-(η/(2k))Csc[θ/2]^2*Exp1-(η/(2k))Csc[π/2-θ/2]^2*Exp2+2/k*(Sin[δ0]*P0*Exp[*α0+*δ0]+Sin[δ2]*P2*Exp[*α2+*δ2]+Sin[δ4]*P4*Exp[*α4+*δ4])]^2​​​​
2
Abs-4.14062×
-27
10
1.+6.34963×
-12
10

2
Csc
θ
2

-4.14062×
-27
10
1.+6.34963×
-12
10

2
Sec
θ
2

+2.60841×
-15
10
δ0

Sin[δ0]+
1
2
(0.+1.90489×
-11
10
)+δ2

-1+3
2
Cos[θ]
Sin[δ2]+
1
8
(0.+2.64568×
-11
10
)+δ4

3-30
2
Cos[θ]
+35
4
Cos[θ]
Sin[δ4]