# How can I fix an error when I try to draw a region function in a contour plot?

I am trying to draw a region function in a contour plot. My function has five variables and I want to reduce the number of variables by assuming some appropriate values for three of the variables.

Here is set up for my code.

αem = 1/137
me = 0.511/1000
mmu = 102.8/1000
F[x_] := (5*x^4 - 14*x^3 + 39*x^2 - 38*x - 18*x^2*Log[x] + 8)/(12*(1 - x)^4)
G[x_] := (x^3 + 3*x - 6*x*Log[x] - 4)/(2*(1 - x)^3)
Γtotalmu = 3*10^-19
M4C = 200
Δamumax = (26.1 + 8.0*2)*10^-10
Δamumin = (26.1 - 8.0*2)*10^-10


And here is my code.

c12L = 1
s14L = π/4

gLμμ[s24L2_, s12L_] := (c12L*Sqrt[s24L2] - Sqrt[1 - s24L2]*s12L*s14L)^2;
gLμe[s24L2_, s12L_] := (s12L*Sqrt[s24L2] +
c12L*Sqrt[1 - s24L2]*s14L)*(s12L*Sqrt[s24L2] -
Sqrt[1 - s24L2]*s12L*s14L);
gLee[s24L2_, s12L_] := (s12L*Sqrt[s24L2] + c12L*Sqrt[1 - s24L2]*s14L)^2;
gLμE[s24L2_, s12L_] := (Sqrt[1 - s14L^2]*
Sqrt[1 - s24L2])*(Sqrt[1 - s12L^2]*Sqrt[s24L2] -
Sqrt[1 - s24L2]*s12L*s14L);
gLeE[s24L2_, s12L_] := (Sqrt[1 - s14L^2]*Sqrt[1 - s24L2])*(s12L*Sqrt[s24L2] +
Sqrt[1 - s12L^2]*Sqrt[1 - s24L2]*s14L);
gLEE[s24L2_, s12L_] := (1 - s14L^2)*(1 - s24L2);

c12R = 1
s14R = 0

gRμμ[s24R2_, s12R_] := (c12R*Sqrt[s24R2] - Sqrt[1 - s24R2]*s12R*s14R)^2;
gRμe[s24R2_, s12R_] := (s12R*Sqrt[s24R2] +
c12R*Sqrt[1 - s24R2]*s14R)*(s12R*Sqrt[s24R2] -
Sqrt[1 - s24R2]*s12R*s14R);
gRee[s24R2_, s12R_] := (s12R*Sqrt[s24R2] + c12R*Sqrt[1 - s24R2]*s14R)^2;
gRμE[s24R2_, s12R_] := (Sqrt[1 - s14R^2]*
Sqrt[1 - s24R2])*(Sqrt[1 - s12R^2]*Sqrt[s24R2] -
Sqrt[1 - s24R2]*s12R*s14R);
gReE[s24R2_, s12R_] := (Sqrt[1 - s14R^2]*Sqrt[1 - s24R2])*(s12R*Sqrt[s24R2] +
Sqrt[1 - s12R^2]*Sqrt[1 - s24R2]*s14R);
gREE[s24R2_, s12R_] := (1 - s14R^2)*(1 - s24R2);

ΔaμZprime[MZprime_, s24L2_, s12L_, s24R2_, s12R_] := -(mmu^2/(8 π^2 MZprime^2))*
(((gLμμ[s24L2, s12L])^2 + (gRμμ[s24R2, s12R])^2)*
F[mmu^2/MZprime^2]
+ ((gLμe[s24L2, s12L])^2 + (gRμe[s24R2, s12R])^2)*
F[me^2/MZprime^2]
+ ((gLμE[s24L2, s12L])^2 + (gRμE[s24R2, s12R])^2)*
F[M4C^2/MZprime^2]
+ mmu/mmu*
Re[gLμμ[s24L2, s12L]*(gRμμ[s24R2, s12R])\[Conjugate]]*
G[mmu^2/MZprime^2]
+ me/mmu*
Re[gLμE[s24L2, s12L]*(gRμE[s24R2, s12R])\[Conjugate]]*
G[me^2/MZprime^2]
+ M4C/mmu*
Re[gLμE[s24L2, s12L]*(gRμμ[s24R2, s12R])\[Conjugate]]*
G[1001^2/MZprime^2])


And then I tried to draw a contour plot by using the defined function but I come up with some problems.

ContourPlot[ΔaμZprime[MZprime, s24L2, 10^-3, 10^-3, 10^-3], {MZprime, 50, 1000}, {s24L2, 0, 1},
ScalingFunctions -> {"Log", "Log"},
FrameLabel -> {Style["\!$$\*SubscriptBox[\(M$$, $$Z'$$]\)[GeV]", FontSize -> 16],
Style["\!$$\*SuperscriptBox[\(sin$$, $$2$$]\)\!$$\*SubscriptBox[\( \ θ$$, $$24 L$$]\)", FontSize -> 16]},
BaseStyle -> {FontFamily -> "Times", FontSize -> 14},
RegionFunction ->
Function[{MZprime, s24L2, 10^-3, 10^-3,
10^-3}, ΔaμZprime[MZprime, s24L2, 10^-3, 10^-3,
10^-3] <= Δamumin],
PlotRange -> {{50, 1000}, {10^-3, 1.0}, All},
ContourShading -> {Opacity[0.4, Blue]}, Contours -> {10},
MaxRecursion -> 5]


I assumed the variables s12L, s24R2, s12R to be 10^-3, 10^-3, 10^-3, respectively and wanted to draw the contour plot with respect to MZprime, s24L2 but mathematica gave me some warning messages like How can I remove the warning messages and draw the right contour plot?

The error message shows where the error is.

So, if you change the part RegionFunction -> Function[{MZprime, s24L2, 10^-3, 10^-3, 10^-3} ,...] to

RegionFunction -> Function[{MZprime, s24L2},
ΔaμZprime[MZprime, s24L2, 10^-3, 10^-3, 10^-3] <= Δamumin]


you get (without error/warning messages) • Great! Thanks for your help. – lhcQFT Jun 17 '19 at 11:17