Symbolic Integration

I want to integrate the foll0wing expression to get a symbolic expression of the integration:

Integrate[
1.0/( 4.0*
Pi*((rr*rr) + (8.3*8.3) + (zz*zz) - (2.0*rr*8.3*Cos[ttt])))*
HeavisideTheta[
ArcSin[zz/(((rr*rr) + (8.3*8.3) + (zz*zz) - (2.0*rr*8.3*
Cos[ ttt]))^0.5)] - 20 Degree], {ttt, 0, 2*Pi}]


I want to get the expression in terms of rr and zz. Here rr, zz and ttt are threee variables. But I want to integrate for ttt varable for 0 to 2*Pi. Can anyone help me in this regard?

int[rr_, zz_] :=NIntegrate[1.0/(4.0*Pi*((rr*rr) + (8.3*8.3) + (zz*zz) - (2.0*rr*8.3*Cos[ttt])))*HeavisideTheta[ArcSin[zz/(((rr*rr) + (8.3*8.3) + (zz*zz) - (2.0*rr*8.3*Cos[ttt]))^0.5)] - 20 Degree], {ttt, 0, 2*Pi}]

Plot3D[int[r, z], {r, -3, 3}, {z, 0, 10}, AxesLabel -> {rr, zz}]