IE3D capacitor simulation

Dear Sirs, I simulate a simple capacitor with plates of 4x2 mm and 5um of dielectric (dielectric constant=3.8).
The 2-port PI with Shunt RC and Shunt RC model give me a correct value of 54 pf but R is 22987 Ohm.
Why R is so low? I expected a more high value.
What is R in Shunt RC model?
Thanks
Ettore.

I guess the R depends on the loss of the dielectric.. Had you selected a dielectric with higher loss tangent, you would have got higher R..Equivalent R signifies the dielectric loss.

Thanks Catherine for you reply.
At first I also thought of the loss in the dielectric.
But I believe that these losses occur at high frequencies.
I simulated the capacity from 10 MHz to 100 MHz frequency range.
I tried to simulate the capacitor with different TanD(E).
The R values between two capacitor plates are (@ 10 MHz):
TanD(E)=0.05 R=5780 Ohm
TanD(E)=0.001 R= 163380 Ohm
TanD(E)=0 , so no dielectric loss , R=360000 Ohm
Still, the R value seems too low to me.
Maybe R value depends on loss tangent and something else that I don't know.

Ettore.

Hello everyone, no suggestions, explanation ?