In electric fields, we usually define the dielectric constant in vacuum as: $$K_C=\dfrac{1}{4\pi\varepsilon_0}$$
Why don't we define the gravitational analogue, "digravitational" constant: $$\Delta_0=\dfrac{1}{4\pi G_N}$$
Is that constant used and have someone defined it before? Surely, it is, but I would like a reference...
