How do I obtain the value for the Fermi Coupling Constant?

Question

I have been given an equation, without an explanation on the constant included.
The equation is the following: $$Gamma= frac{7pi}{24} G^2_{text{Fermi}}$$
When looking for a value for the Fermi Coupling Constant, $G_{text{Fermi}}$ , I only seem to find values for $G_{text{Fermi}}/{(hbar c)^3}$.
To obtain the value for  $G_{text{Fermi}}$,must I just multiply the value I have for $G_{text{Fermi}}/{(hbar c)^3}$ by $(hbar c)^3$ (the product of plancks constant with the speed of light)?
If so, why is the value of the constant shown in this form , divided by another constant, instead of just being presented as itself?

mike stone · Accepted Answer

Most particle theory texts use "natural units" units are such that $hbar c$ is numerically unity, although it has dimensions $ML^2T^{-2}$ of energy.  $G_0= G_F/(hbar c)^3$ is usually quoted  units of $GeV^{-2}$. This tells us that $G_F$ itself has units of $GeV$.
You do not tell us what $Gamma$ is. Is it a decay width? If so, it has dimensions of energy and you probably need $G_F$, and not $G_F^2$ or  $G_0$. Anyway knowing the dimensions of $Gamma$ will tell you.

How do I obtain the value for the Fermi Coupling Constant?

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