Kappa = Sqrt((2(469.4MeV/3.0*10^8m.s^-2)*2.226Mev)/(6.5817*10^-22MeV.s)^2 = 5939.86
-Kappa*R = 5939.86*1.5*10^-13 = 8.90*10^-13
I'm trying to convert the fm into cm
I'm trying to solve for this in a deuteron problem. But can't seem to get the right answer.
The reduced mass of the deuteron is 469.4 MeV, the binding energy Eb is 2.226 MeV and R = 1.5fm.
Using hbar = 6.5817x10^-16 eV.s
I get Kappa = sqrt((2(469.4)*2.226)/(6.5817*10^-22)^2) = 6.94*10^16...
Here's the problem:
It is more common to define the “effective number of relativistic degrees of freedom” by writing the total radiation energy as ρR = ργ + ρν + ρe± = (π^2/30) g∗*T^4 , where g∗ = 2 + 7/8(6 + 4) = 43/4 . (1.52) With this, the expansion rate during the radiation era is given by...