Fred ,
Below is a reply from Eric Lerner inregard to your post below
>Hi Richard,
>Actually reaction rates are not just a product of Coulomb barrier. At 200keV the reaction rate for pB11 is nearly 4 times that for >Li-P. Also, the compression in a DPF improves with increasing nuclear mass and charge. These factor tend to compensate >for lithium's lesser x-ray emission. Eric
Fred wrote..
The electrostatic repulsive force (coulomb barrier) between
a proton (Z =1) and the boron nucleus (Z = 5 ) at an approach
distance d, is 1 * 5 * kq^2/d^2 = 1,152 newtons (258 pounds) at
d = 1.0e-15 meters or 0.00115 newtons at d = 1.0e-12 meters.
3/5th of that for the Proton 7 Lithium barrier, 2/5th for Deuterium -3 Helium
and 1/5th for the D-D or D-T coulomb barrier,
Quite a hill to climb. Cockcroft and Walton bombarded boron with
500 KeV protons in 1926 and got miniscule quantities of fusion reactions.
Wish them luck with their "Billion Degree" (100 KeV) Focus Fusion device
where the protons and the boron nuclei are all going in the same direction. :-)
Fred