I'll post here for the maximum...
It's complex, I bitched about it then because I didn't get the info I needed in my textbooks...
I had to assume gaussian distribution (bell-shaped curve) would be the norm for all multi-particle collisions, (it's based on laws involving average kinetic energy for particles in air... related to diffusion, etc.) beta-decay is a collision, in a sense. (you see the non-syllabus stuff I had to write?)
I fudged some of the answer, and just stated reasons why most of the parrticles had to have much less than the maximum. These include: some beta-decays release EMR, up to gamma wavelength / There's a second particle involved, the antineutrino, which must also share in the energy, and all neutrinos are observed to travel very fast / In conditions where both laws of conservation held, I thought the relationship of 1/2 mv^2 and mv meant that particles would be likely have a low velocity instead of a high one.
I need somebody with a real answer... where's spice girl
?