A deuteron is is the
only two-nucleon bound state.
It is the simplest
nucleus. It plays a role in nuclear physics that that resembles the role the hydrogen atom plays in
atomic physics.
It is a nucleus of
deuterium (21H)--an isotope of hydrogen with an abundance of
0.015%.
It consists of a proton
and neutron with total spin S=1 (parallel), a total angular momentum
J=1, and angular momentum ℓ =0 ,2.
It is a coupled state of mostly 3S1 and a small admixture of 3D1.
Using a novel algorithm by a Padua Group a coupled Schrφdinger Equation (AKA Rarita-Schwinger Equation[RSE]) can be solved to obtain a pair of wave functions u(3S1) and w(3D1) as eigenvectors and the binding
energy as an eigenvalue.