State-Dependent Recombination and Suppressed Nuclear Relaxation in Atomic Hydrogen

A gas of 99.8% electron- and nuclear-spin-polarized hydrogen has been prepared. The surface and volume nuclear relaxation rates have been measured and the magnetic field dependence ${(1+\frac{16.68}{B})}^2$ has been confirmed. The ratio of the surface recombination rate constants for collisions between atoms in hyperfine states, $a-a$ and $a-b$, is measured to be 2.23(25). Nuclear relaxation on the surface has been suppressed by using ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ to make an atomically flat surface.