The effect of long-range forces on cold-atomic interaction: Ps-H system
  The s-wave elastic phase-shifts and s-wave elastic cross sections are studied to find the effect of long-range forces on cold-atomic interactions using a modified static-exchange model for Ps-H system. A Feshbach resonance in the triplet channel using the modified static-exchange model at the energy ~ 3x10^{-6} eV caused by long-range forces in the Ps-H system is being reported. 
Hasi Ray
physics.atom-ph