Determination of the H2-H2 potential from absolute integral cross section measurements

Absolute integral cross sections have been measured for n-H₂-n-H₂ at primary particle velocities between 1270 and 9650 m/sec with a 77 °K target. The number density of target particles was determined with an accuracy of 1% by the method of dynamic expansion. The velocity dependence of the integral cross section was also measured for the isotopic systems n-D₂-n-H₂ and n-D₂-n-D₂ at primary beam velocities between 280 and 1170 m/sec with a 15 °K target. All available integral cross section data are compared with literature potentials. A new potential is proposed, which exhibits one bound state for H₂-H₂.Dedicated to Professor H. Hartmann on his 60^th birthday.     

Greedy matching on a grid

A fast solution to the complete minimum matching problem using a greedy heuristic is presented, when the points are distributed on a grid domain. For this a data structure which efficiently supports nearest neighbor searches and deletions from a planar point set is developed.     

A completeness theorem for operator spaces

A theorem concerning the completeness of operator manifolds used for the generation of ionized electronic states by direct methods is formulated and proven.