ISOLATED RESONANCE DECOMPOSITION OF A MULTICHANNEL S-MATRIX - A TEST FROM THE SCATTERING OF H+CO REVERSIBLE HCO

We report a full test of the decomposition of a multichannel S matrix in the case of isolated resonances by analysis of coupled-channel scattering calculations for H + CO reversible HCO with zero total angular momentum on a realistic potential energy surface. The decomposition of S into resonant and a nonresonant matrices [K. W. McVoy, in Fundamentals in Nuclear Theory, edited by A. de-Shalit and C. Villi (International Atomic Energy Agency, Vienna, 1967) and B. Gazdy and J. M. Bowman, Phys. Rev. A 36, 3083 (1987)] developed in the limit of an infinitely narrow isolated resonance is applied to the nine calculated resonances determined in the first 1200 cm-1 of collision energy. These resonances have widths varing from 10(-6) to 10(0) cm-1. Time-reversal, conservation, orthogonality and energy-dependence properties of the resulting decomposed matrices are compared to theoretical expectations. The effect on these comparisons of a six order of magnitude variation in resonance width is examined. The special role of orthogonality properties in setting limits to decay distributions without specific knowledge of resonance location or width is discussed.