AN ENERGY-DEPENDENT PHASE-SHIFT ANALYSIS OF LOW-ENERGY PROTON-DEUTERON ELASTIC-SCATTERING

An energy dependent phase shift analysis of p+d elastic scattering bel ow the deuteron breakup threshold has been conducted. The phases are f it directly to the data with a Monte Carlo Markov Chain algorithm afte r being sampled from a parameter space which is constrained to satisfy the Coulomb-modified effective range expansion. The mixing parameters are required to obey analyticity constraints. The overall fit in the preliminary analysis reported here was satisfactory, giving a chi(2)/d atum of about 2.5. The analysis indicates the existence of a singulari ty in the spin-doublet S-wave effective range function. The inferred v alue of the quartet S-wave scattering length is in excellent quantitat ive agreement with theoretical predictions. Small changes to the theor etical P-wave phase shifts and somewhat larger changes to the theoreti cal J = 1/2 mixing parameters are required to reproduce the p+d data.