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Manuscript Title: PAPH: partial-wave analysis of p-3He scattering.
Authors: M. Matsuda, J. Nagata, H. Yoshino, Y. Yoshino
Program title: PAPH
Catalogue identifier: ADMO_v1_0
Distribution format: tar.gz
Journal reference: Comput. Phys. Commun. 131(2000)264
Programming language: Fortran.
Word size: 32
Keywords: Elementary particle physics, Empirical model, Partial-wave analysis, p-3He, Strong interaction, chi-square-minimization, Error matrix.
Classification: 11.6.

Nature of problem:
Partial-wave analysis (PWA) is a model independent method [1] to determine the scattering amplitudes by means of fitting the experimental data for many kinds of observables. PAPH can carry out the energy-independent PWA of p-3He scattering [2]. The obtained phase shifts can be used to construct the p-3He potential for studying the n+p+3He system with various models of three body problem.

Solution method:
The available experimental data are stored in the input file for PAPH. The chi-square-minimizing search is carried out [3] and the free searched parameters are varied so as to reproduce the experimental data. After completing the chi-square-minimizing search, the user obtains the best-fit values of parameters (phase shifts, mixing parameters and reflection parameters) together with their uncertainties simultaneously. PAPH provides the solution of phase shifts, mixing parameters, reflection parameters and also the determined helicity amplitudes. In addition, the calculated values of the differential cross section and various spin observables are provided. New experiments may be proposed by studying the predicted values for spin observables by PAPH.

Restrictions:
Only the published observables can be analyzed by PAPH. If some new observable is provided, a subroutine CROSE and the related subprograms for inputting the data and outputting the observables (see Section 4) should be modified to include them in the analysis.

References:
[1] H.P. Stapp, T.J. Ypsilantis, N. Metropolis, Phys. Rev. 105 (1957) 33.
[2] Y. Yoshino, V. Limkaisang, J. Nagata, H. Yoshino, M. Matsuda, Progr. Theor. Phys. 103 (2000) 107.
[3] Y. Oyanagi, Library of Computer Center of University of Tokyo; M.J.D. Powell, Computer Journal 7 (1965) 303.