Measurement of Spin Correlation coefficients in \vec p \vec p --> d pi^+

B. v. Przewoski; J. T. Balewski; J. Doskow; H. O. Meyer; R. E. Pollock; T. Rinckel; P. Thörngren-Engblom; A. Wellinghausen; W. Haeberli; B. Lorentz; F. Rathmann; B. Schwartz; T. Wise; W. W. Daehnick; Swapan K. Saha; P. V. Pancella

doi:10.1103/physrevc.61.064604

arXiv · nucl-ex/9912008

Measurement of Spin Correlation coefficients in \vec p \vec p --> d pi^+

B. v. Przewoski·J. T. Balewski·J. Doskow·H. O. Meyer·R. E. Pollock·T. Rinckel·P. Thörngren-Engblom·A. Wellinghausen·W. Haeberli·B. Lorentz·F. Rathmann·B. Schwartz·T. Wise·W. W. Daehnick·Swapan K. Saha·P. V. Pancella

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Abstract

The spin correlation coefficent combinations A_{xx}+A_{yy} and A_{xx}-A_{yy}, the spin correlation coefficients A_{xz} and A_{zz}, and the analyzing power were measured for \vec p \vec p --> d pi^+ between center-of-mass angles 25 deg \leq θ\leq 65 deg at beam energies of 350.5, 375.0 and 400.0 MeV. The experiment was carried out with a polarized internal target and a stored, polarized beam. Non-vertical beam polarization needed for the measurement of A_{zz} was obtained by the use of solenoidal spin rotators. Near threshold, only a few partial waves contribute, and pion s- and p-waves dominate with a possible small admixture of d-waves. Certain combinations of the observables reported here are a direct measure of these d-waves. The d-wave contributions are found to be negligible even at 400.0 MeV.

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B. v. Przewoski, J. T. Balewski, J. Doskow, H. O. Meyer, R. E. Pollock, T. Rinckel, P. Thörngren-Engblom, A. Wellinghausen, W. Haeberli, B. Lorentz, F. Rathmann, B. Schwartz, T. Wise, W. W. Daehnick, Swapan K. Saha, P. V. Pancella. 1999-12-16. Measurement of Spin Correlation coefficients in \vec p \vec p --> d pi^+. https://doi.org/10.1103/physrevc.61.064604

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