A method is presented for completely removing the ambiguities arising in the reconstruction of the nucleon-nucleon scattering matrix from data at a given angle and energy due to the bilinear form of expressions for observable quantities. Our method utilizes only the amplitudes defined by Wolfenstein and Ashkin and is more direct and computationally simpler than the methods using unitarity and measurements at all angles or the phase-shift analyses; thus, it would provide an independent means of arriving at the correct set of phase-shift solutions. Our method is based on a knowledge of the polarization transfer tensor , which has a form complementary to the familiar polarization correlation tensor . The tensor may be obtained from triple scattering experiments on the recoil nucleon similar to those used to determine the familiar depolarization tensor , or from double scattering measurements on nucleons scattered from a polarized target.
It is also shown that the use of polarized targets would have many experimental advantages: They would permit (1) determination of the depolarization tensor for large scattering angles, without requiring the measurement of the polarization of a very slow nucleon; (2) determination of the correlation tensor by the measurement of the cross section for the scattering of a polarized beam by a polarized target, instead of the difficult simultaneous measurements of the polarizations of both the final nucleons; (3) determination of the "difficult" components and of the and tensors by the measurement of the polarization of an initially unpolarized beam scattered by a polarized target.
- Received 31 October 1960
- Published in the issue dated March 1961
© 1961 The American Physical Society