Friedman, J.I.; Telegdi, V.L.; Nuclear Emulsion Evidence for Parity Nonconservation in the Decay Chain ++e+
Phys. Rev. 105 (1957) 1681;
R. N. Cahn and G. Goldhaber, The Experimental Foundations of Particle Physics, Cambridge Univ. Press (1991) 176.
The Physical Review - the First Hundred Years, AIP Press (1995) CD-ROM.
Preliminary data on 1300 decays in magnetically-shielded emulsions exposed to the Chicago synchrocyclotron are consistent with an angular distribution W() = 1 - 0.12 cos . The formation of "muonium'' (+ e-) may be an important cause of depolarization in such experiments. (Science Abstracts, 1957, 5643. K. H. Barker.).
Related references More (later) information appears in T. D. Lee, R. Oehme, and C. N. Yang, Phys. Rev. 106 (1957) 340;
See also S. Berko and F. Hereford, Rev. of Mod. Phys. 28 (1956) 299;
V. L. Telegdi, J. C. Seng, and D. D. Yovanovitch, Phys. Rev. 104 (1956) 867;
T. D. Lee and C. N. Yang, Phys. Rev. 104 (1956) 254;
Analyse data from R. L. Garwin, L. M. Lederman, and M. Weinrich, Phys. Rev. 105 (1957) 1415;
Confirmation of parity nonconservation in weak decays.