Improved Experimental Test of Time - Reversal Symmetry in ' 9 Ne P Decay

to s,Trio+'4'(y, )4'(y,)]. The expansion of the operator product contains terms proportional to the scalar gluon field y(x) such as Iyi y-. l' "'~ "+'s (y, y-.)ly, -y, l 'J''«~(~)8 (o, y„~y, +(&-~)y, ). This quark-antiquark singularity leads to a term in 6'(x, k) that falls off as 6'„(x,k) ~ Ikl' '"" ' ~ ' = Ikl '. R. Blankenbecler, Phys. Rev. D 8, 287 (1978); S. J. Brodsky, F. E. Close, and J. F. Gunion, Phys. Rev. D 8, 8678 (1978); P. V. Landshoff, J. C. Polkinghorne, pair cross section, corresponding, for example, and R. Short, Nucl. Phys. B28, 225 (1971). to the Feynman diagram in Fig. (b). 3D. Gross and F. grilczek, Phys. Rev. Z,ett. 80, ]848 I thmk J. BjOrken and J. Gunlon for emPhaslz{1978) H. D. Polltzer, Phys. Rev. Lett. BO, 1846 (1978). ing the importance Of final-State jets to me, and S. D. Drell and T.-M. Yan, Phys. Rev. Lett. 25, $16 D. Gross and S. Treiman for helpful critical ad(1970), and Ann, Phys. (N.Y.) 66, 578 (1971). 5G. Farrar, Nucl. Phys. B77, 429 (1974). 6G. Chu and J. F. Gunion, Phys. Rev. D 10, 8672 (1974); J. F. Gunion, Phys. Rev. D 14, 1400 (1976). *Work supported by the National Science Foundation J.B. Kogut and D. E. Soper, Phys. Rev. D 1, 2901 under Grant No. MPS-75-22514. (1970); R. A. Neville and F. Rohrlich, Phys. Rev. D 8, 'R, . p. Feynman, Photon-Hadron Interactions (Benja1882 (1971). min, Reading, Mass. , 1972); J. D. Bjorken, in ProceedJ. D. Bjorken, J. B. Kogut, and D. E. Soper, Phys. ings of the Third International Symposilm on Electron Rev. D 8, l82 (1971). and Photon Interactions at High Energies, Stanford LinD. E. Soper, to be published. ear Accelerator Center, Stanford, California, 1967 That is, "null-plane helicity. " See D. E. Soper, (Clearing House of Federal Scientific and Technical InPhys. Rev. D 5, 1956 (1972). formation, Washington, D. C., 1968); J. D. Bjorken ~~K. Wilson, Phys. Rev. 179, 1499 (1969). and E. A. Paschos, Phys. Rev. 185, 1975 (1969). ~~If one assumes conformal invariance near the light S. D. Drell, D. Levy, and T.-M. Yan, Phys. Rev. cone, one obtains such a representation with a(o. ) 187, 2159 (1969), and Phys. Rev. D 1, 1985 (1970). See known. See S. Ferrsrs, R. Gstto, and A. F. Grillo, the related work of J. F. Gunion, S. J. j3rodsky, and Nucl. Phys. B34, 849 (1971).