TY - JOUR

T1 - S-channel helicity conservation in elastic processes

AU - Langacker, Paul

PY - 1972

Y1 - 1972

N2 - The unitarity equation for elastic partial-wave amplitudes is considered. Defining helicity-total-flip elastic amplitudes as those in which both helicities change sign, it is observed that the unitarity equation strongly suggests that the imaginary part of the helicity-total-flip partial-wave amplitude is much smaller than that of the nonflip amplitude at high energies. Appealing to a plausibility argument, the ratio of helicity-total-flip to helicity-nonflip partial-wave amplitudes is estimated to be (1s)12 or smaller. The implications of this result for the full amplitude, the possibility of extending the result to other amplitudes if factorization is true, and the implications for Regge theory are discussed.

AB - The unitarity equation for elastic partial-wave amplitudes is considered. Defining helicity-total-flip elastic amplitudes as those in which both helicities change sign, it is observed that the unitarity equation strongly suggests that the imaginary part of the helicity-total-flip partial-wave amplitude is much smaller than that of the nonflip amplitude at high energies. Appealing to a plausibility argument, the ratio of helicity-total-flip to helicity-nonflip partial-wave amplitudes is estimated to be (1s)12 or smaller. The implications of this result for the full amplitude, the possibility of extending the result to other amplitudes if factorization is true, and the implications for Regge theory are discussed.

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U2 - 10.1103/PhysRevD.5.2864

DO - 10.1103/PhysRevD.5.2864

M3 - Article

AN - SCOPUS:35949031746

VL - 5

SP - 2864

EP - 2868

JO - Physical review D: Particles and fields

JF - Physical review D: Particles and fields

SN - 1550-7998

IS - 11

ER -