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arXiv · 1010.1552

Rotation-invariant observables in parity-violating decays of vector particles to fermion pairs

Pietro Faccioli·Carlos Lourenco·Joao Seixas·Hermine K. Woehri
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Abstract

The di-fermion angular distribution observed in decays of inclusively produced vector particles is characterized by two frame-independent observables, reflecting the average spin-alignment of the produced particle and the magnitude of parity violation in the decay. The existence of these observables derives from the rotational properties of angular momentum eigenstates and is a completely general result, valid for any J=1 state and independent of the production process. Rotation-invariant formulations of polarization and of the decay parity-asymmetry can provide more significant measurements than the commonly used frame-dependent definitions, also improving the quality of the comparisons between the measurements and the theoretical calculations.

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Pietro Faccioli, Carlos Lourenco, Joao Seixas, Hermine K. Woehri. 2010-10-07. Rotation-invariant observables in parity-violating decays of vector particles to fermion pairs. https://doi.org/10.1103/physrevd.82.096002

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