Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1853356 | Physics Letters B | 2007 | 7 Pages |
Abstract
We give a general parameterization of the ÎbâÎ(1520)γ decay amplitude, applicable to any strange isosinglet spin-3/2 baryon, and calculate the branching fraction and helicity amplitudes. Large-energy form factor relations are worked out, and it is shown that the helicity-3/2 amplitudes vanish at lowest order in soft-collinear effective theory (SCET). The suppression can be tested experimentally at the LHC and elsewhere, thus providing a benchmark for SCET. We apply the results to assess the experimental reach for a possible wrong-helicity bâsγ dipole coupling in ÎbâÎ(1520)γâpKγ decays. Furthermore we revisit Îb-polarization at hadron colliders and update the prediction from heavy-quark effective theory. Opportunities associated with bâdγ afforded by high-statistics Îb samples are briefly discussed in the general context of CP and flavour violation.
Related Topics
Physical Sciences and Engineering
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Authors
G. Hiller, M. Knecht, F. Legger, T. Schietinger,