English

Testing for New Couplings in Top Quark Decay

High Energy Physics - Phenomenology 2012-08-27 v2

Abstract

Tests of the Lorentz structure of t --> W b decay will be carried out at the Tevatron, and later at the LHC and at a NLC. To quantitatively assay future measurements of competing observables, we consider the (V-A) coupling values of the helicity decay parameters versus "(V-A) + Single Additional Lorentz Structures". Three phase-type ambiguities exist, but measurement of the sign of the large interference between the W boson longitudinal/transverse amplitudes could exclude the two due dynamically to additional (S+P) and (f_M + f_E) couplings. Sizable T-violation signatures can occur for low-effective mass scales, < 320 GeV, but in most cases can be more simply excluded by 10% precision measurement of the probabilities P(W_L) and P(b_L). Signatures for the presence of T-violation associated with the dynamical phase-type ambiguities, CP-violation signatures, and Lambda_b polarimetry are also discussed.

Keywords

Cite

@article{arxiv.hep-ph/0006342,
  title  = {Testing for New Couplings in Top Quark Decay},
  author = {Charles A. Nelson and L. J. Adler,},
  journal= {arXiv preprint arXiv:hep-ph/0006342},
  year   = {2012}
}

Comments

Reason for Replacement: To supply larger figures and correct some typos. Contributed Paper for ICHEP2000. 3 tables; 8 sets of figures; no macros

R2 v1 2026-07-22T13:27:43.652Z