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arXiv · 1703.06315

Resonance a_1(1420) and the Three-Pion Decays of the Tauon

Peter Lichard
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Abstract

The role of the a_1(1420) resonance in the three-pion decays of the tau lepton is investigated using a phenomenological model. For all data before 2008, roughly equal fit quality is achieved when the basic a_1(1260) resonance is supplemented with either a_1(1640) or a_1(1420). However, two recent and more precise data sets require resonances with masses that are not very far from that of a_1(1420). This suggests that the axial-vector resonance that accompanies the a_1(1260) in the three-pion decays of the tauon is a_1(1420), not a_1(1640), as believed up to now. More data are needed to demonstrate this definitely.

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Peter Lichard. 2017-03-18. Resonance a_1(1420) and the Three-Pion Decays of the Tauon. https://arxiv.org/abs/1703.06315

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