Predictions for the isospin-violating decays of Bc(1P)⁺→ Bc(*)+π⁰

In this work we study the isospin-violating decays of Bc(1P)⁺→ Bc(*)+π⁰, which may provide additional information for the determination of the properties of the first orbital excitation states of Bc(1P)⁺. By assuming a dual relation between the U(1) anomaly soft-gluon coupling for Bc(1P)⁺→ Bc(*)+π⁰ and the intermediate meson loop transitions, we can quantify the isospin-violating decay effects for these four P-wave states. We find that the partial decay width of Bc0*+→ Bc⁺π⁰ is about three orders of magnitude larger than that for Bc2*+→ Bc⁺π⁰. It implies that Bc0*+ can be established in the Bc⁺π⁰ decay channel as a single state. Meanwhile, the two axial-vector states Bc1⁺/Bc1'⁺ can be possibly identified in Bc1⁺/Bc1'⁺→ Bc*+π⁰ with comparable strengths. Although these isospin-violating decays turn out to be small, the theoretical predictions should be useful for guiding future experimental efforts. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. Article funded by SCOAP3 and published under licence by Chinese Physical Society and the Institute of High Energy Physics of the Chinese Academy of Science and the Institute of Modern Physics of the Chinese Academy of Sciences and IOP Publishing Ltd.