form factors and decays into in covariant light-front approach

Yu-Ji Shi; Wei Wang; Zhen-Xing Zhao

doi:10.1140/epjc/s10052-016-4405-1

EPJ

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2023 Impact factor 4.2

Particles and Fields

Open Access

Eur. Phys. J. C (2016) 76: 555
https://doi.org/10.1140/epjc/s10052-016-4405-1

Regular Article - Theoretical Physics

$B_c\rightarrow B_{sJ}$ form factors and decays into $B_{sJ}$ in covariant light-front approach

Yu-Ji Shi¹, Wei Wang¹^,2 and Zhen-Xing Zhao¹^*

¹ INPAC, Shanghai Key Laboratory for Particle Physics and Cosmology, Department of Physics and Astronomy, Shanghai Jiao-Tong University, Shanghai, 200240, China
² State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing, 100190, China

^* e-mail: star_0027@sjtu.edu.cn

Received: 6 July 2016
Accepted: 26 September 2016
Published online: 12 October 2016

Abstract

We suggest to study the $B_{s}$ and its excitations $B_{sJ}$ in the $$B_c$$ decays. We calculate the $B_c\rightarrow B_{sJ}$ and $B_c\rightarrow B_{J}$ form factors within the covariant light-front quark model, where the $B_{sJ}$ and $B_{J}$ denote an s-wave or p-wave $\bar{b}s$ and $\bar{b}d$ meson, respectively. The form factors at $$q^2=0$$ are directly computed while their $$q^2$$ -distributions are obtained by extrapolation. The derived form factors are then used to study semileptonic $B_c\rightarrow (B_{sJ},B_{J})\bar{\ell }\nu$ decays, and nonleptonic $B_c\rightarrow B_{sJ}\pi$ . Branching fractions and polarizations are predicted in the standard model. We find that the branching fractions are sizable and might be accessible at the LHC experiment and future high-energy $$e^+e^-$$ colliders with a high luminosity at the Z-pole. The future experimental measurements are helpful to study the nonperturbative QCD dynamics in the presence of a heavy spectator and also of great value for the study of spectroscopy.