Determinations of and from baryonic decays

Y. K. Hsiao; C. Q. Geng

doi:10.1140/epjc/s10052-017-5271-1

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2024 Impact factor 4.8

Particles and Fields

Open Access

Eur. Phys. J. C (2017) 77: 714
https://doi.org/10.1140/epjc/s10052-017-5271-1

Regular Article - Theoretical Physics

Determinations of $|V_{cb}|$ and $|V_{ub}|$ from baryonic $\Lambda _b$ decays

Y. K. Hsiao¹^,2 and C. Q. Geng¹^,2^,3^*

¹ School of Physics and Information Engineering, Shanxi Normal University, Linfen, 041004, China
² Department of Physics, National Tsing Hua University, Hsinchu, 300, Taiwan
³ Synergetic Innovation Center for Quantum Effects and Applications (SICQEA), Hunan Normal University, Changsha, 410081, China

^* e-mail: geng@phys.nthu.edu.tw

Received: 1 August 2017
Accepted: 1 October 2017
Published online: 26 October 2017

Abstract

We present the first attempt to extract $|V_{cb}|$ from the $\Lambda _b\rightarrow \Lambda _c^+\ell \bar{\nu }_\ell$ decay without relying on $|V_{ub}|$ inputs from the B meson decays. Meanwhile, the hadronic $\Lambda _b\rightarrow \Lambda _c M_{(c)}$ decays with $M=(\pi ^-,K^-)$ and $$M_c=(D^-,D^-_s)$$ measured with high precisions are involved in the extraction. Explicitly, we find that $|V_{cb}|=(44.6\pm 3.2)\times 10^{-3}$ , agreeing with the value of $(42.11\pm 0.74)\times 10^{-3}$ from the inclusive $B\rightarrow X_c\ell \bar{\nu }_\ell$ decays. Furthermore, based on the most recent ratio of $|V_{ub}|/|V_{cb}|$ from the exclusive modes, we obtain $|V_{ub}|=(4.3\pm 0.4)\times 10^{-3}$ , which is close to the value of $(4.49\pm 0.24)\times 10^{-3}$ from the inclusive $B\rightarrow X_u\ell \bar{\nu }_\ell$ decays. We conclude that our determinations of $|V_{cb}|$ and $|V_{ub}|$ favor the corresponding inclusive extractions in the B decays.