Angular asymmetries in $B\to\Lambda\bar p M$ decays

TL;DR

This paper predicts angular asymmetries in specific baryonic B meson decays, highlighting potential experimental tests and the role of baryonic form factors in these processes.

Contribution

It provides the first predictions of angular asymmetries involving vector mesons in charmless baryonic B decays, emphasizing the importance of baryonic form factors.

Findings

Predicted ${ m A}_{FB}$ as large as -14.6% for certain decays.

First prediction of ${ m A}_{FB}$ involving vector mesons in these decays.

Experimental facilities like LHCb and Belle II can test these predictions.

Abstract

The forward-backward angular asymmetry (${\cal A}_{FB}$) for $\bar B^0\to \Lambda\bar p\pi^+$ measured by Belle has presented an experimental value in the range of $-30\%$ to $-50\%$. In our study, we find that ${\cal A}_{FB}[\bar B^0\to\Lambda\bar p \pi^+(B^-\to \Lambda\bar p\pi^0)]$ can be as large as $(-14.6^{+0.9}_{-1.5}\pm 6.9)\%$. In addition, we present ${\cal A}_{FB}[\bar B^0\to\Lambda\bar p \rho^+(B^-\to \Lambda\bar p\rho^0)] =(4.1^{+2.8}_{-0.7}\pm 2.0)\%$ as the first prediction involving a vector meson in the charmless $B\to{\bf B\bar B'}M$ decays. While ${\cal A}_{FB}(B\to\Lambda\bar p M)$ indicates an angular correlation caused by the rarely studied baryonic form factors in the timelike region, LHCb and Belle~II are capable of performing experimental examinations.