Observation of New Charmless Decays of Bottom Hadrons

TL;DR

This paper reports the first observation of several new charmless decays of bottom hadrons, including ext{B}_s^0 o K ext{pi} and charmless ext{b}-baryon decays, with measured branching fractions and significance levels.

Contribution

It presents the first observation and measurement of specific charmless bottom hadron decays using data from the Fermilab Tevatron, expanding knowledge of bottom hadron decay modes.

Findings

Observation of ext{B}_s^0 o K ext{pi} with 8.2σ significance.

First observation of ext{b}-baryon decays ext{L}_b^0 o p ext{pi} and ext{L}_b^0 o pK with high significance.

Set upper limit on ext{B}_d^0 o K K} decay branching fraction.

Abstract

We search for new charmless decays of neutral $b$--hadrons to pairs of charged hadrons with the upgraded Collider Detector at the Fermilab Tevatron. Using a data sample corresponding to 1 fb$^{-1}$ of integrated luminosity, we report the first observation of the \BsKpi decay, with a significance of $8.2\sigma$, and measure $\BR(\BsKpi) = (5.0 \pm 0.7\stat \pm 0.8\syst)\times 10^{-6}$. We also report the first observation of charmless $b$--baryon decays in the channels \Lbppi and \LbpK with significances of $6.0\sigma$ and $11.5\sigma$ respectively, and we measure $\BR(\Lbppi) = (3.5 \pm 0.6\stat \pm 0.9\syst)\times 10^{-6}$ and $\BR(\LbpK) = (5.6 \pm 0.8\stat \pm 1.5\syst)\times 10^{-6}$. No evidence is found for the decays \BdKK and \Bspipi, and we set an improved upper limit $\BR(\Bspipi) < 1.2\times 10^{-6}$ at the 90% confidence level. All quoted branching fractions are measured using $\BR(\BdKpi)$ as a reference.