New algorithms for identifying the flavour of $B^0$ mesons using pions and protons

TL;DR

This paper introduces two novel algorithms for determining the initial flavour of $B^0$ mesons in proton-proton collisions, enhancing tagging power and pioneering proton-based identification methods.

Contribution

It presents the development, optimization, and calibration of new algorithms using pions and protons for $B^0$ flavour tagging in collider data, including the first proton-based method.

Findings

Pion algorithm's tagging power increased by 60%.

Proton algorithm is the first of its kind for $B^0$ flavour tagging.

Algorithms are calibrated on LHCb data at 7 and 8 TeV.

Abstract

Two new algorithms for use in the analysis of $pp$ collision are developed to identify the flavour of $B^0$ mesons at production using pions and protons from the hadronization process. The algorithms are optimized and calibrated on data, using $B^0 \rightarrow D^- \pi^+$ decays from $pp$ collision data collected by LHCb at centre-of-mass energies of 7 and 8 TeV. The tagging power of the new pion algorithm is 60 % greater than the previously available one; the algorithm using protons to identify the flavour of a $B^0$ meson is the first of its kind.