Model-independent predictions for decays of double-heavy hadrons into pairs of heavy hadrons

TL;DR

This paper derives model-independent selection rules for the decays of double-heavy hadrons into pairs of heavy hadrons, based on Born-Oppenheimer potentials, quantum number constraints, and angular momentum conservation, applicable to baryons and tetraquarks.

Contribution

It introduces a framework for decay predictions of double-heavy hadrons that does not depend on specific models, using Born-Oppenheimer potentials and symmetry principles.

Findings

Derived selection rules for decay processes.

Expressed coupling potentials as sums of transition amplitudes and angular coefficients.

Discussed decay rates for double-heavy baryons and tetraquarks.

Abstract

Double-heavy hadrons can decay into pairs of heavy hadrons through transitions from confining Born-Oppenheimer potentials to heavy-hadron-pair potentials with the same Born-Oppenheimer quantum numbers. The states of the double-heavy hadron are constrained by a Born-Oppenheimer exclusion principle from the identical heavy quarks. The states of a pair of identical heavy hadrons are constrained by exclusion principles from identical particles. The transitions are also constrained by conservation of angular momentum and parity. From these constraints, we derive model-independent selection rules for decays of double-heavy hadrons into pairs of heavy hadrons. The coupling potentials are expressed as sums of products of Born-Oppenheimer transition amplitudes and angular-momentum coefficients. If there is a single dominant Born-Oppenheimer transition amplitude, it factors out of the coupling potentials between double-heavy hadrons in the same Born-Oppenheimer multiplet and pairs of heavy hadrons in specific heavy-quark-spin-symmetry multiplets and out of the corresponding partial decay rates. As examples, we discuss the Born-Oppenheimer potentials and multiplets for conventional double-heavy baryons and for double-heavy tetraquark mesons. We also discuss the relative partial decay rates for conventional double-heavy baryons into pairs of heavy hadrons.