Inclusive chi_bJ(nP) Decays to D0 X

TL;DR

This paper investigates chi_bJ(nP) decays to open charm using CLEO III data, confirming NRQCD predictions that J=1 states produce the most charm, with about 25% of decays involving c cbar g.

Contribution

First measurement of chi_bJ(nP) decays to open charm, providing data to fit non-perturbative NRQCD parameters and confirming theoretical predictions.

Findings

Significant signals for J=1 states in chi_bJ decays.

Results agree with NRQCD predictions for charm production.

Charm production accounts for about 25% of hadronic decays for J=1.

Abstract

Using Upsilon(2S) and Upsilon(3S) data collected with the CLEO III detector we have searched for decays of chi_bJ to final states with open charm. We fully reconstruct D0 mesons with p_D0 > 2.5 GeV/c in three decay modes (K-pi+, K-pi+pi0, and K-pi-pi+pi+) in coincidence with radiative transition photons that tag the production of one of the chi_bJ(nP) states. We obtain significant signals for the two J=1 states. Recent NRQCD calculations of chi_{bJ}(nP) --> c cbar X depend on one non-perturbative parameter per chi_bJ triplet. The extrapolation from the observed D0 X rate over a limited momentum range to a full c cbar X rate also depends on these same parameters. Using our data to fit for these parameters, we extract results which agree well with NRQCD predictions, confirming the expectation that charm production is largest for the J=1 states. In particular, for J=1, our results are consistent with c cbar g accounting for about one-quarter of all hadronic decays.