Inclusive eta' Production from the Upsilon(1S)

TL;DR

This paper measures the eta' gluon-gluon form-factor in Upsilon(1S) decays to explore its role in B meson decay rates, finding no evidence for anomalous couplings and suggesting the need for new physics explanations.

Contribution

It provides the first measurement of the eta' - gluon - gluon form-factor in Upsilon(1S) decays, constraining models of eta' production and B decay anomalies.

Findings

No evidence for large anomalous couplings at high q^2

Results challenge explanations of large B -> Xs eta' rates within Standard Model

Data suggest alternative, possibly non-Standard Model, mechanisms are needed.

Abstract

Using the CLEO II detector at CESR, we measure the eta' - gluon - gluon form-factor in Y(1S) decays. This form-factor especially at large eta' energies may provide an explanation of the large rate for B -> Xs eta'. Our data do not support a large anomalous coupling at higher q^2 and thus the large eta' rate remains a mystery, possibly requiring a non-Standard Model explanation.