Radiative Decays of the Upsilon(1S) to a Pair of Charged Hadrons

TL;DR

This paper reports on measurements of radiative decay modes of the Upsilon(1S) into pairs of charged hadrons, providing branching ratios, helicity ratios, and upper limits for various decay channels using data from the CLEO-III detector.

Contribution

It presents new experimental measurements of exclusive radiative Upsilon(1S) decays into specific hadronic final states, including branching ratios and upper limits for rare decay modes.

Findings

Branching ratios for Upsilon(1S) to gamma f_2(1270) and gamma f_2'(1525) measured.

Helicity production ratios for f_2(1270) and f_2'(1525) determined.

Upper limits set for decays involving f_J(2200) and X(1860).

Abstract

Using data obtained with the CLEO~III detector, running at the Cornell Electron Storage Ring (CESR), we report on a new study of exclusive radiative Upsilon(1S) decays into the final states gamma pi^+ pi^-, gamma K^+ K^-, and gamma p pbar.. We present branching ratio measurements for the decay modes Upsilon(1S) to gamma f_2(1270), Upsilon(1S) to gamma f_2'(1525), and Upsilon(1S) to gamma K^+K^-; helicity production ratios for f_2(1270) and f_2'(1525); upper limits for the decay Upsilon(1S) to gamma f_J(2200), with f_J(2220) to pi^+ pi^-, K^+ K^-, p pbar; and an upper limit for the decay Upsilon(1S) to gamma X(1860), with X(1860) to gamma p pbar.