Publication

Observation of the Radiative Decays of Upsilon(1S) to chi(c1)

Mingkui Wang, Olivier Schneider, Chao Wang, Yiming Li, Sun Hee Kim
2020
Journal Articles

Abstract

We report the first observation of the radiative decay of the Upsilon(1S) into a charmonium state. The significance of the observed signal of Upsilon(1S) -> gamma chi(c1) is 6.3 standard deviations including systematics. The branching fraction is calculated to be B[Upsilon(1S) -> gamma chi(c1)] = [4.7(-1.8)(+2.4) (stat)(-0.5)(+0.4) (sys) x 10(-5)]. We also searched for Upsilon(1S) radiative decays into chi(c0.2) and eta(c)(1S, 2S), and set upper limits on their branching fractions. These results are obtained from a 24.9 fb(-1) data sample collected with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider at a center-of-mass energy equal to the Upsilon(2S) mass using Upsilon(1S) tagging by the Upsilon(2S) -> Upsilon(1S)pi(+)pi(-) transitions.

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https://infoscience.epfl.ch/entities/publication/b1fa6323-5716-4787-8353-ec6f7222057a

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Mingkui Wang, Olivier Schneider, Chao Wang, Yiming Li, Sun Hee Kim
2020
Journal Articles

Abstract

Official source

https://infoscience.epfl.ch/entities/publication/b1fa6323-5716-4787-8353-ec6f7222057a

About this result

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