Prefer a chat interface with context about you and your work?
Branching fractions for<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>ψ</mml:mi><mml:mn /><mml:mo>(</mml:mo><mml:mn>2</mml:mn><mml:mi>S</mml:mi><mml:mo>)</mml:mo><mml:mn /><mml:mo>→</mml:mo><mml:mi>γ</mml:mi><mml:mrow><mml:msup><mml:mrow><mml:mi>η</mml:mi></mml:mrow><mml:mrow><mml:mo>′</mml:mo></mml:mrow></mml:msup></mml:mrow></mml:math>and γη
We report first measurements of the branching fractions B(ψ2S→γη′)=(1.54±0.31±0.20)×10−4 and B(ψ2S→γη)=(0.53±0.31±0.08)×10−4. The ψ(2S)→γη′ result is consistent with expectations of a model that considers the possibility of η′−ηc(2S) mixing. The ratio of the ψ(2S)→γη′ and ψ(2S)→γη rates is used to determine the pseudoscalar octet-singlet mixing angle.Received 5 February 1998DOI:https://doi.org/10.1103/PhysRevD.58.097101©1998 American Physical …