This title appears in the Scientific Report :
2022
Please use the identifier:
http://dx.doi.org/10.1140/epjc/s10052-022-10247-7 in citations.
Please use the identifier: http://hdl.handle.net/2128/31228 in citations.
A dispersive analysis of ${\eta '\rightarrow \pi ^+\pi ^-\gamma }$ and ${\eta '\rightarrow \ell ^+\ell ^-\gamma }$
A dispersive analysis of ${\eta '\rightarrow \pi ^+\pi ^-\gamma }$ and ${\eta '\rightarrow \ell ^+\ell ^-\gamma }$
We present a dispersive representation of the η′ transition form factor that allows one to account, in a consistent way, for the effects of ρ–ω mixing in both the isoscalar and the isovector contributions. Using this formalism, we analyze recent data on η′→π+π−γ to constrain the isovector part of th...
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Personal Name(s): | Holz, Simon (Corresponding author) |
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Hanhart, Christoph / Hoferichter, Martin / Kubis, Bastian | |
Contributing Institute: |
Theorie der Starken Wechselwirkung; IAS-4 Theorie der starken Wechselwirkung; IKP-3 |
Published in: | The European physical journal / C, 82 (2022) 5, S. 434 |
Imprint: |
Heidelberg
Springer
2022
|
DOI: |
10.1140/epjc/s10052-022-10247-7 |
Document Type: |
Journal Article |
Research Program: |
TRR 110: Symmetrien und Strukturbildung in der Quantenchromodynamik Domain-Specific Simulation & Data Life Cycle Labs (SDLs) and Research Groups |
Link: |
OpenAccess |
Publikationsportal JuSER |
Please use the identifier: http://hdl.handle.net/2128/31228 in citations.
We present a dispersive representation of the η′ transition form factor that allows one to account, in a consistent way, for the effects of ρ–ω mixing in both the isoscalar and the isovector contributions. Using this formalism, we analyze recent data on η′→π+π−γ to constrain the isovector part of the form factor, individually and in combination with data for the pion vector form factor, which suggests a tension in the ρ–ω mixing parameter. As a first application, we use our results, in combination with the most recent input for the isoscalar part of the form factor, to predict the corresponding spectrum of η′→ℓ+ℓ−γ, in particular we find the slope parameter bη′=1.455(24)GeV−2. With forthcoming data on the latter process, our results establish the necessary framework to improve the evaluation of the η′-pole contribution to the anomalous magnetic moment of the muon using experimental input from both η′ decay channels. |