Journal Article

FZJ-2021-04254

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Towards an improved understanding of ${\eta \rightarrow \gamma ^*\gamma ^*}$

Holz, S. ; Plenter, J. ; Xiao, C. W. ; Dato, T. ; Hanhart, C.FZJ* ; Kubis, B. (Corresponding author) ; Meißner, U.-G.FZJ* ; Wirzba, A.FZJ*

2021
Springer Heidelberg

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Please use a persistent id in citations: http://hdl.handle.net/2128/29077  doi:10.1140/epjc/s10052-021-09661-0

Abstract: We argue that high-quality data on the reaction e+e−→π+π−η will allow one to determine the doubly-virtual form factor η→γ∗γ∗ in a model-independent way with controlled accuracy. This is an important step towards a reliable evaluation of the hadronic light-by-light scattering contribution to the anomalous magnetic moment of the muon. When analyzing the existing data for e+e−→π+π−η for total energies squared k2>1GeV2, we demonstrate that the effect of the a2 meson provides a natural breaking mechanism for the commonly employed factorization ansatz in the doubly-virtual form factor Fηγ∗γ∗(q2,k2). However, better data are needed to draw firm conclusions.

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Contributing Institute(s):

1. Theorie der Starken Wechselwirkung (IAS-4)
2. Theorie der starken Wechselwirkung (IKP-3)

Research Program(s):

1. 5111 - Domain-Specific Simulation Data Life Cycle Labs (SDLs) and Research Groups (POF4-511) (POF4-511)
2. DFG project 196253076 - TRR 110: Symmetrien und Strukturbildung in der Quantenchromodynamik (196253076) (196253076)

Appears in the scientific report 2021

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Database coverage:
; ; ; ; ; Clarivate Analytics Master Journal List ; Current Contents - Physical, Chemical and Earth Sciences ; DOAJ Seal ; Ebsco Academic Search ; Essential Science Indicators ; IF < 5 ; JCR ; Nationallizenz ; SCOAP3 sponsored Journal ; SCOPUS ; Science Citation Index Expanded ; Web of Science Core Collection

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