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arXiv · 1710.03529

Towards extracting the timelike pion form factor on CLS two-flavour ensembles

Felix Erben·Jeremy Green·Daniel Mohler·Hartmut Wittig
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Abstract

Results are presented from an ongoing study of the $\rho$ resonance. The focus is on CLS 2-flavour ensembles generated using $\mathcal{O}(a)$ improved Wilson fermions with pion masses ranging from $265$ to $437$ $\mathrm{MeV}$. The energy levels are extracted by solving the GEVP of correlator matrices, created with the distillation approach involving $\rho$ and $\pi\pi$ interpolators. The study is done in the centre-of-mass frame and several moving frames. One aim of this work is to extract the timelike pion form factor after applying the L\"uscher formalism. We therefore plan to integrate this study with the existing Mainz programme for the calculation of the hadronic vacuum polarization contribution to the muon $g-2$.

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Felix Erben, Jeremy Green, Daniel Mohler, Hartmut Wittig. 2017-10-10. Towards extracting the timelike pion form factor on CLS two-flavour ensembles. https://doi.org/10.1051/epjconf/201817505027

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