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Eta Fragmentation Functions Revisited

Aidala, Christine A.·Loomis, Devon A.·Martinez, Ramiro Tomas·Sassot, Rodolfo·Stratmann, Marco
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Abstract

We revisit the extraction of parton-to-eta meson fragmentation functions at next-to-leading order accuracy in QCD in the light of the recent hadroproduction measurements in proton-proton collisions obtained by the PHENIX, LHCb, and ALICE collaborations. In addition to an increased precision, the data explore complementary rapidity ranges and center-of-mass system energies. The analysis exploits the theoretical scale dependence to ease tensions among the data sets at different energies that are potentially caused by QCD corrections beyond the next-to-leading order. The resulting set of fragmentation functions yields a consistent description of all available data. Estimates of uncertainties are obtained with the Monte Carlo replica method.

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Aidala, Christine A., Loomis, Devon A., Martinez, Ramiro Tomas, Sassot, Rodolfo, Stratmann, Marco. 2026-01-01. Eta Fragmentation Functions Revisited. https://doi.org/10.48550/arxiv.2507.04887

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