Precise QCD Predictions for Hadron-in-jet Production in $e^+e^-$ Collisions

Abstract

The production of identified hadrons inside jets in $e^+ e^-$ annihilation allows for detailed studies of parton-to-hadron fragmentation functions in a clean environment. We compute hadron-in-jets production cross sections for $e^+e^- \to 2\,\mathrm{jets}$ and $e^+e^- \to 3\,\mathrm{jets}$ to next-to-next-to-leading order (NNLO) in perturbative QCD. By comparing with data from the ALEPH experiment, we demonstrate the implications of the newly computed theory predictions for precision phenomenology.

Figures (5)

• Figure 1: Data--theory comparison for $\pi^0$ production in 2-jet exclusive events up NNLO with BDSSV22FF_NNLO_PI0. Left panel: $\mu_a = \sqrt{s}$. Right panel: $\mu_a = \sqrt{y_\mathrm{cut} s}$.
• Figure 2: Data--theory comparison of $\pi^0$ production in 2-jet exclusive events at NNLO with different FF sets.
• Figure 3: Data--theory comparison for $\eta$ production in 2-jet exclusive events up NNLO for ALMSS25_ETA_nlo (green) and NPC23_Eta_nlo (purple) FF sets. Left panel: NLO. Right panel: NNLO.
• Figure 4: Data--theory comparison for $\pi^0$ production in 3-jet exclusive events up NNLO with BDSSV22FF_NNLO_PI0. Left panel: $\mu_a = E_{j(H)}$. Right panel: $\mu_a = \sqrt{y_\mathrm{cut} s}$.
• Figure 5: Data--theory comparison of $\pi^0$ production in 3-jet exclusive events at NNLO with different FF sets.