# Production cross sections of hyperons and charmed baryons from $e^+e^-$ annihilation near $\sqrt{s} = 10.52$~GeV

## TL;DR

This paper reports the first measurements of direct production cross sections of hyperons and charmed baryons in electron-positron collisions near 10.52 GeV, revealing exponential behavior and diquark structure indications.

## Contribution

It provides the first direct production cross sections for hyperons and charmed baryons from $e^+e^-$ annihilation near 10.52 GeV, with detailed analysis of suppression patterns and baryon structure implications.

## Key findings

- Hyperon cross sections follow an exponential distribution with a single slope.
- Suppression observed for $ ext{Σ}(1385)^+$ and $ ext{Ξ}(1530)^0$ hyperons.
- A threefold difference in $ ext{Λ}_c^+$ production suggests diquark structure.

## Abstract

We measure the inclusive production cross sections of hyperons and charmed baryons from $e^+e^-$ annihilation using a 800 fb$^{-1}$ data sample taken near the $\Upsilon(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^+ e^-$ collider. The feed-down contributions from heavy particles are subtracted using our data, and the direct production cross sections are presented for the first time. The production cross sections divided by the number of spin states for $S=-1$ hyperons follow an exponential function with a single slope parameter except for the $\Sigma(1385)^+$ resonance. Suppression for $\Sigma(1385)^+$ and $\Xi(1530)^0$ hyperons is observed. Among the production cross sections of charmed baryons, a factor of three difference for $\Lambda_c^+$ states over $\Sigma_c$ states is observed. This observation suggests a diquark structure for these baryons.