Measurement of antiproton production from antihyperon decays in pHe collisions at $\sqrt{s_{NN}}=110$ GeV

TL;DR

This paper measures the contribution of antihyperon decays to antiproton production in proton-helium collisions at high energy, providing crucial data to improve cosmic ray antiproton flux models.

Contribution

It provides the first direct measurement of antihyperon decay contributions to antiproton production at LHC energies, highlighting discrepancies with existing models.

Findings

Antihyperon contributions are larger than model predictions.

Exclusive measurement of $ar{ ext{Lambda}}$ decay contribution.

Enhanced understanding of antiproton sources in cosmic rays.

Abstract

The interpretation of cosmic antiproton flux measurements from space-borne experiments is currently limited by the knowledge of the antiproton production cross-section in collisions between primary cosmic rays and the interstellar medium. Using collisions of protons with an energy of 6.5 TeV incident on helium nuclei at rest in the proximity of the interaction region of the LHCb experiment, the ratio of antiprotons originating from antihyperon decays to prompt production is measured for antiproton momenta between 12 and 110 GeV/c. The dominant antihyperon contribution, namely $\bar{\Lambda} \to \bar{p} \pi^+$ decays from promptly produced $\bar{\Lambda}$ particles, is also exclusively measured. The results complement the measurement of prompt antiproton production obtained from the same data sample. At the energy scale of this measurement, the antihyperon contributions to antiproton production are observed to be significantly larger than predictions of commonly used hadronic production models.