27–28 Jun 2024
Centro de Estudos Avanzados
Europe/Zurich timezone

Proton-air interactions at ultra-high energies in muon-depleted air showers with different depths

27 Jun 2024, 09:40
20m
Centro de Estudos Avanzados

Centro de Estudos Avanzados

Santiago de Compostela Parque de Vista Alegre. Rúa das Salvadas, s/n 15782 https://www.usc.gal/gl/edificio/centro-estudos-avanzados

Speaker

Miguel Martins

Description

The hardness of the energy spectrum of neutral pions produced in proton-air interactions at ultra-high energies, above $10^{18}$ eV, is constrained by the steepness of the distribution of the number of muons in muon-depleted extensive air showers.

In this work, we find that this steepness, quantified by the parameter $\Lambda_{\mu}$, evolves with the depth of the shower maximum, $X_{\max}$, assuming a universal value for shallow showers and an enhanced dependence on the high-energy hadronic interaction model for deep showers. We show that $X_{\max}$ probes the so-called hadronic activity of the first interaction, thus allowing direct access to the energy spectrum of neutral pions in different regions of the kinematic phase space of the first interaction.

We verify that the unbiased measurement of $\Lambda_{\mu}$ is possible for realistic mass composition expectations. Finally, we infer that the statistical precision in $\Lambda_{\mu}$ required to distinguish between hadronic interaction models can be achieved in current extensive air shower detectors, given their resolution and exposure.

Author

Miguel Martins

Co-authors

Lorenzo Cazon (IGFAE-USC) Ruben Conceição (LIP) felix riehn (LIP Lisbon)

Presentation materials

There are no materials yet.