Related Experiment Videos
Percolation effects in very-high-energy cosmic rays.
J Dias de Deus1, M C Espírito Santo, M Pimenta
1CENTRA, LIP, and IST, Avenida Rovisco Pais, 1049-001 Lisboa, Portugal. jdd@fisica.ist.utl.pt
Physical Review Letters
|May 23, 2006
Summary
Percolation effects in cosmic ray showers explain discrepancies between experimental data and theoretical models. This approach suggests deeper shower development at high energies, resolving puzzles in cosmic ray physics.
Area of Science:
- Astroparticle Physics
- High-Energy Cosmic Rays
- Particle Shower Development
Background:
- Discrepancies exist between ground array and fluorescence detector data for cosmic rays at approximately 10^20 eV.
- A change in the shower maximum depth (Xmax) slope around 10^17 eV suggests a primary composition change.
Purpose of the Study:
- To propose a unified model for high-energy cosmic ray phenomena.
- To explain observed discrepancies and Xmax behavior without invoking composition changes.
Main Methods:
- Incorporating percolation effects into cosmic ray shower development models.
- Analyzing the impact of percolation on inelasticity (K) at high energies.
Main Results:
- Percolation effects naturally explain deeper shower development at energies above approximately 10^17 eV.
- This model accounts for both the high-energy data discrepancy and the observed Xmax energy dependence.
Conclusions:
- Percolation provides a viable alternative to composition change for explaining cosmic ray anomalies.
- The model offers a consistent framework for understanding shower development across a wide energy range.