Antiproton annihilation at rest in thin solid targets and comparison with Monte Carlo simulations

Area of Science:

• Nuclear Physics
• Particle Physics
• Hadron Physics

Background:

• The mechanism of antiproton-nucleus annihilation at rest is a complex phenomenon with ongoing theoretical and experimental investigations.
• Despite extensive research, a complete understanding of the annihilation process and its resulting particle production is still lacking.

Purpose of the Study:

• To experimentally investigate antiproton-nucleus annihilation at rest by measuring charged particle multiplicities and energy deposits.
• To compare experimental results with predictions from established simulation tools (Geant4, FLUKA) and various theoretical models.

Main Methods:

• Utilized slow extracted antiprotons from the ASACUSA apparatus at CERN.
• Conducted experiments involving antiproton annihilation at rest on carbon, molybdenum, and gold targets.
• Measured charged particle multiplicities and their energy deposits.

Main Results:

• Collected detailed data on charged particle production and energy deposition for antiproton annihilations on different nuclei.
• Observed discrepancies between experimental data and predictions from current simulation models.
• Identified specific features of the annihilation process not adequately reproduced by existing models.

Conclusions:

• Current theoretical models and simulation tools do not fully account for the observed features of antiproton-nucleus annihilation at rest.
• Further experimental measurements, particularly at low energies, are crucial for validating and refining theoretical models.
• The study highlights the need for improved models to accurately describe antiproton-nucleus interactions.