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Published on: November 15, 2013
Time-dependent properties of a simplified Fermi-Ulam accelerator model
Denis Gouvêa Ladeira1, Jafferson Kamphorst Leal da Silva
1Departamento de Física, ICEx Universidade Federal de Minas Gerais Caixa Postal 702, 30.123-970, Belo Horizonte/MG, Brazil. dgl@fisica.ufmg.br
Summary
Numerical simulations of a simplified Fermi-Ulam accelerator reveal that average energy and collisions scale with small oscillation amplitudes. After initial rise, average energy peaks and then slowly decays over time.
Area of Science:
- Physics
- Dynamical Systems
- Statistical Mechanics
Background:
- The Fermi-Ula m accelerator model explores energy transfer in a system with a moving boundary.
- Understanding chaotic dynamics in low-energy regimes is crucial for various physical phenomena.
Purpose of the Study:
- To numerically investigate the chaotic low-energy region of a simplified Fermi-Ulam accelerator.
- To determine the time-dependent behavior of average energy and number of collisions.
Main Methods:
- Numerical simulations were employed to model the system dynamics.
- Analysis focused on the scaling properties of average energy and collision count.
Main Results:
- Average energy and number of collisions exhibit clear scaling behavior for small oscillation amplitudes of the moving wall.
- A transient regime is observed, followed by an increase in average energy.
- The average energy reaches a maximum before exhibiting an unexpected slow decay.
Conclusions:
- The simplified Fermi-Ulam accelerator displays complex dynamics, including scaling and a non-monotonic energy evolution.
- The observed slow decay of average energy warrants further investigation into the underlying mechanisms.
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