Effective temperature of active matter.

@article{Loi2008EffectiveTO,
  title={Effective temperature of active matter.},
  author={Davide Loi and Stefano Mossa and Leticia F. Cugliandolo},
  journal={Physical review. E, Statistical, nonlinear, and soft matter physics},
  year={2008},
  volume={77 5 Pt 1},
  pages={
          051111
        }
}
We follow the dynamics of an ensemble of interacting self-propelled motorized particles in contact with an equilibrated thermal bath. We find that the fluctuation-dissipation relation allows for the definition of an effective temperature that is compatible with the results obtained using a tracer particle as a thermometer. The effective temperature takes a value which is higher than the temperature of the bath, and it is continuously controlled by the motor intensity. 

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