Dresden 2017 – wissenschaftliches Programm
CPP 54.3: Vortrag
Donnerstag, 23. März 2017, 10:15–10:30, HÜL 186
Effect of the orientational relaxation on the collective motion of patterns formed by self-propelled particles. — •Alexander Chervanyov1, Hector Gomez2, and Uwe Thiele1 — 1Institut für Theoretische Physik, WWU Münster, Germany — 2Universidade da Coruna, A Coruna, Spain
We investigate the collective behavior of self-propelled particles (SPPs) undergoing competitive processes of pattern formation and rotational relaxation of their self-propulsion velocities. As a main result of this study, we quantitatively explain  transitions between different steady states of the SPPs caused by the intricate interplay among the involved effects of pattern formation, orientational order, and coupling between the SPP density and orientation fields. Based on rigorous analytical and numerical calculations, we prove that the rate of the orientational relaxation of the SPP velocity field is the main factor determining the steady states of the SPP system. Further, we determine the exact boundaries between domains in the parameter plane that delineate qualitatively different resting and moving states. In addition, we analytically calculate the collective velocity of the SPPs and show that it perfectly agrees with our numerical results. Our results can be effectively used to identify the regimes of collective behavior of SPPs in living systems in relevance to the domains of dominance of the above described effects of the self-propulsion, pattern formation and orientational relaxation of SPPs.
 A.I. Chervanyov, H. Gomez, U. Thiele, EPL 115, 68001 (2016).