caa a22 4500 445865970 CHVBK 20180317145458.0 cr unu---uuuuu 170323e20110801xx s 000 0 eng 10.1140/epjd/e2011-20132-2 doi (NATIONALLICENCE)springer-10.1140/epjd/e2011-20132-2 Simeoni Jr. W. CEA, CEA-Saclay IRFU DSM, Bat. 122, 91191, Gif-sur-Yvette Cedex, France aut Process dynamics and thermodynamics of charged particle beams which remain equipartitioned [Elektronische Daten] [W. Simeoni Jr.] This paper examines the process dynamics and thermodynamics of charged particle beams which remain equipartitioned. Considering a high-intensity ion beam in a space-charge dominated regime and with an initially large mismatched RMS beam size, we observe a fast increasing spatial anisotropy of the beam. Since space-charge interactions in a high-intensity linear accelerator can lead to energy equipartition between the degrees of freedom, this anisotropization phenomena suggest a kind of route to equipartition. In this paper we show that the particle-particle resonances and mode-particle resonances lead to the anisotropization of the beam, that is, both the envelope ratio and the emittance ratio are different from one. We propose that this anisotropy is responsible for the beam's equipartitioning. The results suggest that the beam remains equipartitioned when it exhibits a macroscopic anisotropy, which is characterized by the following properties: the development of an elliptical shape with increasing size along a direction, the presence of a coupling between transversal emittances, halo formation along a preferential direction, stationarity of the temperature and a growth of the entropy in the cascade form. We call the state characterized by these properties as an anisotropic equipartition state. EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg, 2011 The European Physical Journal D Springer-Verlag 63/3(2011-08-01), 407-419 1434-6060 63:3<407 2011 63 10053 https://doi.org/10.1140/epjd/e2011-20132-2 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1140/epjd/e2011-20132-2 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Simeoni Jr W. CEA, CEA-Saclay IRFU DSM, Bat. 122, 91191, Gif-sur-Yvette Cedex, France aut NATIONALLICENCE 773 0- The European Physical Journal D Springer-Verlag 63/3(2011-08-01), 407-419 1434-6060 63:3<407 2011 63 10053 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer