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v-USPhydro known as  viscous Ultrarelativistic Smoothed Particle hydrodynamics is an 2+1 event-by-event viscous relativistic hydrodynamical model that solves Israel-Stewart equations for both bulk and shear viscosities.  v-USPhydro was originally created at the University of Sao Paulo by Jacquelyn Noronha-Hostler, Gabriel Denicol, Jorge Noronha, Rone P. G. Andrade, and Frederique Grassi.  


There are two methods to solve hydrodynamical equations: the Eulerian method (grid) and the Lagrangian method (mesh free).  The Eulerian method uses a predetermined grid and observes the fluid flowing pasts those points whereas the Lagrangian method discretizes the fluid into separate "particles" and observes their velocity and position over time.  In v-USPhydro we use the well-known Lagrangian method called Smoothed Particle Hydrodynamics (SPH),  which provides a framework for quickly solving the Equations of Motion. 


The Smoothed Particled Hydrodynamics was originally created in the field of astrophysics but has since been applied to many other fields.  The first to use it in the field of Heavy Ions was the NeXSPHeRIO code (based on inviscid hydrodynamics) established in a joint collaboration between the University of Sao Paulo and the Federal University of Rio de Janeiro.  Other uses of SPH: Astrophysics, Geology, Ballistics, Video Gaming.


Initial work using v-USPhydro has found that there is a non-trivial compensating effect between the bulk and shear viscosity. A larger than initially expected shear viscosity may be possible as long as a non-zero bulk viscosity is considered. Further work with v-USPhydro can be found below.  


v-USPhydro can handle a variety of initial conditions and a non-zero intial flow.  Hadronic interactions are taken into account with the UrQMD transport code.  At the moment, v-USPhydro is not an open source code, but eventually the hope is to make it publically available.  



v-USPhydro Publiations:


  • Giacalone, Yan, Noronha-Hostler, Ollitrault, arXiv:1608.06022 

  • Gardim, Grassi, Luzum, Noronha-Hostler, arXiv:1608.02982

  • Giacalone, Yan, Noronha-Hostler, Ollitrault,  arXiv:1608.01823

  • J. Noronha-Hostler,  J.Phys.Conf.Ser. 736 (2016) no.1, 012019 

  • G. Giacalone, L. Yan, J. Noronha-Hostler and J. Y. Ollitrault,   Phys.Rev. C94 (2016) no.1, 014906

  • J. Noronha-Hostler, B. Betz, J. Noronha and M. Gyulassy,   Phys.Rev.Lett. 116 (2016) no.25, 252301 

  • J. Noronha-Hostler, J. Noronha and M. Gyulassy, Accepted in Nucl. Phys. A, arXiv:1512.07135 [nucl-th].

  • J. Noronha-Hostler, Proceedings of CIPANP2015, eConf, arXiv:1512.06315 [nucl-th].

  • J. Noronha-Hostler, M. Luzum and J. Y. Ollitrault, Phys.Rev. C93 (2016) no.3, 034912 

  • J. Noronha-Hostler, L. Yan, F. G. Gardim and J. Y. Ollitrault, Phys. Rev.
    C 93, no. 1, 014909 (2016).

  • J. Noronha-Hostler, J. Noronha, M. Gyulassy, Phys.Rev. C93 (2016) no.2, 024909 

  • F. G. Gardim, J. Noronha-Hostler, M. Luzum and F. Grassi, Phys.Rev. C91 (2015) 3, 034902.

  • J. Noronha-Hostler, J. Noronha and F. Grassi, Phys. Rev. C 90,

    034907 (2014).

  • J. Noronha-Hostler, G. S. Denicol, J. Noronha, R. P. G. Andrade

    and F. Grassi, Phys. Rev. C 88, 044916 (2013).

  • J. Noronha-Hostler, G. S. Denicol, J. Noronha, R. P. G. Andrade and F. Grassi, J.Phys.Conf.Ser. 458 (2013) 012018.

  • J. Noronha-Hostler, J. Noronha, G. S. Denicol, R. P. G. Andrade, F. Grassi

    and C. Greiner,Phys. Rev. C 89, 054904 (2014).



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