
Title
Research Staff 
Email
xu2@llnl.gov 
Phone
(925) 4237578 
Organization
PLSPHYSPHYSICS
Research Experience
 Staff Physicist, LLNL, 1996–Present
 Postdoctoral, LLNL, 1993–1996
Xueqiao Xu is a theoretical and computational plasma physicist, specialized in boundary plasma physics, largescale computing, and Artificial Intelligent / Machine Learning. He is a Fellow of the American Physical Society, and has published about 168 publications and 26 conference proceedings in theoretical, computational and experimental plasma physics, with a total citation of 8217, an hindex of 44, and an i10index of 117 (Google Scholar). He is coauthor of 2014 Nuclear Fusion Prize paper with Phil Snyder. He is the original developer of the BOUT code and codeveloper of the BOUT++ code, jointly with University of York and with extensive experience of mentoring 27 PhD students, 22 postdocs and junior staff. He leads an international collaboration for ongoing development of the BOUT++ code on pedestal and the SOL physics, ELMs, edge turbulence, and divertor heat flux simulations with collaborative groups from the U.S., U.K., China, South Korea, and Japan.
Achievements
 Coinvented new Monte Carlo scheme for usual gyrokinetic δf particleincell plasma microturbulence simulations for modeling Coulomb collisions
 Developed the BOUT twofluid edge turbulence code
 Lead physics developer for 5D continuum edge gyrokinetic code TEMPEST
 Codeveloped the BOUT++ twofluid edge turbulence code
Postdoctoral, University of California, Berkeley, 1990–1993
Ph.D., Plasma Physics, University of Texas at Austin, 1990
M.A., Plasma Physics, Institute of Plasma Physics, Academia Sinica, Hefei  Anhui, China, 1985
Dr. Xu has over 150 refereed publications.
Chenhao Ma , Ben Zhu , XueQiao Xu , and Weixing Wang, Machine learning surrogate models for Landau fluid closure, Phys. Plasmas 27, 042502 (2020).
X.Q. Xu, N.M. Li, Z.Y. Li, B. Chen, T.Y. Xia, T.F. Tang, B. Zhu, and V.S. Chan, Simulations of tokamak boundary plasma turbulence transport in setting the divertor heat flux width, Nucl. Fusion 59 (2019).
X. Q. Xu, T. Y. Xia, N. Yan, Z. X. Liu, D. F. Kong, A. Diallo, R. J. Groebner, A. E. Hubbard and J. W. Hughes, Toward integrated multiscale pedestal simulations including edgelocalizedmode dynamics, evolution of edgelocalizedmode cycles, and continuous fluctuations, Physics of Plasmas 23, 055901 (2016).
X. Q. Xu, J. F. Ma, G. Q. Li, Impact of the pedestal plasma density on dynamics of edge localized mode crashes and energy loss scaling, Phys. Plasmas 21, 120704 (2014).
P. W. Xi, P. W. Xi, X. Q. Xu, P.H. Diamond, Phase Dynamics Criterion for Fast Relaxation of HighConfinementMode Plasmas, Phys. Rev. Lett. 112, 085001 (2014).
X. Q. Xu, P. W. Xi, A. Dimits, I. Joseph, M. V. Umansky et al., Gyrofluid and twofluid theory and simulations of edgelocalizedmodes, Physics of Plasmas 20, 056113 (2013).
X.Q. Xu, B. Dudson, P.B. Snyder, M.V. Umansky, and H. Wilson, Nonlinear Simulations of PeelingBallooning Modes with Anomalous Electron Viscosity and their Role in Edge Localized Mode Crashes, Physical Review Letters, Vol. 105, 175005.
B. D. Dudson, M. V. Umansky, X. Q. Xu, P. B. Snyder, and H. R. Wilson, BOUT++: a framework for parallel plasma fluid simulations, Computer Physics Communications, Vol. 180, 1467 (2009).
X.Q. Xu, E. Belli, K. Bodi, et al., Dynamics of kinetic geodesicacoustic modes and the radial electric field in tokamak neoclassical plasmas, NUCLEAR FUSION, VOL. 49, 065023 (2009).
X. Q. Xu, Z. Xiong, Z. Gao, W. M. Nevins, and G. R. McKee. "TEMPEST Simulations of Collisionless Damping of the GeodesicAcoustic Mode", Phys. Rev. Lett., 100, (2008).
X. Q. Xu, M. V. Umansky, B. Dudson, and P. B. Snyder. "Boundary Plasma Turbulence Simulations for Tokamaks", Communication in Computational Physics, 4 (2008) 949979.
X. Q. Xu "Neoclassical Simulation of Tokamak Plasmas using Continuum", Phys. Rev. E, V.78, 016406 (2008).
Z. Xiong, R.H. Cohen,T.D. Rognlien, X.Q. Xu. "A HighOrder FiniteVolume Algorithm for FokkerPlanck Collisions in Magnetized Plasmas", J. Comput. Phys., V. 227, (2008) 71927205.
Umansky, MV; Cohen, RH; LoDestro, LL; Xu, XQ. "Suite of verification test problems for edge turbulence simulations", Contrib. Plasma. Phys., 48, 2731, (2008).
Cohen, RH; Xu, XQ. "Progress in kinetic simulation of edge plasmas", Contrib. Plasm. Phys., 48, 212223, (2008).
X. Q. Xu; Xiong, Z; Dorr, MR; Hittinger, JA, et al., "Edge gyrokinetic theory and continuum simulations", Nucl. Fusion, 47, 809816, (2007).
Qin, H; Cohen, RH; Nevins, WM; Xu, XQ. "Geometric gyrokinetic theory for edge plasmas", Phys. Plasmas, 14, (2007).
X. Q. Xu, R.H.Cohen, T.D.ROGNLIEN, and J.R.Myra, LH transitions simulations in Divertor Geometry, Physics of Plasma, Vol. 7, no. 5 19511958 (2000).
X. Q. Xu, M. N. Rosenbluth, Numerical simulation of iontemperaturegradientdriven modes, Phys. Fluids, B 3, 627643 (1991).
Full Publications record can be found the website: https://bout.llnl.gov/publications