UCLA graduate student Peicheng Yu, current PICKSC post-doc Xinlu Xu, and collaborators have been investigating the mitigation of the numerical Cerenkov instability (NCI) which occurs when a plasma drifts near the speed of light in a PIC code. In a series of papers (references below) they have developed a general theory as well as mitigation strategies for fully spectral (FFT based) and hybrid (FFT and finite difference) solvers. Recently they published an article in Communications in Computer Physics [1] and posted a new article on the arxiv: arXiv:1502.01376 [physics.comp-ph]. If you would like more information, please contact Mr. Peicheng Yu at tpc02@ucla.edu.

Expand for References:

**192**, 32 (2015). doi link

2. P. Yu, X. Xu, V. K. Decyk, W. An, J. Vieira, F. S. Tsung, R. A. Fonseca, W. Lu, L. O. Silva, W. B. Mori, “Modeling of laser wakefield acceleration in Lorentz boosted frame using EM-PIC code with spectral solver.” JOURNAL OF COMPUTATIONAL PHYSICS

**266**, 124 (2014). doi link

3. X. Xu, P. Yu, S. F. Martins, F. S. Tsung, V. K. Decyk, J. Vieira, R. A. Fonseca, W. Lu, L. O. Silva, W. B. Mori, “Numerical instability due to relativistic plasma drift in EM-PIC simulations.” COMPUTER PHYSICS COMMUNICATIONS

**184**, 2503 (2013). doi link

4. P. Yu, et al., in Proc. 16th Advanced Accelerator Concepts Workshop, San Jose, California, 2014.

5. P. Yu, X. Xu, V. K. Decyk, S. F. Martins, F. S. Tsung, J. Vieira, R. A. Fonseca, W. Lu, L. O. Silva, and W. B. Mori, “Modeling of laser wakefield acceleration in the Lorentz boosted frame using OSIRIS and UPIC framework,” AIP Conf. Proc.

**1507**, 416 (2012). doi link