[phys4phys] Reminder: PSL laboratory seminar - Blagoje Djordjevic (LLNL) Monday 07.11.2022.

[Ivan Traparić]

Dear colleagues,

You are cordially invited to the Plasma Spectroscopy and Lasers 
laboratory seminar,
which will be held in the library reading room "Dr. Dragan Popović"
on Monday, 7th November 2022 at 12:00.

The talk entitled

"Transfer learning and multi-fidelity modeling of laser-driven particle
acceleration"

will be given by Dr. Blagoje Djordjevic (Lawrence Livermore National 
Laboratory)

Abstract of the talk:
Computer models of intense, laser-driven ion acceleration require 
expensive particle-in-cell (PIC)
simulations that may struggle to capture all the 
multi-scale,multi-dimensional physics involved at
reasonable costs. Explored is an approach to ameliorate this deficiency 
using a multi-fidelity model that
can incorporate physical trends and phenomena at different levels. As 
the base framework for this study,
an ensemble of approximately 10,000 1D PIC simulations was generated to 
buttress separate ensembles
of hundreds of higher fidelity 1D and 2D simulations. Using transfer 
learning with deep neural networks,
one can reproduce the results of more complex physics at a much smaller 
cost. The networks trained in
this fashion can in turn act as surrogate models for the simulations 
themselves, allowing for quick and
efficient exploration of the parameter space of interest. Standard 
figures-of-merit were used as
benchmarks such as the hot electron temperature, peak ion energy, 
conversion efficiency, etc. These
surrogate models are also useful for incorporating more complex schemes, 
such as pulse shaping. We can
rapidly identify and explore under what conditions dimensionality 
becomes an important effect and
search for outliers in feature space.



-- 
Ivan Traparić
Laboratory for Plasma Spectroscopy and Lasers
Institute of Physics Belgrade
Pregrevica 118, Zemun, 11080
http://psl-lab.ipb.ac.rs/
http://www.ipb.ac.rs/