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Ivan became Research Assistant

We proudly announce that since 7th November 2022., Ivan has a new scientific title of Research Assistant at the Insitute of Physics Belgrade. We wish him a lot of success in his research in the years to come.

Ivan took part in this year ITER International School held in Aix – en – Provence

It is our great pleasure to report that Ivan was accepted to participate in this year ITER International School 2023. The topic of the summer school was Energetic Particles in Fusion Plasmas, where the school gathered leading experts in this filed that gave lectures to the students. Part of the summer school was also dedicated to the visit of ITER site, where students had the opportunity to see the site and to hear recent advances in the construction of the largest tokamak so far.

Ivan presented part of his PhD thesis work on 14th SCSLSA

14th SCSLSA was held in Bajna Bašta from 19th to 23rd June. Ivan was invited to give a progress report on his wok on application of Machine Learning algorithms on the determination of Stark Broadening line widths. The talk was entitled Stark Broadening Modeling with ML and AI Algorithms and abstract is given below.

During past 20 years many Stark broadening models were developed that can calculate spectral lineshape and estimate a line width that is extensively used in plasma diagnostics of both astrophysical and laboratory plasmas. Some of these calculations yield results relatively fast, some of them need a lot of computational time. Therefore, idea of creating a machine learning (ML) model emerged as a tool for fast estimation of Stark width without need of huge computational time. In our approach, out of three tested models, random forest (RF) algorithm showed the best predictive power after it has been trained, where the coefficient of determination R2 = 0.94 was obtained. Model was trained on a database created by merging parameters from Stark B and NIST atomic databases, it had 14 input parameters that were used to predict final Stark width. Results were compared with experimental ones as well as with SCP theory. We also checked for regularities in Stark effect, and they were also confirmed and in agreement with previous findings.

Ivan took part in scientific excursion organised by Faculty of Physics

From 29th May until 3rd June Ivan took part in scientific excursion jointly organised by Faculty of Physics of University of Belgrade and Physical Society of Serbia. Firstly they visited Electrotechnical Faculty of University of Brno, where they saw Laboratory for High Voltages and High Currents.

Next they visited Institute of Plasma Physics of Czech Academy of Sciences and Arts where they had a lecture given by prof. Jan Horacek from IPP about fusion and tokamak physics in general. This was followed by the tour through PALS laboratory, where they saw a PW iodine laser system.

The next day they went to Dresden, to visit Helmholtz Zentrum Dresden – Rossendorf scientific institute, where they had opportunity to see free – electron laser system located at ELBE facility, as well as PW laser system DRACO that was recently put in operation.

At the end, they were guests in ELI beams facility, where they saw the most powerful laser systems in the world and had pleasure of hearing interesting lectures from experts employed there.

Nenad published new article

We are pleased to announce that Neša, together with his collaborators, has published new article entitled The significance of applying different factors for the evaluation of sediment contamination by toxic elements and estimation of the ecological risk in Environmental Science and Pollution Research.

Ivan’s new publication

We are pleased to announce that Ivan, together with Ivke has published the article entitled Determination of austenitic steel alloys composition using laser-induced breakdown spectroscopy (LIBS) and machine learning algorithms in European Physical Journal D (EPJ D).

Lecture by Biljana at Astronomical Observatory of Belgrade

In collaboration with Faculty of Dramatic Arts of University of Belgrade, through project CORIOUS, Biljana held a lecture called “Beriilium” at  Astronomical Observatory of Belgrade. This was a lecture with aim to promote science and to explain at first glance complicated scientific concepts and results to general public with original scenography and special effect, created by her colleagues from FDA. The official abstract of this lecture was:

Our Augmented Lecture goes high above us into the cosmos, among the stars, using the chemical element called Beryllium. Through it, Dr Biljana Stankov, a research associate at the Institute of Physics in the laboratory for Plasma Spectroscopy and Lasers, and Milica Stojšić, an architect and artist in the field of light design, meet on stage. Inspired by the doctoral research of the scientist Biljana Stankov, we came to the central question posed by this lecture: is it possible to put the glow of the stars, which we see at night, on our palm and look at it up close? And is it possible to create it? Our lecture will try to “catch” the completely elusive, to clearly “see” what is invisible to the naked eye and to infiltrate into the incredibly complex nature of light, thanks to which we see the whole world around us, and which we cannot perceive and understand independently. In the exceptional ambience of the Observatory on Zvezdara, which is intended for closer acquaintance and observation of the cosmos, we will try to create our own little cosmos on stage, in which the audience will get closer to and shed light on this incredible branch of science, at this exciting, joint site-specific lecture.

Lecture by Dr Blagoje Đorđević (Lawrence Livermore National Laboratory)

It is our great pleasure to inform you, that today our guest Dr Blagoje Đorđević from Lawrence Livermore National Laboratory held a lecture entitled “Transfer learning and multi-fidelity modeling of laser-driven particle acceleration” at library reading room “Dr. Dragan Popović”. The abstract of the talk was:

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 participated at SLSP6

Ivan took participation at 6th Spectral Line Shapes in Plasma Workshop (SLSP6) where he held 15 minute lecture entitled Stark Broadening Modeling with ML Algorithms, in which he presented his recent work on application of machine learning algorithms for modeling of Stark spectral line broadening.

Milica defended her PhD thesis

We are proud to announce that Milica defended her PhD Thesis entitled “Primena spektroskopije laserski indukovane plazme za određivanje tragova metala u uljima” (“Application of Laser-Induced Breakdown Spectroscopy for the determination of trace metals in oils”) on 29nd September 2022 at the Faculty of Physical Chemistry. Thesis advisors were dr Milivoje Ivković and dr Miroslav Kuzmanović, the PhD Defense Committee president was dr Ivana Stojković Simatović while the Committee members were dr Jelena Savović and dr Miroslav Ristić.

We wish her all the best in her future work!