Victor BURIDON

En résumé

Entreprises

• CEA Paris-Saclay - Engineer Researcher

  Saclay (91400) 2021 - maintenant

• Cnrs - Postdoc in electronic antineutrinos detection for SoLiD experience

  Caen (14000) 2018 - 2020 Recent measurements showed a deficit between the number of electronic anti-neutrino (e-a-n) produced by reactors (short distance) and one expected. The SoLid experience was done to measure this deficit from a new technology based on the combination of 2 scintillators. The goal of this experience is to search for the origin of this difference. This could be due to an oscillation of e-a-n toward a new flavor : the sterile or an anomaly on our reactors models.
  
  A high granularity detector was put at short distance ( Planning for continuous data taking.
  -> Shift and upgrade campaigns.
  -> Calibration campaigns used for N efficiency
  
  2) Data Analysis using multi-parametric methods and Machine Learning
  The acquisition system is based on the ES-NS detection in coincidence. Among those, 2 classes embed coincident ES-NS, with similar spatial and time signature ( IBD and BiPo-214 decay). So, a high discrimination level is required to optimize the selection of IBD and the rejection of the BiPo-214.
  a) Pulse Shape Discrimination (PSD)
  -> Ratio of charge integration window
  -> Performances : IBD evt efficiency of 80% for a BiPo-214 rejection of 80%.
  b) 1D-CNN
  -> to improve the discrimination power
  -> to reduce the sensitivity to baseline variation.
  This method showed an improvement by a factor 2-3 on BiPo-214 rejection at same IBD efficiency.

• Institut Laue Langevin - Postdoc/Research Engineer in neutron detection

  Grenoble 2016 - 2018 R&D on Boron Multi-Grids gaseous detectors used for neutron detection. Boron Multi-Grid technology allows to build neutron detectors more mechanically malleable and at lower cost than He3 ones. This technology has been developed and tested at Institut Laue Langevin (ILL, Grenoble) in order to prove that it can be used for the Time Of Flight experiences, which will take place at the European Spallation Source (ESS, Sweden, Lund).
  
  1) Characterization of the technical and the operating specifications (ex : operating mode for gas flow, HV..., thermal neutrons detection efficiency, spatial resolution, maximal count rate withstood...).
  
  2) Alternance between mounting/measurement phase and data processing/data analysis phase in order to define the operating technical limits and to improve some functionalities in accordance to ESS needs.
  - To prove that this technology alternative to He3 ones can be used to build large scale detectors.
  - Tests at low pressure to demonstrate the capability to implement this technology on Time of Flight experiences.
  -Improvement of the electronic readout and development of algorithms in order to perfect the spatial resolution of the interaction point.
  - Improvement of the acquisition system to facilitate the data taking/data analysis through the creation of low size files. It allows the direct observation of the correlations between observables measured and it permits to monitor the data quality.
  

• CNRS - Postdoc in instrumentation/detection of high energy particles

  Lyon (69000) 2013 - 2015 R&D on Glass Resistive Plate Chambers (GRPCs) in order to demonstrate that this technology can be used for many and interdisciplarity fields of high energy physic. I worked in 3 different projects : ILC, GIF++ and TOMUVOL.
  
  ILC project consists of building a large scale detector (1cube meter) as a prototype of a hadronic calorimeter. This large scale detector is equipped by 50 layers of simple gap GRPCs and 1 layers of multi-gap GRPC (the farthest of the beam). Developments have been done in mechanic, electronic and programmation. Mechanical developments permit to facilitate the mounting/maintenance phases. Electronical ones permit to ensure the detection of particles (pions, muons, electrons ...) with a high efficiency (>99% at 8 kV) and with a high granularity to recognize particles from their topological shapes drawn on the several layers of the calorimeter. Developments in programmation permit to monitor the set-up and the quality of data taken.
  
  GIF++ project consists of using GRPC technology for CMS upgrades. For this, new generation of GRPCs have been built : the High Rate GRPCs. The main difference between this new generation of detector and the old one is the composition of the glass. The first step was to mount a telescope equipped by standard GRPCs and High Rate GRPCs and to put them inside a high radioactivity environment. These two generations of detectors were compared in terms of muon detection efficiency and aging. For High Rate GRPCs, developments have been done to build adaptative chambers which follow the CMS needs (strip readout electronic, petal geometry...).
  
  TOMUVOL project uses GRPCs technology to scan the internal density of volcanoes from the detection of atmospheric muons. This project consists of mounting a 1 cube meter telescope, equipped by 4 layers (with 6 GRPCs) which ensure a detection surface of ~1m² each. These layers are spaced by 180 cm, in depth direction. During the campaigns of measurement, the set-up was put at 1 km of the Puy de Dome and data were taken continuously during 6 months to get enough statistic to estimate the internal density with high precision. GRPC technology can be used for these experiences because it permits to produce large scale detectors, at low cost and with a high detection efficiency for this muon rate and the associated energy range (95-99%). The main disadvantage appears on the muon rate, responsible of the long-time measurement. Moreover, it is necessary to do many measurements at several positions arround the volcano to get a 3D image of it, if only one telescope is available and mounted. So, these long-time measurements are problematic because one goal of this experience is to predict eruptions by observing the evolution of the internal density of a volcano as function of time. That is why; first tests were done on the Puy-de-Dome volcanoes in order to perform technology/data taking and to make them compatible to active volcanoes. In terms of technology, the steps consists of mounting an autonomous telescope/Multi-telescopes (most appropriate geometry of the telescope, closed gas loop, recycling gas system, independent long-term battery, remote control/acquisition system, monitoring system, technology enable to resist in a hostile environment, coupling telescopes arround the volcano ...). I participated to the campaigns of measurements done arround the Puy-de-Dôme volcano, on R&D of the detectors produces for this project and I developed a Monte Carlo simulation, which reproduces the characteristics of the telescope, its geometry and its different positionning depending of the campaign of measurement. This simulation permits to reproduce the angular atmospheric muon distribution detected by the telescope and their energy distribution with a high precision. The idea of developing simulation for known volcano is to reduce the acquisition time of measurement by coupling data taken by simulating ones. An other way to earn time would be the capability to develop an algorithm able to reconstruct a 3D image from data taken only at 1 position of the telescope. In conclusion, the muography needs the same tools as medical imaging. However, contrary to the medical imaging, the muography is done with detectors smaller than the scanned object, the rate of the particles needed to reconstruct the density profile is lower (long-time measurement) and it is required to scan the object at several position to get a 3D image.
  
  4 articles were published from this job :
  JINST 11 (2016) no.04, P04001
  JINST 11 (2016) no.06, P06014
  JINST 11 (2016) no.09, C09006
  JINST 12 (2017) no.05, P05009

• CNRS - PhD Student

  Lyon (69000) 2010 - 2013 The study of irradiation in molecular systems at the nanometer scale is an innovative field of research in radiation sciences. The DIAM set-up (Dispositif d'Irradiation d'Agrégats Moléculaires) is designed in order to observe and to characterize the consequences of radiation action on model molecular nanosystems such as protonated water clusters. Irradiation induces the fragmentation of the nanosystem in several neutral and charged fragments. The COINTOF (Correlated Ion and Neutral fragments Time of Flight) mass spectrometry techniques allows the correlated detection of the neutral and charged fragments resulting from the dissociation of a mass and velocity selected molecular system. The data processing is performed before the statistical analysis of the fragment production over a large number of fragmentation events. In parallel with the fragmentation channel identification, branching ratio and cross sections are measured with the COINTOF technique. The method is presented here for the collision induced dissociation on argon atoms of protonated water clusters H+(H2O)n, n=2-7, accelerated at 8keV. The detection efficiency, key parameter for the production of quantitative results, is measured from the set of data itself and studied as a function of the amplitude distribution of the detection signal. Finally, a new set-up for production of rare-gas nanodroplets target has been developed
  
  Link for thesis : http://www.theses.fr/2013LYO10262
  1 article was published from this job : PHYSICAL REVIEW A 89, 062705 (2014)

• Université Claude Bernard Lyon 1 - Monitor for undergraduate students and tutor for graduate ones

  Villeurbanne cedex 2010 - 2013 As monitor for undergraduate students I taught :
  1) Optic
  2) Electricity
  3) Special Relativity
  4) Radioprotection
  5) Mathematics
  
  My task consisted of
  - Preparing exercises and academic exams
  - Supervising TDs and TPs.
  - Correcting academic exams.
  
  As tutor for graduate students, I gave my help in the following fields :
  1) Statistical Physic
  2) Quantum Mechanic
  3) Relativistic Quantum Mechanic (QED, QCD, Perturbation, Renormalisation and Gauge theories)
  4) General Relativity
  5) Particle Physic
  
  My task consisted of helping students to solve their exercises and explain concepts not clear for them.
  
  Additional training :
  - Programmation in HTML
  - Programmation in PHP
  - Student psychology
  - Literature search
  - Differential geometry
  - Theory of oriented graphs
  - Lattice mathematical theory
  - Non linear analyse

• Institut de Physique Nucléaire de Lyon - Internship in theoretical physic

  2010 - 2010 Since 1960s, many models have been developed and improved to describe the nuclear matter with still a higher precision according to the experimental measurements. Some of them used the energy density functionals. These models are generally multi-parametrics and the values of the parameters are given by forces. The numerical stability of a model is tested for different forces, which allows to validate them or not and to define the range of nuclei, for which they stay pertinent. So, it is possible to rank them according to their degree of validity (for the different nuclei) and to deduce intrinsic nuclei properties (geometry, nucleon-nucleon/nucleon-hole/hole-hole interactions, influence of the different spin/isospin channels).
  
  The goal of my intership was to establish the behaviour of the infinite symetric nuclear matter and the infinite neutron matter under an external excitation (at zero temperature) by using the linear response theory. For this, a modelisation based on the Skyrme's energy density functional including tensor term, Hartree-Fock-Bogoliubov's and Random Phase Approximation (RPA) formalisms were done to describe the interaction nucleon-nucleon, nucleon-hole and hole-hole in each case and for different spin/isospin channels. The stability of this modelisation was tested for different forces to define their limit of use on the nuclear map and to establish a ranking as function of their pertinences.
  
  1 article was published from this job : PHYSICAL REVIEW C 86, 044308 (2012)

Formations

Pas de formation renseignée

Réseau

• Arthur BURIDON

• Christophe BELLISARIO

• Gaelle GUTIERREZ

• Jean Claude PLENET

• Nicolas PRUGNAUD