The heaviest element which has been found in nature is uranium with 92 protons. So far, the elements up to atomic number 118 (oganesson) have been discovered and synthesised in the laboratory and the last one was named after the physicist Y. Oganessian in 2016. All transuranium elements are radioactive and their production rates decrease with increasing number of protons. An Island of...
New energy-efficient computer architectures inspired by the mammalian brain have been growing as an alternative to traditional von Neumann computing. Yet, existing hardware implementations use electrons as charge carriers, while neurons rely on transport of ions for both computation and the building of memory. In my presentation, I will show how a two-dimensional electrolyte confined between...
One of the main questions of fundamental physics is the action of gravity on antimatter. We present here the simulation of the last part of the experiment GBAR at CERN, i.e. the measurement of the free fall acceleration 𝑔̅ of antihydrogen atoms in the gravitational field of Earth. It includes the Monte-Carlo generation of trajectories and the analysis leading to the estimation of 𝑔̅. A...
In the last decade, quantum signals and detectors carved out a place for themselves in mainstream technology. Characterization of those devices at the quantum level is thus a crucial ingredient for the development of quantum technologies. Quantum metrology, on the other hand, is the art of estimating the value of one or more parameters of interest. Recently, it has been shown that the quantum...
One of the current challenges of heavy-material-reflector reactors is the need to precisely model space and energy flux variations at the core-reflector interface. Incorrect representations of reflector effects can introduce significant errors in the resulting calculation (reactivity and reaction rates).
This paper aims to describe a methodology that provides a deterministic solver with the...
Photoacoustic imaging is an emerging biomedical imaging modality combining optical and ultrasound waves to map optical-absorption contrast at centimetric depth with sub-millimeter resolution. The key is the photoacoustic (PA) effect: optically absorbing structures emit ultrasound waves when excited with a ns-laser pulse. To reach cm-depth, PA imaging operates in the near-infrared (NIR) window...
The large increase of pile-up interactions is one of the main experimental challenge for HL-LHC physics program. Covering the pseudo-rapidity region between 2.4 and 4.0, the Hight Granularity Timing Detector (HGTD) is therefore proposed for the ATLAS Phase-II upgrade. Using the ability to distinguish between interactions within an event at different 𝑧 positions or time by high-precision...
The blastocoel is a fluid-filled cavity characteristic of the blastula stage during embryonic development. Its formation is a keystone in the morphogenesis of the mammalian embryo, yet the physical mechanism for its emergence remains unclear.
We recently showed that the blastocoel results from micron-sized cavities, nucleating at the adhesive side of cells and coarsening in a process akin to...
the Experimental and theoretical research related to improving the transfer of a number of authors
have carried out heat using nanoparticles and their results showed that the heat transfer of
nanofluids is very important in this context our work presents a critical model for improved heat
transfer This work is done on the basis of a 2D numerical dimension of heat transport models,
which...
In the paradigm of the Standard Cosmological Model, 83% of the mass density in the Universe cannot be explained with ordinary baryonic matter and requires an additional non-baryonic component. The preferred scenario since the 1980s is weakly interacting massive particles scenario (> 1 GeV) (WIMPS). However, despite many experiments, these particles have still not been detected. This has...
Austenitic stainless steels are used in the nuclear industry to make the internals parts of Pressurized Water Reactors (PWR) such as baffle and former plates. Numerous Baffle-to-Former Bolts (BFB) intergranular failures have been reported as a result of Irradiation Assisted Stress Corrosion Cracking (IASCC) phenomenon. In order to predict the cracking of the grain boundary through a...
We study the gap closure with pressure in Phases III and IV of molecular crystalline hydrogen by Quantum Monte Carlo methods [1]. Nuclear quantum and thermal effects are considered from first principles with Coupled Electron Ion Monte Carlo. The fundamental electronic gaps are obtained from grand-canonical Quantum Monte Carlo methods [2] properly extended to quantum crystals. Nuclear zero...
Neutron Stars are compact objects which interior is subject to extreme densities, gravitational fields and magnetic fields. As such conditions cannot yet be reproduced in laboratories, astronuclear physicists use multi-messenger astronomy to turn Neutron Stars into our very own extraterrestrial laboratories for dense matter. We present some recent results established from X-ray measurements of...
More than half of the globe is considered the tropics, thus a proper understanding of the tropical atmosphere is crucial for improved global forecasts as well as the projections of the global climate change. The tropical atmosphere is traditionally considered dominated by moist cumulus convection associated with strongly divergent horizontal flows. The Madden-Julian Oscillation (MJO) is the...
For the commissioning of JT-60SA Tokamak (Japan, beginning of 2021, Project decided in the framework of Broader Approach to ITER Tokamak Project), all the superconducting coils have to be energized with a set of reduced and then nominal current after they became superconducting at 4.5 K cooling temperature with supercritical helium forced flow in Cable-In-Conduit Conductors (CICC).
An...
Laser-plasma acceleration is used to accelerate charged particles and can minimize the size of the next-generation accelerators. However, compared to radiofrequency accelerators, the energies of particles are still low. The ion beam produced by the interaction of the target medium and the high-power laser depends mainly on the laser parameters and the target characteristics. To enhance the ion...
The advent of time-domain and multimessenger astronomy opens new perspectives to study the most energetic phenomena of our universe, and identify the mysterious sources of ultra-high-energy cosmic rays and high-energy neutrinos. In my thesis, I developed new analytical and numerical tools to study the production of cosmic rays, gamma rays and neutrinos from various populations of energetic...
Magnetic skyrmions are nanoscale non-collinear configurations of the magnetic order, featuring specific topological properties. This talk will present how the proper balance of several magnetic interactions allows for their stabilization up to room temperature. One key ingredient is the presence of a Dzyaloshinskii-Moriya antisymmetric exchange interaction, which will be discussed from an...
In this contribution, we will present new results on optical and structural properties of WS2 (from the TMD semiconductor family) encapsulated monolayer, at the tens of nanometer scale. The strength of this work is the correlation of optical spectra at the nanoscale with structural and chemical maps, connecting what is usually available in optical diffraction limited techniques, such as...
Stars are formed when a humongous molecular clouds collapses under its own gravity giving rise to multiple local collapses within the cloud itself. Stars are never formed in isolation and are always formed in groups. When one cloud collapses it gives rise to formation of multiple stars in the same system. When formed this way the stars share similar chemical properties and are of same ages...
Inflation is a hypothetical very early period of the universe when it was expanding exponentially. It has been introduced to explain the homogeneity and the flatness of the observed universe. Remarkably, inflation provides a very nice explanation for the origin of the tiny fluctuations that we observe in the cosmic microwave background: all the known particles come from one single scalar field...
Resistance to fracture is an essential property for manufacturers, in particular those who work with elastomers. In a highly deformed crosslinked polymer, the force to which each chain is subjected depends on the local structure of the network (length of the chains, number of entanglements, local geometry, etc.). In general, a chain breaking is caused by extreme tension. Following a chain...
Measurements of top quark spin observables in tt ̄ events represents a unique possibility to test the standard model (SM) predictions and probe the new physics effects. Potential deviations from the SM expectations are parametrized within the framework of the Effective Field Theory (EFT). In this presentation, we introduce how to measure the spin correlation between top quarks and we cover...
Brownian motion is certainly one of the most popular stochastic process to model particles in interaction with their surrounding environment. In its simplest form, Brownian motion is driven by an uncorrelated white noise induced by thermal fluctuations. Thanks to its universality, it has proven to be a successful model to describe a wide range of first-passage phenomena whereby a particular...
Mott insulators are materials which should have metallic properties according to tight-binding calculations, but are found to have insulating properties instead. This discrepancy between theory and experiments can be explained with the failure of the independent-electron approximation to account for Coulomb interactions, which are not negligible in such materials. When this contribution is...
