Publications associées à Essai nucléaire

Wigner Gaussian dynamics: Simulating the anharmonic and quantum ionic motion

The atomic motion controls important properties of materials, such as thermal transport, phase transitions, and vibrational spectra. However, simulating the ionic dynamics is exceptionally challenging when quantum fluctuations are relevant (e.g., at low te ...

AMER PHYSICAL SOC2023

Correlation between sonic pulse velocity and flat-jack tests for the estimation of the elastic properties of unreinforced brick masonry: Case studies from Croatia

Savvas Saloustros

Historic urban cores in southern Europe are characterized by a significant number of existing unreinforced masonry structures that are known for their seismic vulnerability. The first step in the preservation of such damaged buildings is condition assessme ...

2023

Efficient Semiclassical Evaluation of Electronic Coherences in Polyatomic Molecules

Jiri Vanicek, Nikolay Golubev

Exposing a molecule to an intense light pulse can create a nonstationary quantum state, thus launching correlated dynamics of electrons and nuclei. Although much had been achieved in the understanding of fundamental physics behind the electron-nuclear inte ...

SWISS CHEMICAL SOC2022

Data-Driven Predictive Models: Calculational Bias in Characterization of Spent Nuclear Fuel

Characteristics of the spent nuclear fuel (SNF) are typically calculated, requiring validation a priori. The validation process relies on the difference between calculations and measurements, namely the bias. Usually, predicting the bias based on benchmark ...

EPFL2022

Measurement of the prompt-production cross-section ratio sigma(chi(c2))/sigma(chi(c1)) in pPb collisions at root s(NN)=8.16 TeV

Lesya Shchutska, Olivier Schneider, Aurelio Bay, Yiming Li, Guido Haefeli, Frédéric Blanc, Christoph Frei, Tatsuya Nakada, Michel De Cian, Elena Graverini, Veronica Sølund Kirsebom, François Fleuret, Ettore Zaffaroni, Matthieu Philippe Luther Marinangeli, Renato Quagliani, Federico Betti, Minh Tâm Tran, Donal Patrick Hill, Aravindhan Venkateswaran, Pietro Marino, Vitalii Lisovskyi, Federico Leo Redi, Violaine Bellée, Elisabeth Maria Niel, Maria Vieites Diaz, Pavol Stefko, Jian Wang, Tara Nanut, Mingkui Wang, Maria Elena Stramaglia, Zhirui Xu, Vladimir Macko, Chao Wang, Guillaume Max Pietrzyk, Yi Zhang, Sebastian Schulte, Lino Ferreira Lopes, Lei Zhang, Surapat Ek-In, Ho Ling Li, , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,

Superconductors for fusion: a roadmap

Pierluigi Bruzzone, Kamil Sedlák, Nikolay Bykovskiy, Rainer Wesche

With the first tokamak designed for full nuclear operation now well into final assembly (ITER), and a major new research tokamak starting commissioning (JT60SA), nuclear fusion is becoming a mainstream potential energy source for the future. A critical par ...

2021

Assessment of representativity of the PETALE experiments for validation of Swiss LWRs ex-core dosimetry calculations

Andreas Pautz, Vincent Pierre Lamirand, Hakim Ferroukhi, Axel Guy Marie Laureau, Dimitri Rochman, Alexander Vasiliev

The international experimental program PETALE will be carried out at the CROCUS research reactor of EPFL. The program aims at measuring neutron penetration in slabs made of materials composing typical LWR reactor pressure vessel. The measurements will be u ...

E D P SCIENCES2020

Bayesian Monte Carlo assimilation for the PETALE experimental programme using inter-dosimeter correlation

Andreas Pautz, Vincent Pierre Lamirand, Dimitri Rochman, Axel Guy Marie Laureau

This article presents the methodology developed to generate and use dosimeter covariances and to estimate nuisance parameters for the PETALE experimental programme. In anticipation of the final experimental results, this work investigates the consideration ...

2020

Uncertainty propagation based on correlated sampling technique for nuclear data applications

Andreas Pautz, Vincent Pierre Lamirand, Axel Guy Marie Laureau, Dimitri Rochman

A correlated sampling technique has been implemented to estimate the impact of cross section modifications on the neutron transport and in Monte Carlo simulations in one single calculation. This implementation has been coupled to a Total Monte Carlo approa ...

2020

Applying SHARK-X to perform data assimilation with the LWR-PROTEUS Phase II integral experiments

Andreas Pautz, Daniel Jerôme Siefman, Mathieu Hursin

Data assimilation methods have recently been implemented in the sensitivity analysis and uncertainty quantification tool SHARK-X. This paper presents how they were used with sensitivity coefficients and randomly-sampled nuclear data to simulate integral pa ...

PERGAMON-ELSEVIER SCIENCE LTD2020

The emergence of magnetic ordering at complex oxide interfaces tuned by defects

Paul Muralt, Vasiliki Tileli, Daesung Park, Gurpreet Singh, Jing Li, Yen-Chun Chen

Complex oxides show extreme sensitivity to structural distortions and defects, and the intricate balance of competing interactions which emerge at atomically defined interfaces may give rise to unexpected physics. In the interfaces of non-magnetic complex ...

Nature Research2020

Data assimilation of post irradiation examination experiments to adjust fission yields

Andreas Pautz, Daniel Jerôme Siefman, Mathieu Hursin

Nuclear data, especially fission yields, create uncertainties in the predicted concentrations of fission products in spent fuel. Herein, we present a new framework that extends data assimilation methods to burnup simulations by using data from post-irradia ...

E D P SCIENCES2020

An Experimental Programme optimized with Uncertainty Propagation: PETALE in the CROCUS Reactor

Andreas Pautz, Vincent Pierre Lamirand, Axel Guy Marie Laureau, Dimitri Rochman

The PETALE experimental programme in the CROCUS reactor at EPFL intends to contribute to the validation and improvement of neutron nuclear data in the MeV energy range for stainless steel, particularly in the prospect of heavy reflector elements of pressur ...

EPJ Web of conference2019

Development and Application of Data Assimilation Methods in Reactor Physics

Daniel Jerôme Siefman

Simulations of nuclear reactor physics can disagree significantly from experimental evidence, even when the most accurate models are used. An important part of this bias from experiment is caused by nuclear data. The nuclear data have inherent uncertaintie ...

EPFL2019

Intercomparison of neutron noise measurement systems in the CROCUS reactor

Andreas Pautz, Vincent Pierre Lamirand, Oskari Ville Pakari, Mathieu Hursin

In the framework of an international collaboration, the critical decay constant (α0 = β/Λ), and delayed neutron fraction (β) of the CROCUS reactor were measured by teams of EPFL/PSI, CEA and SCK•CEN research institutes using the Rossi-α and Power Spectral ...

American Nuclear Society2018

Design of Separated Element Reflector Experiments in CROCUS: PETALE

Andreas Pautz, Vincent Pierre Lamirand, Pavel Frajtag, Mathieu Hursin, Daniel Jerôme Siefman

The present article describes the preliminary design studies for PETALE (Programme d'Etude en Transmission de l'Acier Lourd et ses Elements), an oncoming experimental program in the CROCUS reactor. Within the framework of the Venus-Eole-Proteus collaborati ...

ASTM INTERNATIONAL2018

Stochastic vs. sensitivity-based integral parameter and nuclear data adjustments

Andreas Pautz, Daniel Jerôme Siefman, Mathieu Hursin, Dimitri Rochman

Developments in data assimilation theory allow to adjust integral parameters and cross sections with stochastic sampling. This work investigates how two stochastic methods, MOCABA and BMC, perform relative to a sensitivity-based methodology called GLLS. St ...

SPRINGER HEIDELBERG2018

An FPGA-Based Test System for RRAM Technology Characterization

Giovanni De Micheli, Pierre-Emmanuel Julien Marc Gaillardon, Maxime Victor Thammasack, Armando Biscontini

Resistive random access memory (RRAM) technologies have recently gained large attention from the academic and industrial research communities. Significant efforts have been made to enhance the performance of the memory stacks from both communities through ...

2018

Case Study of Data Assimilation Methods with the LWR-Proteus Phase II Experimental Campaign

Andreas Pautz, Mathieu Hursin, Daniel Jerôme Siefman

This paper describes the application of data assimilation methods to CASMO-5 simulations of a Proteus research reactor experiment. Its focus is a comparison and evaluation of three prominent data assimilation methods: generalized linear least squares, MOCA ...

2017

Design of Separated Element Reflector Experiments in CROCUS: PETALE

Andreas Pautz, Vincent Pierre Lamirand, Pavel Frajtag, Mathieu Hursin, Daniel Jerôme Siefman, Stefan Radman

The present article describes the preliminary design studies for an oncoming experimental programme at the CROCUS facility. CROCUS is a teaching and research zero-power reactor operated by the Laboratory for Reactor Physics and Systems Behaviour (LRS) at t ...

2017