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Relevant uncertainties on theoretical atomic data are vital to determine the accuracy of plasma diagnostics in a number of areas including in particular the astrophysical study. We present a new calculation of the uncertainties on the…

High Energy Astrophysical Phenomena · Physics 2022-01-19 Liyi Gu , Chintan Shah , Ruitian Zhang

We present a method for computing uncertainties in spectral models, i.e. level populations, line emissivities, and emission line ratios, based upon the propagation of uncertainties originating from atomic data. We provide analytic…

Instrumentation and Methods for Astrophysics · Physics 2015-06-12 Manuel A. Bautista , Vanessa Fivet , Pascal Quinet , Jay Dunn , Theodore R. Gull. Timothy R. Kallman , Claudio Mendoza

The analysis and modelling of a range of plasmas (for example: astrophysical, laser-produced and fusion), require atomic data for a number of parameters, such as energy levels, radiative rates and electron impact excitation rates, or…

Atomic Physics · Physics 2017-10-09 K. M. Aggarwal

Machine learning models have emerged as a very effective strategy to sidestep time-consuming electronic-structure calculations, enabling accurate simulations of greater size, time scale and complexity. Given the interpolative nature of…

There has been a growing request from the X-ray astronomy community for a quantitative estimate of systematic uncertainties originating from the atomic data used in plasma codes. Though there have been several studies looking into atomic…

We present strategies to quantify theoretical uncertainties in modern ab-initio calculations of electromagnetic observables in light and medium-mass nuclei. We discuss how uncertainties build up from various sources, such as the…

The uncertainty quantifications of theoretical results are of great importance to make meaningful comparisons of those results with experimental data and to make predictions in experimentally unknown regions. By quantifying uncertainties,…

Nuclear Theory · Physics 2018-12-10 Sota Yoshida , Noritaka Shimizu , Tomoaki Togashi , Takaharu Otsuka

The predictive capability of a plasma discharge model depends on accurate representations of electron-impact collision cross sections, which determine the key reaction rates and transport properties of the plasma. Although many cross…

Plasma Physics · Physics 2024-10-14 Seung Whan Chung , Todd A. Oliver , Laxminarayan L. Raja , Robert D. Moser

Computational models in chemistry rely on a number of approximations. The effect of such approximations on observables derived from them is often unpredictable. Therefore, it is challenging to quantify the uncertainty of a computational…

Chemical Physics · Physics 2017-04-21 Gregor N. Simm , Jonny Proppe , Markus Reiher

Information about the physical properties of astrophysical objects cannot be measured directly but is inferred by interpreting spectroscopic observations in the context of atomic physics calculations. Ratios of emission lines, for example,…

An overview of quantum-mechanical methods to generate cross-section data for electron collisions with atoms and molecules is presented. Particular emphasis is placed on the time-independent close-coupling approach, since it is particularly…

Plasma Physics · Physics 2016-10-21 Klaus Bartschat , Jonathan Tennyson , Oleg Zatsarinny

Although uncertainty quantification has been making its way into nuclear theory, these methods have yet to be explored in the context of reaction theory. For example, it is well known that different parameterizations of the optical…

Nuclear Theory · Physics 2017-03-01 A. E. Lovell , F. M. Nunes , J. Sarich , S. M. Wild

Solving the electronic Schr\"odinger equation for changing nuclear coordinates provides access to the Born-Oppenheimer potential energy surface. This surface is the key starting point for almost all theoretical studies of chemical processes…

Chemical Physics · Physics 2022-01-14 Markus Reiher

In computational materials science, mechanical properties are typically extracted from simulations by means of analysis routines that seek to mimic their experimental counterparts. However, simulated data often exhibit uncertainties that…

Data Analysis, Statistics and Probability · Physics 2017-12-07 Paul N. Patrone , Anthony J. Kearsley , Andrew M. Dienstfrey

Parity-violating polarized electron scattering from nucleons and nuclei provides an excellent tool to extract valuable information on nuclear and nucleon structure, as well as to determine Standard Model couplings and higher-order radiative…

Nuclear Theory · Physics 2015-04-15 O. Moreno , T. W. Donnelly , R. González-Jiménez , J. A. Caballero

We discuss several aspects of creation of adequate mathematical models in other sciences. In particular, many difficulties stem from great complexity of the source systems and the presence of a variety of uncertain factors. We illustrate…

Optimization and Control · Mathematics 2021-02-19 I. V. Konnov

Simulations using machine learning (ML) models and mechanistic models are often run to inform decision-making processes. Uncertainty estimates of simulation results are critical to the decision-making process because simulation results of…

Machine Learning · Computer Science 2023-08-08 Babajide Kolade

Molecular dynamics simulation is now a widespread approach for understanding complex systems on the atomistic scale. It finds applications from physics and chemistry to engineering, life and medical science. In the last decade, the approach…

Computational Physics · Physics 2021-04-28 Shunzhou Wan , Robert C. Sinclair , Peter V. Coveney

The widespread adoption of machine learning surrogate models has significantly improved the scale and complexity of systems and processes that can be explored accurately and efficiently using atomistic modeling. However, the inherently…

Chemical Physics · Physics 2025-03-13 Federico Grasselli , Sanggyu Chong , Venkat Kapil , Silvia Bonfanti , Kevin Rossi

This guide offers suggestions/insights on uncertainty quantification of nuclear structure models. We discuss a simple approach to statistical error estimates, strategies to assess systematic errors, and show how to uncover…

Nuclear Theory · Physics 2014-05-26 J. Dobaczewski , W. Nazarewicz , P. -G. Reinhard
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