A5063786122- Quantum Chromodynamics and Particle Interactions
- Nuclear physics research studies
- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Quantum, superfluid, helium dynamics
- Atomic and Subatomic Physics Research
- Atomic and Molecular Physics
- Nuclear Physics and Applications
- Cold Atom Physics and Bose-Einstein Condensates
- Nuclear reactor physics and engineering
- Advanced NMR Techniques and Applications
- Black Holes and Theoretical Physics
- Advanced Chemical Physics Studies
- Cosmology and Gravitation Theories
- Dark Matter and Cosmic Phenomena
- Scientific Research and Discoveries
- Superconducting Materials and Applications
- Neutrino Physics Research
- Pulsars and Gravitational Waves Research
- Physics of Superconductivity and Magnetism
- Quantum chaos and dynamical systems
- Astro and Planetary Science
- Gaussian Processes and Bayesian Inference
- Inorganic Fluorides and Related Compounds
- Agricultural Innovations and Practices
Ohio University
2016-2025
Chalmers University of Technology
2024-2025
University of California, Santa Barbara
2023
Technical University of Darmstadt
2018-2021
GSI Helmholtz Centre for Heavy Ion Research
2018-2021
University of East Anglia
2021
Plymouth Marine Laboratory
2021
George Washington University
2013-2020
University of Manchester
2008-2020
Franklin College
2020
We introduce a new framework for quantifying correlated uncertainties of the infinite-matter equation state derived from chiral effective field theory ($\ensuremath{\chi}\mathrm{EFT}$). Bayesian machine learning via Gaussian processes with physics-based hyperparameters allows us to efficiently quantify and propagate theoretical state, such as $\ensuremath{\chi}\mathrm{EFT}$ truncation errors, quantities. apply this state-of-the-art many-body perturbation calculations nucleon-nucleon...
Bayesian procedures designed to quantify truncation errors in perturbative calculations of quantum chromodynamics observables are adapted expansions effective field theory (EFT). In the approach, such derived from degree-of-belief (DOB) intervals for EFT predictions. Computation these requires specification prior probability distributions ("priors") expansion coefficients. By encoding expectations about naturalness coefficients, this framework provides a statistical interpretation standard...
We formulate a new power-counting scheme for chiral effective field theory of nucleons, pions, and Deltas. This extends perturbation into the Delta-resonance region. calculate nucleon Compton scattering up to next-to-leading order in this theory. The resultant description existing $\gamma$p cross section data is very good photon energies about 300 MeV. also find reasonable numbers spin-independent polarizabilities $\alpha_p$ $\beta_p$.
Nuclear halos emerge as new degrees of freedom near the neutron and proton driplines. They consist a core one or few nucleons which spend most their time in classically-forbidden region outside range interaction. Individual inside are thus unresolved halo configuration, low-energy effective interactions short-range forces between valence nucleons. Similar phenomena occur clusters $^4$He atoms, cold atomic gases Feshbach resonance, some exotic hadrons. In these weakly-bound quantum systems...
The application of effective field theory (EFT) methods to nuclear systems provides the opportunity rigorously estimate uncertainties originating in Hamiltonian.Yet this is just one source uncertainty observables predicted by calculations based on EFTs.We discuss goals quantification such and outline a recipe obtain statistically meaningful error bars for their predictions.We argue that different sources can be accounted within Bayesian framework, as we illustrate using toy model.
Effective field theories (EFTs) organize the description of complex systems into an infinite sequence decreasing importance. Predictions are made with a finite number terms, which induces truncation error that is often left unquantified. We formalize notion EFT convergence and propose Bayesian model for predictions correlated across independent variables, e.g., energy or scattering angle. Central to our approach Gaussian processes encode both naturalness correlation structure coefficients....
We present a calculation of the π−d scattering length with an accuracy few percent using chiral perturbation theory. For first time isospin-violating corrections are included consistently. Using data on pionic deuterium and hydrogen atoms, we extract isoscalar isovector pion–nucleon lengths obtain a+=(7.6±3.1)⋅10−3Mπ−1 a−=(86.1±0.9)⋅10−3Mπ−1. Via Goldberger–Miyazawa–Oehme sum rule, this leads to charged-pion–nucleon coupling constant gc2/4π=13.69±0.20.
We present procedures based on Bayesian statistics for estimating, from data, the parameters of effective field theories (EFTs). The extraction low-energy constants (LECs) is guided by theoretical expectations in a quantifiable way through specification priors. A prior natural-sized LECs reduces possibility overfitting, and leads to consistent accounting different sources uncertainty. set diagnostic tools are developed that analyze fit ensure priors do not bias EFT parameter estimation....
We perform statistically rigorous uncertainty quantification (UQ) for chiral effective field theory ($\ensuremath{\chi}\mathrm{EFT}$) applied to infinite nuclear matter up twice saturation density. The equation of state (EOS) is based on high-order many-body perturbation calculations with nucleon-nucleon and three-nucleon interactions fourth order in the $\ensuremath{\chi}\mathrm{EFT}$ expansion. From these our newly developed Bayesian machine-learning approach extracts size smoothness...
We explore the constraints on three-nucleon force (3NF) of chiral effective field theory ($\chi$EFT) that are provided by bound-state observables in $A=3$ and $A=4$ sectors. Our statistically rigorous analysis incorporates experimental error, computational method uncertainty, uncertainty due to truncation $\chi$EFT expansion at next-to-next-to-leading order. A consistent solution for ${}^3$H binding energy, ${}^4$He energy radius, $\beta$-decay rate can only be obtained if errors included...
We analyze the power counting of two-body currents in nuclear effective field theories (EFTs). find that existence nonperturbative physics at low energies, which is manifest deuteron and $^{1}{S}_{0}$ $NN$ virtual bound state, combined with appearance singular potentials versions EFT incorporate chiral symmetry, modifies renormalization-group flow couplings associated contact operators involve nucleon-nucleon pairs external fields. The order these thereby enhanced respect to...
We present an overview of the 4MOST project at Preliminary Design Review. is a major new wide-field, high-multiplex spectroscopic survey facility under development for VISTA telescope ESO. has broad range science goals ranging from Galactic Archaeology and stellar physics to high-energy physics, galaxy evolution, cosmology. Starting in 2021, will deploy 2436 fibres 4.1 square degree field-of-view using positioner based on tilting spine principle. The feed one high-resolution (R~20,000) two...
Phenomenological R -matrix has been a standard framework for the evaluation of resolved resonance cross section data in nuclear physics many years. It is powerful method comparing different types experimental and combining results measurements order to gain better estimation true underlying sections. Yet practical challenge always uncertainty on both sections at energies interest fit parameters, which can take form level parameters. Frequentist ( χ 2 -based) norm. In this work, Markov Chain...
We present the results of a National Science Foundation (NSF) Project Scoping Workshop, purpose which was to assess current status calculations for nuclear matrix elements governing neutrinoless double-beta decay and determine if more work on them is required. After reviewing important recent progress in application effective field theory, lattice quantum chromodynamics, ab initio nuclear-structure theory decay, we discuss state art nuclear-physics uncertainty quantification then construct...