A5084020285- Nuclear physics research studies
- Quantum Chromodynamics and Particle Interactions
- Particle physics theoretical and experimental studies
- Nuclear Physics and Applications
- Nuclear reactor physics and engineering
- Atomic and Molecular Physics
- Quantum, superfluid, helium dynamics
- Astronomical and nuclear sciences
- Advanced NMR Techniques and Applications
- Advanced Chemical Physics Studies
- Atomic and Subatomic Physics Research
- Cold Atom Physics and Bose-Einstein Condensates
- High-Energy Particle Collisions Research
- Astro and Planetary Science
- Scientific Research and Discoveries
- Radioactive Decay and Measurement Techniques
- Particle accelerators and beam dynamics
- Dark Matter and Cosmic Phenomena
- High-pressure geophysics and materials
- Radiation Therapy and Dosimetry
- Medical Imaging Techniques and Applications
- Radiopharmaceutical Chemistry and Applications
- Nuclear Materials and Properties
- Physics of Superconductivity and Magnetism
- Cosmology and Gravitation Theories
Chalmers University of Technology
2016-2025
Oak Ridge National Laboratory
2015-2016
University of Tennessee at Knoxville
2015-2016
Lawrence Livermore National Laboratory
2004-2010
Brigham Young University - Idaho
2010
With the goal of developing predictive ab initio capability for light and medium-mass nuclei, two-nucleon three-nucleon forces from chiral effective field theory are optimized simultaneously to low-energy nucleon-nucleon scattering data, as well binding energies radii few-nucleon systems selected isotopes carbon oxygen. Coupled-cluster calculations based on this interaction, named ${\mathrm{NNLO}}_{\mathrm{sat}}$, yield accurate nuclei up $^{40}\mathrm{Ca}$, consistent with empirical...
We optimize the nucleon-nucleon interaction from chiral effective field theory at next-to-next-to-leading order (NNLO). The resulting new force ${\mathrm{NNLO}}_{\mathrm{opt}}$ yields ${\ensuremath{\chi}}^{2}\ensuremath{\approx}1$ per degree of freedom for laboratory energies below approximately 125 MeV. In $A=3$, 4 nucleon systems, contributions three-nucleon forces are smaller than previous parametrizations interactions. use to study properties key nuclei and neutron matter, we demonstrate...
Heavy atomic nuclei have an excess of neutrons over protons, which leads to the formation a neutron skin whose thickness is sensitive details nuclear force. This links properties stars, thereby relating objects that differ in size by orders magnitude. The nucleus ${}^{208}$Pb particular interest because it exhibits simple structure and experimentally accessible. However, computing such heavy has been out reach for ab initio theory. By combining advances quantum many-body methods, statistical...
Nuclear charge radii are sensitive probes of different aspects the nucleon-nucleon interaction and bulk properties nuclear matter; thus, they provide a stringent test challenge for theory. The calcium region has been particular interest, as experimental evidence suggested new magic number at $N = 32$ [1-3], while unexpectedly large increases in [4,5] open questions about evolution size neutron-rich systems. By combining collinear resonance ionization spectroscopy method with $\beta$-decay...
Atomic nuclei exhibit multiple energy scales ranging from hundreds of MeV in binding energies to fractions an for low-lying collective excitations. As the limits nuclear are approached near neutron and proton drip lines, traditional shell structure starts melt with onset deformation emergence coexisting shapes. It is a long-standing challenge describe this multiscale physics starting forces roots quantum chromodynamics. Here, we achieve within unified nonperturbative many-body framework that...
Chiral effective field theory (χEFT) provides a systematic approach to describe low-energy nuclear forces. Moreover, χEFT is able provide well-founded estimates of statistical and uncertainties—although this unique advantage has not yet been fully exploited. We fill gap by performing an optimization analysis all the constants (LECs) up next-to-next-to-leading order. Our protocol corresponds simultaneous fit scattering bound-state observables in pion-nucleon, nucleon-nucleon, few-nucleon...
We optimize $\mathrm{\ensuremath{\Delta}}$-full nuclear interactions from chiral effective field theory. The low-energy constants of the contact potentials are constrained by two-body scattering phase shifts, and properties bound state $A=2$ to 4 nucleon systems matter. pion-nucleon couplings taken a Roy-Steiner analysis. resulting yield accurate binding energies radii for range nuclei $A=16$ $A=132$, provide equations matter realistic symmetry energies. Selected excited states also in...
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...
Ab initio has been used as a label in nuclear theory for over two decades. Its meaning evolved and broadened the years. We present our interpretation, briefly review its historical use, discuss present-day relation to theoretical uncertainty quantification.
Subjecting a physical system to extreme conditions is one of the means often used obtain better understanding and deeper insight into its organization structure. In case atomic nucleus, such approach investigate isotopes that have very different neutron-to-proton (N/Z) ratios than in stable nuclei. Light, neutron-rich exhibit most asymmetric N/Z those lying beyond limits binding, which undergo spontaneous neutron emission exist only as short-lived resonances (about 10-21 s), provide...
We precisely determine the infrared (IR) length scale of no-core shell model (NCSM). In NCSM, $A$-body Hilbert space is truncated by total energy, and IR can be determined equating intrinsic kinetic energy $A$ nucleons in NCSM to that a $3(A-1)$-dimensional hyper-radial well with Dirichlet boundary condition for hyper radius. demonstrate this procedure indeed yields very precise performing large-scale calculations $^{6}$Li. apply our result perform accurate extrapolations bound states...
We sample the posterior probability distributions of low-energy constants (LECs) in <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:mi mathvariant="normal">Δ</a:mi></a:math>-full chiral effective field theory <c:math xmlns:c="http://www.w3.org/1998/Math/MathML"><c:mrow><c:mo>(</c:mo><c:mi>χ</c:mi><c:mi>EFT</c:mi><c:mo>)</c:mo></c:mrow></c:math> up to third order. use eigenvector continuation for fast and accurate emulation likelihood Hamiltonian Monte Carlo draw effectively...
The hyperfine splitting of the $1s$ ground state hydrogenlike Tl has been measured for two stable isotopes using emission spectroscopy in SuperEBIT electron-beam ion trap, giving $3858.22\ifmmode\pm\else\textpm\fi{}0.30 \AA{}$ ${}^{203}{\mathrm{Tl}}^{80+}$ and $3821.84\ifmmode\pm\else\textpm\fi{}0.34 ${}^{205}{\mathrm{Tl}}^{80+}$ with a wavelength difference $\ensuremath{\Delta}\ensuremath{\lambda}=36.38\ifmmode\pm\else\textpm\fi{}0.35 \AA{}.$ This is consistent estimates based on anomaly...
We present the first ab initio structure investigation of loosely bound $^{11}\mathrm{Be}$ nucleus, together with a study lighter isotope $^{9}\mathrm{Be}$. The nuclear these isotopes is particularly interesting because appearance parity-inverted ground state in $^{11}\mathrm{Be}$. Our performed framework no-core shell model. Results obtained using four different, high-precision two-nucleon interactions, model spaces up to $9\ensuremath{\hbar}\ensuremath{\Omega}$, are shown. For both nuclei,...
The unbound isotopes 10Li, 12Li and 13Li have been observed after nucleon-knockout reactions at relativistic energies with 11Li 14Be beams impinging on a liquid hydrogen target. channels Li9+n, Li11+n Li11+2n were analysed in the ALADIN-LAND setup GSI. 10Li data confirm earlier findings, while nuclei for first time. relative-energy spectrum shows that ground state of can be described as virtual s-state scattering length −13.7(1.6) fm. A broad energy was found channel. Based assumption is...
A first-principles description of nuclear systems along the drip lines presents a substantial theoretical and computational challenge. In this paper, we discuss theory roadmap, some key approaches, present selected results with focus on long isotopic chains. An important conclusion, which consistently emerges from these analyses, is that three-nucleon forces are crucial for both global properties detailed structure, many-body correlations due to coupling particle continuum essential as one...
We use halo effective field theory to analyze the universal features of proton nuclei bound due a large $S$-wave scattering length. Our work provides fully field-theoretical treatment in presence repulsive Coulomb interaction. With Lagrangian built from core and valence-proton fields, we derive leading-order expression for charge form factor. Within same framework also calculate radiative capture cross section. present general results at leading order that can be applied any one-proton...
The nature of strongly interacting Fermi gases and magnetism is one the most important studied topics in condensed-matter physics. Still, there are many open questions. A central issue under what circumstances strong short-range repulsive interactions enough to drive magnetic correlations. Recent progress field cold atomic allows address this question very clean systems where both particle numbers, dimensionality can be tuned. Here we study fermionic few-body a dimensional harmonic trap...
Strongly interacting one-dimensional quantum systems often behave in a manner that is distinctly different from their higher-dimensional counterparts. When particle attempts to move environment it will unavoidably have interact and 'push' other particles order execute pattern of motion, irrespective whether the are fermions or bosons. A present frontier both theory experiment mixed species and/or with multiple internal degrees freedom. Here we consider trapped two-component bosons...
Chiral effective field theory $(\ensuremath{\chi}\mathrm{EFT})$, as originally proposed by Weinberg, promises a theoretical connection between low-energy nuclear interactions and quantum chromodynamics (QCD). However, the important property of renormalization-group (RG) invariance is not fulfilled in current implementations its consequences for predicting atomic nuclei beyond two- three-nucleon systems has remained unknown. In this work we present systematic study recent RG-invariant...
We construct efficient emulators for the computation of infinite nuclear matter equation state. These are based on subspace-projected coupled-cluster method which we here develop a new algorithm called small-batch voting to eliminate spurious states that might appear when emulating quantum many-body methods non-Hermitian Hamiltonian. The efficiency and accuracy these facilitate rigorous statistical analysis within explore predictions <a:math...
Nuclear saturation and the symmetry energy are key properties of low-energy nuclear physics that depend on fine details interaction. The equation state around is also an important anchor for extrapolations to higher densities studies neutron stars. Here we develop a unified statistical framework uses realistic forces link theoretical modeling finite nuclei infinite matter. We construct fast accurate emulators nuclear-matter observables employ iterative history-matching approach explore...