A5009426354- Quantum Chromodynamics and Particle Interactions
- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Magnetic confinement fusion research
- Superconducting Materials and Applications
- Fusion materials and technologies
- Particle accelerators and beam dynamics
- Black Holes and Theoretical Physics
- Fluid Dynamics and Turbulent Flows
- Physics of Superconductivity and Magnetism
- Nuclear reactor physics and engineering
- Nuclear Physics and Applications
- Atomic and Subatomic Physics Research
- Wind and Air Flow Studies
- Air Traffic Management and Optimization
- Gyrotron and Vacuum Electronics Research
- Medical Imaging Techniques and Applications
- Advanced Measurement and Metrology Techniques
- Advanced NMR Techniques and Applications
- Nuclear Materials and Properties
- Crystallography and Radiation Phenomena
- Molecular spectroscopy and chirality
- Heat Transfer and Optimization
- Laser-Plasma Interactions and Diagnostics
- Meteorological Phenomena and Simulations
University of Cambridge
2016-2025
Cyprus Institute
2023
University of Cyprus
2023
Royal Military Academy
2020
ITER
2009-2019
Trinity College Dublin
2017-2019
Culham Science Centre
2002-2017
Culham Centre for Fusion Energy
2002-2017
Old Dominion University
2013-2016
Argonne National Laboratory
2011-2013
Studies of the structure excited baryons are key factors to N* program at Jefferson Lab (JLab). Within first year data taking with Hall B CLAS12 detector following 12 GeV upgrade, a dedicated experiment will aim extract electrocouplings high photon virtualities Q 2 . This allow exploration resonances highest ever achieved, kinematic reach up = high-Q make it possible probe nucleon structures distance scales ranging from where effective degrees freedom, such as constituent quarks, dominant...
We determine elastic and coupled-channel amplitudes for isospin-1 meson-meson scattering in $P$-wave, by calculating correlation functions using lattice QCD with light quark masses such that $m_\pi = 236$ MeV a cubic volume of $\sim (4 \,\mathrm{fm})^3$. Variational analyses large matrices computed operator constructions resembling $\pi\pi$, $K\overline{K}$ $q\bar{q}$, several moving frames irreducible representations, leads to discrete energy spectra from which are extracted. In the...
We present for the first time a determination of energy dependence isoscalar $\pi\pi$ elastic scattering phase-shift within first-principles numerical lattice approach to QCD. Hadronic correlation functions are computed including all required quark propagation diagrams, and from these discrete spectrum states in finite volume defined by boundary is extracted. From we obtain $S$-wave up $K\overline{K}$ threshold. Calculations performed at two values $u,d$ mass corresponding $m_\pi = 236, 391$...
The first determination of doubly charmed isospin-0 coupled-channel <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mi>D</a:mi><a:msup><a:mi>D</a:mi><a:mo>*</a:mo></a:msup><a:mo>−</a:mo><a:msup><a:mi>D</a:mi><a:mo>*</a:mo></a:msup><a:msup><a:mi>D</a:mi><a:mo>*</a:mo></a:msup></a:math> scattering amplitudes from lattice quantum chromodynamics (QCD) is presented. finite-volume spectrum computed for three volumes with a light-quark mass corresponding to <c:math...
We explain a form for the rainbow-ladder kernel whose momentum-dependence is consonant with modern DSE- and lattice-QCD results, assess its capability as tool in hadron physics. In every respect tested, this produces results observables that are at least equal to best otherwise obtained comparable approach. Moreover, it enables natural extraction of monotonic running-coupling -gluon-mass.
Using a first-principles calculation within quantum chromodynamics, we are able to determine pattern of strangeness=1 resonances that appear as complex singularities coupled πK-ηK scattering amplitudes. We make use numerical computation in the lattice discretized approach field theory with light quark masses corresponding m(π)∼400 MeV and at single spacing. The energy dependence amplitudes is extracted through their relationship discrete spectrum finite volume, which map out unprecedented detail.
Coupled-channel $\pi K$ and $\eta scattering amplitudes are determined by studying the finite-volume energy spectra obtained from dynamical lattice QCD calculations. Using a large basis of interpolating operators, including both those resembling $q\bar{q}$ construction pair mesons with relative momentum, reliable excited-state spectrum can be obtained. Working at ${m_\pi=391\,\mathrm{MeV}}$, we find gradual increase in $J^P=0^+$ phase-shift which may identified broad scalar resonance that...
We present the first calculation of coupled-channel meson-meson scattering in isospin $=1$, $G$-parity negative sector, with channels $πη$, $K\overline{K}$ and $πη'$, a first-principles approach to QCD. From discrete spectrum eigenstates three volumes extracted from lattice QCD correlation functions we determine energy dependence $S$-matrix, find that $S$-wave features prominent cusp-like structure $πη\to πη$ close threshold coupled rapid turn on amplitudes leading final-state. This behavior...
We present a unified Dyson-Schwinger equation treatment of static and electromagnetic properties pseudoscalar vector mesons, scalar axial-vector diquark correlations, based upon vector-vector contact interaction. A basic motivation for this paper is the need to document comparison between form factors mesons those diquarks that play material role in nucleon structure. notable result, therefore, large degree similarity related meson factors. The simplicity interaction enables computation at...
Ground-state, radially-excited and exotic scalar-, vector- flavoured-pseudoscalar-mesons are studied in rainbow-ladder truncation using an interaction kernel that is consonant with modern DSE- lattice-QCD results. The inability of this to provide realistic predictions for the masses excited- exotic-states confirmed explained. On other hand, its application does information potentially useful proceeding beyond leading-order truncation, e.g.: assisting development projection techniques ease...
We compute nucleon and Roper electromagnetic elastic transition form factors using a Poincar\'e-covariant, symmetry-preserving treatment of $\mathrm{vector}\ifmmode\times\else\texttimes\fi{}\mathrm{vector}$ contact interaction. Obtained thereby, the interactions baryons are typically described by hard factors. In contrasting this behavior with that produced momentum-dependent interaction, one achieves comparisons which highlight scattering resonance electroproduction experiments probe...
Using finite volume techniques in a lattice QCD simulation, the authors study coupled isoscalar $\ensuremath{\pi}\phantom{\rule{0}{0ex}}\ensuremath{\pi}$, $K\phantom{\rule{0}{0ex}}\overline{K}$, $\ensuremath{\eta}\phantom{\rule{0}{0ex}}\ensuremath{\eta}$ scattering. They extract $S$- and $D$-wave scattering amplitudes phases determine resonance parameters for ${f}_{0}$ ${f}_{2}$ mesons $\ensuremath{\sigma}$-meson bound state -- at unphysical light-quark mass used $\ensuremath{\sigma}$ meson...
We present the first determination of hadronic decays lightest exotic $J^{PC}=1^{-+}$ resonance in lattice QCD. Working with SU(3) flavor symmetry, where up, down and strange quark masses approximately match physical strange-quark mass giving $m_π\sim 700$ MeV, we compute finite-volume spectra on six volumes which constrain a scattering system featuring eight coupled channels. Analytically continuing amplitudes into complex energy plane, find pole singularity corresponding to narrow shows...
Elastic scattering amplitudes for $I=0$ $DK$ and $I=0,1$ $D\bar{K}$ are computed in $S$, $P$ $D$ partial waves using lattice QCD with light-quark masses corresponding to $m_π= 239$ MeV 391$ MeV. The $S$-waves contain interesting features including a near-threshold $J^P=0^+$ bound state $DK$, the $D_{s0}^\ast(2317)$, an effect that is clearly visible above threshold, suggestions of $0^+$ virtual $D\bar{K}$. $S$-wave $I=1$ amplitude found be weakly repulsive. finite-volume spectra also...
Focusing on three-pion states with maximal isospin (π^{+}π^{+}π^{+}), we present the first nonperturbative determination of an energy-dependent three-hadron scattering amplitude from first-principles QCD. The calculation combines finite-volume energies, extracted using numerical lattice QCD, a relativistic formalism, required to interpret results. To fully implement latter, also solve integral equations that relate intermediate three-body K matrix physical amplitude. resulting shows rich...
We determine <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:msup><a:mi>J</a:mi><a:mrow><a:mi>P</a:mi><a:mi>C</a:mi></a:mrow></a:msup><a:mo>=</a:mo><a:msup><a:mn>0</a:mn><a:mrow><a:mo>+</a:mo><a:mo>+</a:mo></a:mrow></a:msup></a:math> and <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"><c:msup><c:mn>2</c:mn><c:mrow><c:mo>+</c:mo><c:mo>+</c:mo></c:mrow></c:msup></c:math> hadron-hadron scattering amplitudes in the charmonium energy region up to...
The discovery in the last few years of states belonging to extended charmonium family has highlighted importance closeness decay channels an understanding many these mesons. We aid this debate by illustrating a simple calculational procedure for including effect open and nearby closed channels.
A continuous wave carbon dioxide laser Doppler radar has been developed and applied to remote measurement of atmospheric wind velocity turbulence. The illuminates residual particulate matter in the atmosphere. Radiation scattered by these particles is homodyned with a local oscillator provide signal. performance instrument verified comparison data recorded simultaneously system cup-anemometer-wind-vane system. Data were recorded, for 45 min intervals, single component horizontal at an...
We present the first lattice QCD study of coupled-channel $D\pi$, $D\eta$ and $D_{s}\bar{K}$ scattering in isospin-1/2 three partial waves. Using distillation, we compute matrices correlation functions with bases operators capable resolving both meson meson-meson contributions to spectrum. These are analysed using a variational approach extract finite-volume energy eigenstates. Utilising L\"uscher's method its extensions, constrain amplitudes $S$, $P$ $D$-wave as function energy. By...
We present a determination of the $P$-wave $\pi\pi\to\pi\gamma^\star$ transition amplitude from lattice quantum chromodynamics. Matrix elements vector current in finite-volume are extracted three-point correlation functions, and these we determine infinite-volume using generalization Lellouch-L\"uscher formalism. for range discrete values $\pi\pi$ energy virtuality photon, observe expected dynamical enhancement due to $\rho$ resonance. Describing dependence amplitude, able analytically...
We present the first ab initio calculation of a radiative transition hadronic resonance within quantum chromodynamics (QCD). compute amplitude for ππ→πγ^{⋆}, as function energy ππ pair and virtuality photon, in kinematic regime where couples strongly to unstable ρ resonance. This exploratory is performed using lattice discretization QCD with quark masses corresponding m_{π}≈400 MeV. obtain description dependence amplitude, constrained at 48 points, that we can analytically continue pole...
A bstract We present the first determination of ρπ scattering, incorporating dynamically-coupled partial-waves, using lattice QCD, a first-principles numerical approach to QCD. Considering case isospin-2 , we calculate partial-wave amplitudes with J ≤ 3 and determine degree dynamical mixing between coupled S D -wave channels P = 1 + . The analysis makes use relationship scattering discrete spectrum states in finite volume lattice. Constraints on are provided by over one hundred energy levels...
We present the first lattice QCD calculation of coupled $\pi\omega$ and $\pi\phi$ scattering, incorporating $S$ $D$-wave in $J^P=1^+$. Finite-volume spectra three volumes are determined via a variational analysis matrices two-point correlation functions, computed using large bases operators resembling single-meson, two-meson three-meson structures, with light-quark mass corresponding to pion $m_\pi \approx 391$ MeV. Utilizing relationship between discrete spectrum finite-volume energies...
We present a determination of the isospin-$\frac{1}{2}$ elastic $\ensuremath{\pi}K$ scattering amplitudes in $S$ and $P$ partial waves using lattice quantum chromodynamics. The amplitudes, constrained for large number real-valued energy points, are obtained as function light-quark mass, corresponding to four pion masses between 200 400 MeV, at single spacing. Below first inelastic threshold, $P$-wave amplitude is dominated by pole singularity that evolves from being stable bound state...
Isospin-1/2 $D\pi$ scattering amplitudes are computed using lattice QCD, working in a single volume of approximately $(3.6\; \mathrm{fm})^3$ and with light quark mass corresponding to $m_\pi\approx239$ MeV. The spectrum the elastic energy region is yielding 20 levels. Using L\"uscher finite-volume quantisation condition, these energies translated into constraints on infinite-volume hence enable us map out dependence scattering. By analytically continuing range amplitudes, $D_0^\ast$...