Three-body states are critical to the dynamics of many hadronic resonances. We show that lattice QCD calculations have reached a stage where these can be accurately resolved. perform calculation over wide range parameters and find all below inelastic threshold agree with predictions from state-of-the-art phenomenological formalism. This also illustrates reliability formalism used connect results infinite volume physics. Our is performed using three positively charged pions, different...

An implementation of estimating the two-to-two $K$-matrix from finite-volume energies based on L\"uscher formalism and involving a Hermitian matrix known as "box matrix" is described. The method includes higher partial waves multiple decay channels. Two fitting procedures for parameters, which properly incorporate all statistical covariances, are discussed. Formulas software handling total spins up to $S=2$ orbital angular momenta $L=6$ obtained in several directions. First tests...

The dynamics of multikaon systems are relevance for several areas nuclear physics. However, even the simplest systems, two and three kaons, hard to prepare study experimentally. Here we show how extract this information using first-principle lattice QCD results. We (i) extend relativistic three-body quantization condition strangeness sector, predicting first time excited level finite-volume spectrum three-kaon at maximal isospin (ii) present a calculation levels system in finite box. compare...

We perform a fit of the finite-volume QCD spectrum three pions at maximal isospin to constrain three-body force. use unitarity-based relativistic three-particle quantization condition, with GWUQCD obtained 315 MeV and 220 pion mass in two-flavor QCD. For heavier we find that data is consistent constant contact term close zero, whereas for lighter see statistically significant energy dependence tension prediction leading order ChPT. Our results also suggest enough levels, two-body amplitude...

Quantum simulations of QCD require digitization the infinite-dimensional gluon field. Schemes for doing this with minimum amount qubits are desirable. We present a practical $SU(3)$ gauge theories via its discrete subgroup $S(1080)$. Using modified action that allows classical down to $a\ensuremath{\approx}0.08\text{ }\text{ }\mathrm{fm}$, low-lying glueball spectrum is computed percent-level precision at multiple lattice spacings and shown extrapolate continuum limit results. This suggests...

The elastic $I=1/2$, $s$- and $p$-wave kaon-pion scattering amplitudes are calculated using a single ensemble of anisotropic lattice QCD gauge field configurations with $N_{\mathrm{f}} = 2+1$ flavors dynamical Wilson-clover fermions at $m_{\pi} 230\mathrm{MeV}$. A large spatial extent $L 3.7\mathrm{fm}$ enables good energy resolution while partial wave mixing due to the reduced symmetries finite volume is treated explicitly.The amplitude well described by Breit-Wigner shape parameters...

Masses, widths, and branching ratios of hadronic resonances are quantified by their pole positions residues with respect to transition amplitudes on the Riemann sheets complex energy-plane. In this study we discuss analytic structure in physical energy region three-body scattering such manifolds. As an application, determine position $a_1(1260)$ meson from ALEPH experiment allowing for $\pi\rho$ coupled channels S- D-wave. We find it be...

Resonant hadronic systems often exhibit a complicated decay pattern in which three-body dynamics play relevant or even dominant role. In this work we focus on the ${a}_{1}(1260)$ resonance. For first time, pole position and branching ratios of resonance are calculated from lattice QCD using one-, two-, three-meson interpolators finite-volume formalism extended to spin coupled channels. This marks new milestone for ab initio studies ordinary resonances along with hybrid exotic hadrons...

Lattice calculations allow us to probe the low-lying, non-perturbative spectrum of QCD using first principles numerical methods. Here we present low-lying in scalar sector with vacuum quantum numbers including, fully dynamical for time, mixing between glueball, q-qbar, and meson-meson operators.

Lattice QCD calculations using gauge smearing for fermion kernels are computationally efficient. Hypercubic blocking (nHYP smearing) has been shown to reduce scaling errors. In this work we use an improved action $N_f=2$ QCD, based on the L\"uscher-Weisz and clover-improved Wilson fermions with nHYP smeared links. We perform a parameter scan in region lattice spacing between $0.066 \mathop{\hbox{fm}}$ $0.115 pion mass $207 \mathop{\hbox{MeV}}$ $834 \mathop{\hbox{MeV}}$. determine as function...

Lattice QCD allows us to probe the low-lying hadron spectrum in finite-volume using a basis of single- and multi-hadron interpolating operators. Here we examine effect including tetraquark operators on scalar meson sectors containing $K_0^*(700)$ ($\kappa$) $a_0(980)$ $N_f = 2 + 1$ QCD, with $m_\pi \approx 230$ MeV. Preliminary results additional states found are shown, possible implications these discussed.

Quantum simulations of QCD require digitization the infinite-dimensional gluon field. Schemes for doing this with minimum amount qubits are desirable. We present a practical $SU(3)$ gauge theories via its discrete subgroup $S(1080)$. Using modified action that allows classical down to $a\approx 0.08$ fm, low-lying glueball spectrum is computed percent-level precision at multiple lattice spacings and shown extrapolate continuum limit results. This suggests scheme sufficient quantum QCD.

A new implementation of estimating the two-to-two K -matrix from finitevolume energies based on Luescher formalism is described. The method includes higher partial waves and multiple decay channels, fitting procedure properly all covariances statistical uncertainties. also simpler than previously used procedures. Formulas software for handling total spins up to S = 2 orbital angular momenta L 6 are presented.

Elastic $I=1/2$, $s$- and $p$-wave $Kπ$ scattering amplitudes are simultaneously calculated using a Lüscher style analysis on single ensemble of dynamical Wilson-clover fermions at $m_π\sim 230$ MeV. Partial wave mixing due to the reduced rotational symmetries finite volume is included up $\ell=2$. We also present finite-volume QCD spectra two large anisotropic lattices ($32^3 \times 256$, $24^3 128$) with 230,\ 390$ MeV respectively. In each symmetry channel, basis one- two-hadron...

Elastic $I=1/2$, $s$- and $p$-wave $K\pi$ scattering amplitudes are simultaneously calculated using a L\"uscher style analysis on single ensemble of dynamical Wilson-clover fermions at $m_\pi \sim 230$ MeV. Partial wave mixing due to the reduced rotational symmetries finite volume is included up $\ell=2$. We also present finite-volume QCD spectra two large anisotropic lattices ($32^3 \times 256$, $24^3 128$) with 230,\ 390$ MeV respectively. In each symmetry channel, basis one- two-hadron...

Lattice QCD calculations of scattering phase shifts and resonance parameters in the two-body sector are becoming precision studies. Early employed L\"uscher's formula for extracting these quantities at lowest order. As become more ambitious, higher-order relations required. In this study we derive quantization conditions introduce a method to transparently cross-check our results. This is an important step given involved derivations formulas. We up $\ensuremath{\ell}=5$ partial waves both...

A field theory involving two interacting scalar fields, previously studied by Rummukainen and Gottlieb, is revisited. Our study not restricted to the limit of large quartic couplings, a Symanzik-improved action used so that continuum dispersion relations work well. The Metropolis method, combined with local microcanonical updating algorithm, employed in our Monte Carlo calculations. Isotropic lattices ranging from $16^3 \times 48$ $53^3 are used, scattering phase shifts determined using...

A field theory involving two interacting scalar fields, previously studied by Rummukainen and Gottlieb, is revisited. Our study not restricted to the limit of large quartic couplings, a Symanzik-improved action used so that continuum dispersion relations work well. The Metropolis method, combined with local microcanonical updating algorithm, employed in our Monte Carlo calculations. Isotropic lattices ranging from $16^3 \times 48$ $53^3 are used, scattering phase shifts determined using...