The precision with which hadronic vacuum polarization (HVP) is obtained determines how accurately important observables, such as the muon anomalous magnetic moment <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mrow><a:msub><a:mrow><a:mi>a</a:mi></a:mrow><a:mrow><a:mi>μ</a:mi></a:mrow></a:msub></a:mrow></a:math> or low-energy running of electromagnetic coupling <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"><c:mi>α</c:mi></c:math>, are...

Drawing on experimental data for baryon resonances, Hamiltonian effective field theory (HEFT) is used to predict the positions of finite-volume energy levels be observed in lattice QCD simulations lowest-lying $J^P=1/2^-$ nucleon excitation. In initial analysis, phenomenological parameters model are constrained by experiment and eigenstate energies a prediction model. The agreement between HEFT predictions results obtained volumes with spatial lengths 2 3 fm excellent. These also admit more...

For long distances in the euclidean time vector-vector correlator ($\rho$) has an exponentially decreasing signal-to-noise ratio. However, vector not only consists of meson but also receives contributions from a two-pion system with same quantum numbers. We measure all propagators energy lower than mass resting and employ generalized eigenvalue problem (GEVP) to resolve different contributing states. Using those we can reconstruct propagator much smaller noise at large distances. In this...

Abstract Lattice QCD calculations of the 2s radial excitation nucleon place state at an&amp;#xD;energy approximately 1.9 GeV, raising possibility that it is associated with N1/2 + (1880)&amp;#xD;and (1710) resonances through mixing two-particle meson-baryon states. The discovery&amp;#xD;of (1880) resonance in pion photoproduction but not πN scattering and small&amp;#xD;width suggest a these would&amp;#xD;be insensitive to manner which pions are permitted dress it. To explore this...

We examine the phase shifts and inelasticities associated with ${N}^{*}(1440)$ Roper resonance, we connect these infinite-volume observables to finite-volume spectrum of lattice QCD using Hamiltonian effective field theory. explore three hypotheses for structure resonance. All are able describe scattering data well. In third hypothesis resonance couples low-lying bare basis-state component ground-state nucleon virtual meson-baryon contributions. Here nontrivial superpositions states...

The positive-parity nucleon spectrum is explored in $2 + 1$-flavour lattice QCD a search for new low-lying energy eigenstates near the regime of Roper resonance. In addition to conventional three-quark operators, we consider novel, local five-quark meson-baryon type interpolating fields that hold promise reveal may have been missed previous analyses. Drawing on phenomenological insight, operators based $\sigma{N}$, $\pi{N}$ and $a_0{N}$ channels are constructed. Spectra produced...

First principles calculations of the form factors baryon excitations are now becoming accessible through advances in lattice-QCD techniques. In this paper, we explore utility parity-expanded variational analysis (PEVA) technique calculating Sachs electromagnetic for proton and neutron. We study two lowest-lying odd-parity demonstrate that at heavier quark masses, these states dominated by behavior consistent with constituent models ${N}^{*}(1535)$ ${N}^{*}(1650)$, respectively. also...

In recent years, the use of variational analysis techniques in lattice QCD has been demonstrated to be successful investigation rest-mass spectrum many hadrons. However, due parity-mixing, more care must taken for investigations boosted states ensure that projected correlation functions provided by correspond same at zero momentum. this paper we present Parity-Expanded Variational Analysis (PEVA) technique, a novel method ensuring and consistent isolation baryons through parity expansion...

The recently-introduced Parity Expanded Variational Analysis (PEVA) technique allows for the isolation of baryon eigenstates at finite momentum free from opposite-parity contamination. In this paper, we establish formalism computing form factors spin-1/2 states using PEVA. Selecting vector current, compare electromagnetic ground state nucleon extracted via to a conventional parity-projection approach. Our results show statistically significant discrepancy between PEVA and analyses. This...

The muon, a short-lived cousin of the electron, has provided longstanding discrepancy between standard model particle physics and experimental measurements. This suggests that not-yet-known or force perturbs muon. discovery such "new physics" would have profound consequences on our understanding Nature. In 2021, attention world was drawn to this when announcement independent confirmation experiment by Fermilab [1] coincided with publication ab-initio calculation (Nature [2]). Our result...

This brief review focuses on the low-lying even- and odd-parity excitations of nucleon obtained in recent lattice QCD calculations. Commencing with a survey 2014-15 literature we'll see that results for first even-parity excitation energy can differ by as much 1 GeV, rather unsatisfactory situation. Following methods used to isolate QCD, drawing advances, how consensus spectrum has emerged among many different groups. To provide insight into nature these states wave functions electromagnetic...

We compute the leading order hadronic vacuum polarization contribution to anomalous magnetic moment of muon. The calculations are performed using four flavors stout smeared staggered quarks, with quark masses at their physical values. continuum limit is taken six different lattice spacings ranging from $0.132\,\text{fm}$ down $0.064\,\text{fm}$. All strong isospin breaking and electromagnetic effects accounted for order. A controlled infinite volume thanks dedicated simulations in box sizes...

The precision with which hadronic vacuum polarization (HVP) is obtained determines how accurately important observables, such as the muon anomalous magnetic moment, a_\mu, or low-energy running of electromagnetic coupling, \alpha, are predicted. two most precise approaches for determining HVP are: dispersive relations combined e+e- to hadrons cross-section data, and lattice QCD. However, results in these display significant tensions, whose origins not understood. Here we present a framework...

Recently, the Budapest-Marseille-Wuppertal collaboration achieved sub-percent precision in evaluation of lowest-order hadronic vacuum polarization contribution to muon $g_\mu-2$. At this level precision, isospin-symmetric QCD is not sufficient. In we review how QED and strong-isospin-breaking effects have been included our work. Isospin breaking implemented by expanding relevant correlation functions second order electric charge $e$ first $m_u-m_d$. The correction terms are then computed...

Recently, the hadronic vacuum polarization contribution to anomalous magnetic moment of muon was determined by BMW collaboration with sub-percent precision. Such a precision requires control many sources uncertainty. One these is uncertainty in determination lattice spacing. In this talk, we present scale setting entering computation. It relies on mass $\Omega$ baryon as input which directly used set our main calculation. also allows us calculate value intermediate quantity $w_0$. Here,...

In this study we employ staggered fermions to calculate the two-pion taste singlet states at rest. Leveraging Clebsch-Gordan coefficients of symmetry group associated with fermions, effectively compute $\pi\pi$ contributions resting $\rho$-meson correlator. To discern distinct energy involved, adopt a generalized eigenvalue problem-solving approach. This work will provide insight into important role played by contribution anomalous magnetic moment muon. paper present our theoretic...

This presentation opens with a brief review of lattice QCD calculations showing the $2s$ radial excitation nucleon sits at approximately 2 GeV, well above Roper resonance position. We then proceed to reconcile this observation experimental scattering data. While idea dressing quark-model states in coupled-channel analysis describe data has been around for decades, it's now possible bring these descriptions finite-volume confrontation lattice-QCD calculations. combination and experiment...

The parity-expanded variational analysis (PEVA) technique enables the isolation of opposite-parity eigenstates at finite momentum. approach has been used to perform first lattice QCD calculations excited-baryon form factors. In particular, these show that low-lying odd-parity nucleon excitations are described well by constituent quark models moderate u and d masses approaching strange mass. Herein, we extend PEVA establish a formalism for determination electromagnetic transition factors in...

In this study we employ staggered fermions to calculate the two-pion taste singlet states at rest. Leveraging Clebsch-Gordan coefficients of symmetry group associated with fermions, effectively compute $\pi\pi$ contributions resting $\rho$-meson correlator. To discern distinct energy involved, adopt a generalized eigenvalue problem-solving approach. This work will provide insight into important role played by contribution anomalous magnetic moment muon. paper present our theoretic...

We review the level of welcomeness that members lattice field theory community feel based on results a survey performed in May and June 2023. While respondents reported generally high levels feeling welcome at conference, women people with diverse gender identities, sexual orientations, ethnic backgrounds religious affiliations less included have more negative experiences conference than their peers. Respondents report they are actively informing themselves about inequities community,...

The parity-expanded variational analysis (PEVA) technique enables the isolation of opposite-parity eigenstates at finite momentum. approach has been used to perform first lattice QCD calculations excited-baryon form factors. In particular, these show that low-lying odd-parity nucleon excitations are described well by constituent quark models moderate <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mi>u</a:mi></a:math> and <c:math...