Hybrid Quarkonia on Asymmetric Lattices (original) (raw)

Quarkonium-nucleus bound states from lattice QCD

Physical Review D

Quarkonium-nucleus systems are composed of two interacting hadronic states without common valence quarks, which interact primarily through multi-gluon exchanges, realizing a color van der Waals force. We present lattice QCD calculations of the interactions of strange and charm quarkonia with light nuclei. Both the strangeonium-nucleus and charmonium-nucleus systems are found to be relatively deeply bound when the masses of the three light quarks are set equal to that of the physical strange quark. Extrapolation of these results to the physical light-quark masses suggests that the binding energy of charmonium to nuclear matter is B NM phys < ∼ 40 MeV.

A study of hybrid quarkonium using lattice QCD

1998

The hybrid quarkonium states are studied using the Born-Oppenheimer expansion. The first step in this expansion is the determination of the energy levels of the gluons in the presence of a static quark-antiquark pair as a function of the quarkantiquark separation. The spectrum of such gluonic excitations is determined from first principles using lattice QCD.

Bottom and charm quark masses from lattice NRQCD

Nuclear Physics B - Proceedings Supplements, 1999

We present new values for the MS masses of b and c quarks based on lattice NRQCD simulations of the Υ(bb) and ψ(cc) systems. These include three measurements of the b mass based on quenched simulations with lattice spacings ranging from 0.05fm to 0.15fm, which we find to be largely independent of lattice spacing. In addition, we find a consistent value from an unquenched simulation at 0.08fm.

Hadroquarkonium from lattice QCD

Physical Review D, 2017

The hadro-quarkonium picture [S. Dubinskiy and M.B. Voloshin, Phys. Lett. B 666, 344 (2008)] provides one possible interpretation for the pentaquark candidates with hidden charm, recently reported by the LHCb Collaboration, as well as for some of the charmonium-like " , , " states. In this picture, a heavy quarkonium core resides within a light hadron giving rise to four-or fivequark/antiquark bound states. We test this scenario in the heavy quark limit by investigating the modification of the potential between a static quark-antiquark pair induced by the presence of a hadron. Our lattice QCD simulations are performed on a Coordinated Lattice Simulations (CLS) ensemble with = 2 + 1 flavours of non-perturbatively improved Wilson quarks at a pion mass of about 223 MeV and a lattice spacing of about = 0.0854 fm. We study the static potential in the presence of a variety of light mesons as well as of octet and decuplet baryons. In all these cases, the resulting configurations are favoured energetically. The associated binding energies between the quarkonium in the heavy quark limit and the light hadron are found to be smaller than a few MeV, similar in strength to deuterium binding. It needs to be seen if the small attraction survives in the infinite volume limit and supports bound states or resonances.

Quarkonium mass splittings in three-flavor lattice QCD

Physical Review D, 2010

We report on calculations of the charmonium and bottomonium spectrum in lattice QCD. We use ensembles of gauge fields with three flavors of sea quarks, simulated with the asqtad improved action for staggered fermions. For the heavy quarks we employ the Fermilab interpretation of the clover action for Wilson fermions. These calculations provide a test of lattice QCD, including the theory of discretization errors for heavy quarks. We provide, therefore, a careful discussion of the results in light of the heavy-quark effective Lagrangian. By and large, we find that the computed results are in agreement with experiment, once parametric and discretization errors are taken into account.

Physics of Heavy Quarks from Lattice QCD

2020

In the last few years, lattice QCD has made a dramatic progress in understanding the physics of hadrons containing heavy quarks, from the first principle. This review summarises the major achievements. I. INTRODUCTION Heavy quarks play a dominant role in the understanding of the weak interactions as well as of what may lie beyond the standard model. Since quarks are always bound into hadrons, and we do not understand the strong interactions rigorously, the results of these phenomena are often expressed in terms of non-perturbative parameters (also called matrix elements) that reflect our knowledge/ignorance of the strong interaction effects. Lattice QCD offers the best route to a non-perturbative determination of these parameters. The field of lattice gauge theories has nowadays achieved a maturity level where statistical errors are beaten down enough to expose systematic effects. This control over systematic effects has helped reliable extraction of matrix elements that allow us to...

The Ψ spectrum from lattice QCD with 2 + 1 flavors of dynamical quarks

Nuclear Physics B - Proceedings Supplements, 2003

We describe the bottomonium spectrum obtained on the MILC configurations which incorporate 2+1 flavors of dynamical quarks. We compare to quenched and 2 flavor results also on MILC configurations. We show that the lattice spacing determination using different quantities shows clear signs of convergence with 2+1 flavors and give results for the leptonic width and hyperfine splitting, in the form of the ratio of the 1st excited state of the Υ to that of the ground state.

The heavy-quark hybrid meson spectrum in lattice QCD

2003

Recent findings on the spectrum of heavy-quark mesons from computer simulations of quarks and gluons in lattice QCD are summarized, with particular attention to quark-antiquark states bound by an excited gluon field. The validity of a Born-Oppenheimer treatment for such systems is discussed. Recent results on glueball masses, the light-quark 1-+ hybrid meson mass, and the static three-quark potential are

Light hadrons from lattice QCD with light (u, d), strange and charm dynamical quarks

Journal of High Energy Physics, 2010

We present results of lattice QCD simulations with mass-degenerate up and down and mass-split strange and charm (N f = 2 + 1 + 1) dynamical quarks using Wilson twisted mass fermions at maximal twist. The tuning of the strange and charm quark masses is performed at two values of the lattice spacing a ≈ 0.078 fm and a ≈ 0.086 fm with lattice sizes ranging from L ≈ 1.9 fm to L ≈ 2.8 fm. We measure with high statistical precision the light pseudoscalar mass m PS and decay constant f PS in a range 270 m PS 510 MeV and determine the low energy parameters f 0 andl 3,4 of SU(2) chiral perturbation theory. We use the two values of the lattice spacing, several lattice sizes as well as different values of the light, strange and charm quark masses to explore the systematic effects. A first study of discretisation effects in light-quark observables and a comparison to N f = 2 results are performed.