Lattice calculation caveats and challenges
Sponsored Links
This presentation is the property of its rightful owner.
1 / 9

Lattice Calculation: Caveats and Challenges PowerPoint PPT Presentation

  • Uploaded on
  • Presentation posted in: General

Lattice Calculation: Caveats and Challenges. What lattice can and cannot do Caveats of calculating meson masses Gluebal How about the width? Heavy-light mesons Glueballs. What Can We Use Lattice to Calculate?.

Download Presentation

Lattice Calculation: Caveats and Challenges

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript

Lattice Calculation: Caveats and Challenges

  • What lattice can and cannot do

  • Caveats of calculating meson masses

  • Gluebal

  • How about the width?

  • Heavy-light mesons

  • Glueballs

What Can We Use Lattice to Calculate?

  • Masses, decay constants, form factors, matrix elements, etc.

  • Due to the Charge- Hermiticity (CH) theorem, all observables are real. Thus, there is no S-matrix.

  • However, one can calculate scattering length and phase shift for elastic scattering and discern multi-quark hadrons by exploring the finite volume dependence.

Lessons Learned from Lattice Calculation of Pentaquark Baryons

  • Hadron masses do not depend on interpolation fields. They only affect the spectral weights in the hadron correlators.

  • Since both the multi-quark hadron (e.g. ) and the muti-hadron state can be generated by the same interpolation field with a specific quantum number (e.g. a0 and πη), one needs to identify both and discern their natures, e.g. through the volume dependence of the spectral weights.

Challenges for calculation

  • Except for σ(600), practically all the tetraquark mesonium candidates are near their respective two-meson thresholds, e.g. f0(980) and a0 (980) are near the threshold. So are

  • are near the DK and DD (DD*) thresholds. It is hard to fit both the mesonium and the two-meson state which are within

  • ~ 100 MeV to each other.

  • Heavy-light mesons: it is more desirable to have the same chiral fermion formalism. One needs to be concerned about the finite ma errors for the heavy quark which demands small lattice spacing a and thus large lattice volume.


Quenched Glueball Spectrum

Quenched spectrum was calculated with ~ 100,000 configurations.

Number of dynamical fermion configurations are typically in the hundreds.

Y. Chen et al, PRD (2006); PDG (2006)

|T|2 in continuum

W on lattice








K. Rummukainen andS. Gottlieb, NP B450, 397 (1995)

Lüscher formula

Hadron Mass and Decay Constant

The two-point Green’s function decays exponentially at large separation of time

Mass M= Ep(p=0), decay constant ~ Φ

  • Login