Publications (32)
Charmonium Spectrum from Quenched QCD with Overlap Fermions
S. Tamhankar, A. Alexandru, Y. Chen +7
We present the first study of the charmonium spectrum using overlap fermions, on quenched configurations. Simulations are performed on lattices, with Wilson gauge…
Low-dimensional long-range topological structure in the QCD vacuum
I. Horvath, S. J. Dong, T. Draper +5
Lattice topological charge associated with Ginsparg-Wilson fermions exhibits generic topological stability over quantum ensemble of configurations contributing to the QCD path inte…
Inherently Global Nature of Topological Charge Fluctuations in QCD
I. Horvath, A. Alexandru, J. B. Zhang +8
We have recently presented evidence that in configurations dominating the regularized pure-glue QCD path integral, the topological charge density constructed from overlap Dirac ope…
Hadron spectra from overlap fermions on HISQ gauge configurations
S. Basak, S. Datta, A. T. Lytle +3
Adopting a mixed action approach, we report here results on hadron spectra containing one or more charm quarks. We use overlap valence quarks on a background of 2+1+1 flavor HISQ g…
Searching for tetraquarks on the lattice
S. Prelovsek, T. Draper, C. B. Lang +4
We address the question whether the lightest scalar mesons sigma and kappa are tetraquarks. We present a search for possible light tetraquark states with J^PC=0^++ and I=0, 1/2, 3/…
A study of pentaquarks on the lattice with overlap fermions
N. Mathur, F. X. Lee, A. Alexandru +8
We present a quenched lattice QCD calculation of spin-1/2 five-quark states with quark content for both positive and negative parities. We do not observe any bound pe…
A Lattice Study of Quark and Glue Momenta and Angular Momenta in the Nucleon
M. Deka, T. Doi, Y. B. Yang +10
We report a complete calculation of the quark and glue momenta and angular momenta in the proton. These include the quark contributions from both the connected and disconnected ins…
The Negativity of the Overlap-Based Topological Charge Density Correlator in Pure-Glue QCD and the Non-Integrable Nature of its Contact Part
I. Horvath, A. Alexandru, J. B. Zhang +7
We calculate the lattice two-point function of topological charge density in pure-glue QCD using the discretization of the operator based on the overlap Dirac matrix. Utilizing dat…
Chiral Logs in Quenched QCD
Y. Chen, S. J. Dong, T. Draper +5
The quenched chiral logs are examined on a lattice with Iwasaki gauge action and overlap fermions. The pion decay constant is used to set the lattice spacin…
Charmonium excited state spectrum in lattice QCD
J. J. Dudek, R. G. Edwards, N. Mathur +1
Working with a large basis of covariant derivative-based meson interpolating fields we demonstrate the feasibility of reliably extracting multiple excited states using a variationa…
Glueball Matrix Elements on Anisotropic Lattices
Y. Chen, S. -J. Dong, T. Draper +8
The glueball-to-vacuum matrix elements of local gluonic operators in scalar, tensor, and pseudoscalar channels are investigated numerically on several anisotropic lattices with the…
Meson spectra from overlap fermion on domain wall gauge configurations
N. Mathur, A. Alexandru, Y. Chen +9
We report meson spectra obtained by using valence overlap fermion propagators generated on a background of 2+1 flavor domain wall fermion gauge configurations on 16^3 X 32, 24^3 X…
Charmonium Spectrum from Quenched QCD with Overlap Fermions
S. Tamhankar, A. Alexandru, Y. Chen +7
We present preliminary results using overlap fermions for the charmonium spectrum, in particular for hyperfine splitting. Simulations are performed on lattices, wi…
Low-Dimensional Long-Range Topological Charge Structure in the QCD Vacuum
I. Horvath, S. J. Dong, T. Draper +5
While sign-coherent 4-dimensional structures cannot dominate topological charge fluctuations in the QCD vacuum at all scales due to reflection positivity, it is possible that enhan…
Chiral extrapolation beyond the power-counting regime
J. M. M. Hall, F. X. Lee, D. B. Leinweber +4
Chiral effective field theory can provide valuable insight into the chiral physics of hadrons when used in conjunction with non-perturbative schemes such as lattice QCD. In this di…
Lattice study of light scalar tetraquarks with I=0,2,1/2,3/2: are sigma and kappa tetraquarks?
S. Prelovsek, T. Draper, C. B. Lang +4
We investigate whether the lightest scalar mesons sigma and kappa have a large tetraquark component, as is strongly supported by many phenomenological studies. A search for possibl…
Excited baryons from Bayesian priors and overlap fermions
F. X. Lee, S. J. Dong, T. Draper +4
Using the constrained-fitting method based on Bayesian priors, we extract the masses of the two lowest states of octet and decuplet baryons with both parities. The calculation is d…
Charm and strange hadron spectra from overlap fermions on HISQ gauge configurations
S. Basak, S. Datta, M. Padmanath +2
We report here results on charm and strange hadron spectra. Adopting a mixed action approach, we use overlap fermions for valence quarks, on a background of 2+1+1 flavours HISQ gau…
Quark Orbital Angular Momentum from Lattice QCD
N. Mathur, S. J. Dong, K. F. Liu +2
We calculate the quark orbital angular momentum of the nucleon from the quark energy-momentum tensor form factors on the lattice. The disconnected insertion is estimated stochastic…
Nonperturbative renormalization of composite operators with overlap fermions
J. B. Zhang, N. Mathur, S. J. Dong +6
We compute non-perturbatively the renormalization constants of composite operators on a quenched lattice with lattice spacing = 0.20 fm for the overlap fermio…
Overlap Valence on 2+1 Flavor Domain Wall Fermion Configurations with Deflation and Low-mode Substitution
A. Li, A. Alexandru, Y. Chen +11
The overlap fermion propagator is calculated on 2+1 flavor domain wall fermion gauge configurations on 16^3 x 32, 24^3 x 64 and 32^3 x 64 lattices. With HYP smearing and low eigenm…
Moments of Nucleon's Parton Distribution for the Sea and Valence Quarks from Lattice QCD
M. Deka, T. Streuer, T. Doi +5
We extend the study of lowest moments, and , of the parton distribution function of the nucleon to include those of the sea quarks; this entails a disconnected inserti…
Probing the nature of phases across the phase transition at finite isospin chemical potential
Gunnar S. Bali, G. Endrodi, Rajiv V. Gavai +1
We compare the low eigenvalue spectra of the Overlap Dirac operator on two sets of configurations at = 0.5 and 1.5 generated with dynamical staggered fermions at thes…
Hadron spectra and Delta_{mix} from overlap quarks on a HISQ sea
S. Basak, S. Datta, N. Mathur +3
We present results of our continuing study on mixed-action hadron spectra and decay constants using overlap valence quarks on MILC's 2+1+1 flavor HISQ gauge configurations. This st…
The parameter in the overlap on domain-wall mixed action
M. Lujan, A. Alexandru, T. Draper +6
A direct calculation of the mixed-action parameter with valence overlap fermions on a domain-wall fermion sea is presented. The calculation is performed on four ensemble…
Quark and Glue Momenta and Angular Momenta in the Proton --- a Lattice Calculation
K. F. Liu, M. Deka, T. Doi +10
We report a complete calculation of the quark and glue momenta and angular momenta in the proton. These include the quark contributions from both the connected and disconnected ins…
The Role of the D13 (1520) Resonance in eta Electroproduction
R. M. Davidson, N. Mathur, N. C. Mukhopadhyay
We investigate the electroproduction of eta mesons below a center of momentum energy of 1.6 GeV, with particular emphasis on the roles of the N*(1535) and N*(1520) resonances. Usin…
Uncovering Low-Dimensional Topological Structure in the QCD Vacuum
I. Horvath, S. J. Dong, T. Draper +5
Recently, we have pointed out that sign-coherent 4-dimensional structures can not dominate topological charge fluctuations in QCD vacuum at all scales. Here we show that an enhance…
Charmonium, and from overlap fermion on DWF configurations
Y. B. Yang, Y. Chen, A. Alexandru +9
We take a new approach to determine the scale parameter , the physical masses of strange and charm quarks through a global fit which incorporates continuum extrapolation, chir…
Glueball Spectrum and Matrix Elements on Anisotropic Lattices
Y. Chen, A. Alexandru, S. J. Dong +10
The glueball-to-vacuum matrix elements of local gluonic operators in scalar, tensor, and pseudoscalar channels are investigated numerically on several anisotropic lattices with the…
Roper Resonance and S_{11}(1535) from Lattice QCD
N. Mathur, Y. Chen, S. J. Dong +5
Using the constrained curve fitting method and overlap fermions with the lowest pion mass at , we observe that the masses of the first positive and negative parity e…
Spectroscopy of light tetraquark states
S. Prelovsek, T. Draper, C. B. Lang +4
We address the question whether the lightest scalar mesons sigma and kappa are tetraquarks, as is strongly supported by many phenomenological studies. We present a search for possi…