Nucleon and pion structure with lattice QCD simulations at physical value of the pion mass

Abstract Employing an all-to-all quark propagator technique, we investigate kaon–nucleon interactions in lattice QCD. We calculate the S-wave kaon–nucleon potentials at the leading order in the derivative expansion in the time-dependent HAL QCD method, using (2+1)-flavor gauge configurations on $32^3 \times 64$ lattices with lattice spacing $a \approx 0.09$ fm and pion mass $m_{\pi} \approx 570$ MeV. We take the one-end trick for all-to-all propagators, which allows us to put the zero-momentum hadron operators at both source and sink and to smear quark operators at the source. We find a stronger repulsive interaction in the $I=1$ channel than in the $I=0$. The phase shifts obtained by solving the Schrödinger equations with the potentials qualitatively reproduce the energy dependence of the experimental phase shifts, and have similar behavior to previous results from lattice QCD without all-to-all propagators. Our study demonstrates that the all-to-all quark propagator technique with the one-end trick is useful for studying interactions in meson–baryon systems in the HAL QCD method, so we will apply it to meson–baryon systems which contain quark–antiquark creation/annihilation processes in our future studies.

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THE NUCLEON MASS AND PION-NUCLEON SIGMA TERM FROM A CHIRAL ANALYSIS OF Nf = 2 + 1 LATTICE QCD WORLD DATA

International Journal of Modern Physics Conference Series ◽

10.1142/s2010194514600891 ◽

2014 ◽

Vol 26 ◽

pp. 1460089 ◽

Cited By ~ 1

Author(s):

L. ALVAREZ-RUSO ◽

T. LEDWIG ◽

M. J. VICENTE VACAS ◽

J. MARTIN-CAMALICH

Keyword(s):

Lattice Qcd ◽

Degrees Of Freedom ◽

Pion Mass ◽

Nucleon Mass ◽

A Value ◽

Natural Size ◽

Sigma Term ◽

Pion Nucleon ◽

Pion Mass Dependence ◽

Energy Constants

Fits of the p4 covariant SU(2) baryon chiral perturbation theory to lattice QCD nucleon mass data from several collaborations for 2 and 2+1 flavors are presented. We consider contributions from explicit Δ(1232) degrees of freedom, finite volume and finite spacing corrections. We emphasize here on our Nf = 2 + 1 study. We obtain low-energy constants of natural size that are compatible with the rather linear pion-mass dependence of the nucleon mass observed in lattice QCD. We report a value of σπN = 41(5)(4) MeV in the 2 flavor case and σπN = 52(3)(8) MeV for 2+1 flavors.

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Nucleon structure from Lattice QCD using a nearly physical pion mass

Physics Letters B ◽

10.1016/j.physletb.2014.05.075 ◽

2014 ◽

Vol 734 ◽

pp. 290-295 ◽

Cited By ~ 50

Author(s):

J.R. Green ◽

M. Engelhardt ◽

S. Krieg ◽

J.W. Negele ◽

A.V. Pochinsky ◽

...

Keyword(s):

Lattice Qcd ◽

Pion Mass ◽

Nucleon Structure ◽

Physical Pion

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Electromagnetic transition form factors, E2/M1 and C2/M1 ratios of the baryon decuplet

The European Physical Journal C ◽

10.1140/epjc/s10052-020-08657-6 ◽

2020 ◽

Vol 80 (11) ◽

Author(s):

June-Young Kim ◽

Hyun-Chul Kim

Keyword(s):

Lattice Qcd ◽

Empirical Data ◽

Pion Mass ◽

Form Factors ◽

The Self ◽

Transition Form ◽

Lattice Data ◽

Electromagnetic Transition ◽

Self Consistent ◽

Good Agreement

AbstractWe investigate the electromagnetic transition form factors of the baryon decuplet to the baryon octet, based on the self-consistent SU(3) chiral quark-soliton model, taking into account the effects of explicit breaking of flavor SU(3) symmetry. We emphasize the $$Q^2$$ Q 2 dependence of the electromagnetic $$N\rightarrow \Delta $$ N → Δ transition form factors and the ratios of E2/M1 and C2/M1 in comparison with the experimental and empirical data. In order to compare the present results of the electromagnetic transition form factors of the $$N\rightarrow \Delta $$ N → Δ with those from lattice QCD, we evaluate the form factors with the pion mass deviated from its physical value. The results of the E2/M1 and C2/M1 ratios are in good agreement with the lattice data. We also present the results of the electromagnetic transition form factors for the decuplet to the octet transitions.

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Lattice QCD study of the rare kaon decay K+→π+νν¯ at a near-physical pion mass

Physical Review D ◽

10.1103/physrevd.100.114506 ◽

2019 ◽

Vol 100 (11) ◽

Cited By ~ 5

Author(s):

Norman H. Christ ◽

Xu Feng ◽

Antonin Portelli ◽

Christopher T. Sachrajda ◽

Keyword(s):

Lattice Qcd ◽

Pion Mass ◽

Kaon Decay ◽

Physical Pion

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Parton Distribution Functions and Lattice QCD

EPJ Web of Conferences ◽

10.1051/epjconf/201920601003 ◽

2019 ◽

Vol 206 ◽

pp. 01003

Author(s):

Huey-Wen Lin

Keyword(s):

Lattice Qcd ◽

Parton Distribution ◽

Pion Mass ◽

Effective Field ◽

Distribution Functions ◽

Large Momentum ◽

Parton Distribution Functions ◽

Proton Structure ◽

Nonperturbative Renormalization ◽

First Time

Recently, there have been rapid developments in lattice-QCD calculations of proton structure, especially in the parton distribution functions (PDFs). We overcame a longstanding obstacle and for the first time in lattice-QCD are able to directly calculate the Bjorken-x dependence of the quark, helicity and transversity distributions. The PDFs are obtained using the large-momentum eﬀective field theory (LaMET) framework where the full Bjorken-x dependence of finite-momentum PDFs, called “quasi-PDFs”, can be calculated on the lattice. The quasi-PDF nucleon matrix elements are renormalized non-perturbatively in RI/MOM-scheme. Following a nonperturbative renormalization of the parton quasi-distribution in a regularization-independent momentum-subtraction scheme, we establish its matching to the $ \overline {{\rm{MS}}} $ PDF and calculate the non-singlet matching coeﬃcient at next-to-leading order in perturbation theory. In this proceeding, I will show the progress that has been made in recent years, highlighting the latest state-of-the art PDF calculations at the physical pion mass. Future impacts on the large-x global PDF fits are also discussed.

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Mass Spectra of Ds and Ωc in Lattice QCD with Nf = 2 + 1 + 1 Domain-Wall Quarks

EPJ Web of Conferences ◽

10.1051/epjconf/201817505015 ◽

2018 ◽

Vol 175 ◽

pp. 05015

Author(s):

Ting-Wai Chiu

Keyword(s):

Domain Wall ◽

Lattice Qcd ◽

Mass Spectra ◽

Pion Mass ◽

High Energy ◽

Lhcb Collaboration ◽

Optimal Domain ◽

Charmed Baryons ◽

Experimental Values ◽

Good Agreement

We perform hybrid Monte Carlo simulation of lattice QCD with Nf = 2+1+1 optimal domain-wall quarks on the 323 × 64 lattice with lattice spacing a ~ 0:06 fm, and generate a gauge ensemble with physical s and c quarks, and pion mass ~ 280 MeV. Using 2-quark (meson) and 3-quark (baryon) interpolating operators, the mass spectra of the lowest-lying states containing s and c quarks (Ds and Ωc) are extracted [1], which turn out in good agreement with the high energy experimental values, together with the predictions of the charmed baryons which have not been observed in experiments. For the five new narrow c states observed by the LHCb Collaboration [2], the lowest-lying Ωc(3000) agrees with our predicted mass 3015(29)(34) MeV of the lowest-lying Ωc with JP = 1/2−. This implies that JP of Ωc(3000) is 1/2−.

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