This title appears in the Scientific Report :
2019
Please use the identifier:
http://hdl.handle.net/2128/23233 in citations.
Please use the identifier: http://dx.doi.org/10.1103/PhysRevD.100.074510 in citations.
Excited-state effects in nucleon structure on the lattice using hybrid interpolators
Excited-state effects in nucleon structure on the lattice using hybrid interpolators
It would be very useful to find a way of reducing excited-state effects in lattice QCD calculations of nucleon structure that has a low computational cost. We explore the use of hybrid interpolators, which contain a nontrivial gluonic excitation, in a variational basis together with the standard int...
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Personal Name(s): | Green, Jeremy R. (Corresponding author) |
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Engelhardt, Michael / Hasan, Nesreen / Krieg, Stefan / Meinel, Stefan / Negele, John W. / Pochinsky, Andrew V. / Syritsyn, Sergey N. | |
Contributing Institute: |
John von Neumann - Institut für Computing; NIC Jülich Supercomputing Center; JSC |
Published in: | Physical Review D Physical review / D, 100 100 (2019 2019) 7 7, S. 074510 074510 |
Imprint: |
Melville, NY
Inst.812068
2019
2019-10-24 2019-10-01 |
DOI: |
10.1103/PhysRevD.100.074510 |
Document Type: |
Journal Article |
Research Program: |
The Proton radius and other aspects of nucleon structure from Lattice QCD Computational Science and Mathematical Methods |
Link: |
OpenAccess OpenAccess |
Publikationsportal JuSER |
Please use the identifier: http://dx.doi.org/10.1103/PhysRevD.100.074510 in citations.
It would be very useful to find a way of reducing excited-state effects in lattice QCD calculations of nucleon structure that has a low computational cost. We explore the use of hybrid interpolators, which contain a nontrivial gluonic excitation, in a variational basis together with the standard interpolator with tuned smearing width. Using the clover discretization of the field strength tensor, a calculation using a fixed linear combination of standard and hybrid interpolators can be done using the same number of quark propagators as a standard calculation, making this a cost-effective option. We find that such an interpolator, optimized by solving a generalized eigenvalue problem, reduces excited-state contributions in two-point correlators. However, the effect in three-point correlators, which are needed for computing nucleon matrix elements, is mixed: for some matrix elements such as the tensor charge, excited-state effects are suppressed, whereas for others such as the axial charge, they are enhanced. The results illustrate that the variational method is not guaranteed to reduce the net contribution from excited states except in its asymptotic regime, and suggest that it may be important to use a large basis of interpolators capable of isolating all of the relevant low-lying states. |