This title appears in the Scientific Report :
2018
Please use the identifier:
http://hdl.handle.net/2128/17591 in citations.
Please use the identifier: http://dx.doi.org/10.1103/PhysRevD.97.034504 in citations.
Computing the nucleon charge and axial radii directly at Q² = 0 in lattice QCD
Computing the nucleon charge and axial radii directly at Q² = 0 in lattice QCD
We describe a procedure for extracting momentum derivatives of nucleon matrix elements on the lattice directly at $Q^2=0$. This is based on the Rome method for computing momentum derivatives of quark propagators. We apply this procedure to extract the nucleon isovector magnetic moment and charge rad...
Saved in:
Personal Name(s): | Hasan, Nesreen (Corresponding author) |
---|---|
Green, Jeremy (Corresponding author) / Meinel, Stefan (Corresponding author) / Engelhardt, Michael / Krieg, Stefan / Negele, John / Pochinsky, Andrew / Syritsyn, Sergey | |
Contributing Institute: |
Jülich Supercomputing Center; JSC |
Published in: | Physical Review D Physical review / D, 97 97 (2018 2018) 3 3, S. 034504 034504 |
Imprint: |
Woodbury, NY
Inst.
2018
2018-02-09 2018-02-01 |
DOI: |
10.1103/PhysRevD.97.034504 |
Document Type: |
Journal Article |
Research Program: |
Doktorand ohne besondere Förderung Computational Science and Mathematical Methods |
Link: |
Get full text OpenAccess OpenAccess |
Publikationsportal JuSER |
Please use the identifier: http://dx.doi.org/10.1103/PhysRevD.97.034504 in citations.
We describe a procedure for extracting momentum derivatives of nucleon matrix elements on the lattice directly at $Q^2=0$. This is based on the Rome method for computing momentum derivatives of quark propagators. We apply this procedure to extract the nucleon isovector magnetic moment and charge radius as well as the isovector induced pseudoscalar form factor at $Q^2=0$ and the axial radius. For comparison, we also determine these quantities with the traditional approach of computing the corresponding form factors, i.e. $G^v_E(Q^2)$ and $G_M^v(Q^2)$ for the case of the vector current and $G_P^v(Q^2)$ and $G_A^v(Q^2)$ for the axial current, at multiple $Q^2$ values followed by $z$-expansion fits. We perform our calculations at the physical pion mass using a 2HEX-smeared Wilson-clover action. To control the effects of excited-state contamination, the calculations were done at three source-sink separations and the summation method was used. The derivative method produces results consistent with those from the traditional approach but with larger statistical uncertainties especially for the isovector charge and axial radii. |