Controlling excitedstate contamination in nucleon matrix elements
Abstract
We present a detailed analysis of methods to reduce statistical errors and excitedstate contamination in the calculation of matrix elements of quark bilinear operators in nucleon states. All the calculations were done on a 2+1 flavor ensemble with lattices of size $$32^3 \times 64$$ generated using the rational hybrid Monte Carlo algorithm at $a=0.081$~fm and with $$M_\pi=312$$~MeV. The statistical precision of the data is improved using the allmodeaveraging method. We compare two methods for reducing excitedstate contamination: a variational analysis and a twostate fit to data at multiple values of the sourcesink separation $$t_{\rm sep}$$. We show that both methods can be tuned to significantly reduce excitedstate contamination and discuss their relative advantages and costeffectiveness. A detailed analysis of the size of source smearing used in the calculation of quark propagators and the range of values of $$t_{\rm sep}$$ needed to demonstrate convergence of the isovector charges of the nucleon to the $$t_{\rm sep} \to \infty $$ estimates is presented.
 Authors:
 Publication Date:
 Research Org.:
 Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)
 Sponsoring Org.:
 USDOE Office of Science (SC), Nuclear Physics (NP) (SC26)
 Contributing Org.:
 Nucleon Matrix Elements (NME) Collaboration
 OSTI Identifier:
 1329018
 Report Number(s):
 JLABTHY162285; DOE/OR/231773842; arXiv:1602.07737
Journal ID: ISSN 24700010; PRVDAQ
 DOE Contract Number:
 AC0500OR22725; KA1401020; AC0506OR23177; SC0011090; FG0296ER40965
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review D; Journal Volume: 93; Journal Issue: 11
 Country of Publication:
 United States
 Language:
 English
Citation Formats
Yoon, Boram, Gupta, Rajan, Bhattacharya, Tanmoy, Engelhardt, Michael, Green, Jeremy, Joó, Bálint, Lin, HueyWen, Negele, John, Orginos, Kostas, Pochinsky, Andrew, Richards, David, Syritsyn, Sergey, and Winter, Frank. Controlling excitedstate contamination in nucleon matrix elements. United States: N. p., 2016.
Web. doi:10.1103/PhysRevD.93.114506.
Yoon, Boram, Gupta, Rajan, Bhattacharya, Tanmoy, Engelhardt, Michael, Green, Jeremy, Joó, Bálint, Lin, HueyWen, Negele, John, Orginos, Kostas, Pochinsky, Andrew, Richards, David, Syritsyn, Sergey, & Winter, Frank. Controlling excitedstate contamination in nucleon matrix elements. United States. doi:10.1103/PhysRevD.93.114506.
Yoon, Boram, Gupta, Rajan, Bhattacharya, Tanmoy, Engelhardt, Michael, Green, Jeremy, Joó, Bálint, Lin, HueyWen, Negele, John, Orginos, Kostas, Pochinsky, Andrew, Richards, David, Syritsyn, Sergey, and Winter, Frank. Wed .
"Controlling excitedstate contamination in nucleon matrix elements". United States.
doi:10.1103/PhysRevD.93.114506. https://www.osti.gov/servlets/purl/1329018.
@article{osti_1329018,
title = {Controlling excitedstate contamination in nucleon matrix elements},
author = {Yoon, Boram and Gupta, Rajan and Bhattacharya, Tanmoy and Engelhardt, Michael and Green, Jeremy and Joó, Bálint and Lin, HueyWen and Negele, John and Orginos, Kostas and Pochinsky, Andrew and Richards, David and Syritsyn, Sergey and Winter, Frank},
abstractNote = {We present a detailed analysis of methods to reduce statistical errors and excitedstate contamination in the calculation of matrix elements of quark bilinear operators in nucleon states. All the calculations were done on a 2+1 flavor ensemble with lattices of size $32^3 \times 64$ generated using the rational hybrid Monte Carlo algorithm at $a=0.081$~fm and with $M_\pi=312$~MeV. The statistical precision of the data is improved using the allmodeaveraging method. We compare two methods for reducing excitedstate contamination: a variational analysis and a twostate fit to data at multiple values of the sourcesink separation $t_{\rm sep}$. We show that both methods can be tuned to significantly reduce excitedstate contamination and discuss their relative advantages and costeffectiveness. A detailed analysis of the size of source smearing used in the calculation of quark propagators and the range of values of $t_{\rm sep}$ needed to demonstrate convergence of the isovector charges of the nucleon to the $t_{\rm sep} \to \infty $ estimates is presented.},
doi = {10.1103/PhysRevD.93.114506},
journal = {Physical Review D},
number = 11,
volume = 93,
place = {United States},
year = {Wed Jun 01 00:00:00 EDT 2016},
month = {Wed Jun 01 00:00:00 EDT 2016}
}

Controlling excitedstate contamination in nucleon matrix elements
We present a detailed analysis of methods to reduce statistical errors and excitedstate contamination in the calculation of matrix elements of quark bilinear operators in nucleon states. All the calculations were done on a 2+1flavor ensemble with lattices of size 32 ^{3} × 64 generated using the rational hybrid Monte Carlo algorithm at a = 0.081 fm and with M _{π} = 312 MeV. The statistical precision of the data is improved using the allmodeaveraging method. We compare two methods for reducing excitedstate contamination: a variational analysis and a 2state fit to data at multiple values of the sourcesink separationmore »Cited by 8 
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