Using infinitevolume, continuum QED and lattice QCD for the hadronic lightbylight contribution to the muon anomalous magnetic moment
Abstract
In our previous work, the connected and leading disconnected hadronic lightbylight contributions to the muon anomalous magnetic moment (g — 2) have been computed using lattice QCD ensembles corresponding to physical pion mass generated by the RBC/UKQCD Collaboration. However, the calculation is expected to suffer from a significant finitevolume error that scales like 1/L ^{2} where L is the spatial size of the lattice. In this paper, we demonstrate that this problem is cured by treating the muon and photons in infinitevolume, continuum QED, resulting in a weighting function that is precomputed and saved with affordable cost and sufficient accuracy. We present numerical results for the case when the quark loop is replaced by a muon loop, finding the expected exponential approach to the infinite volume limit and consistency with the known analytic result. Here, we have implemented an improved weighting function which reduces both discretization and finitevolume effects arising from the hadronic part of the amplitude.
 Authors:
 Univ. of Connecticut, Storrs, CT (United States); Brookhaven National Lab. (BNL), Upton, NY (United States)
 Columbia Univ., New York, NY (United States)
 Nagoya Univ., Nagoya (Japan)
 Brookhaven National Lab. (BNL), Upton, NY (United States)
 Publication Date:
 Research Org.:
 Brookhaven National Laboratory (BNL), Upton, NY (United States)
 Sponsoring Org.:
 USDOE Office of Science (SC), High Energy Physics (HEP) (SC25)
 OSTI Identifier:
 1408711
 Report Number(s):
 BNL1144512017JA
Journal ID: ISSN 24700010; PRVDAQ; KA2041012; TRN: US1703307
 Grant/Contract Number:
 SC0012704; AC0206CH11357; FG0292ER40716; SC0011941
 Resource Type:
 Journal Article: Accepted Manuscript
 Journal Name:
 Physical Review D
 Additional Journal Information:
 Journal Volume: 96; Journal Issue: 3; Journal ID: ISSN 24700010
 Publisher:
 American Physical Society (APS)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; g2; muon; quark; lattice; QCD; magnetic; hadronic
Citation Formats
Blum, Thomas, Christ, Norman, Hayakawa, Masashi, Izubuchi, Taku, Jin, Luchang, Jung, Chulwoo, and Lehner, Christoph. Using infinitevolume, continuum QED and lattice QCD for the hadronic lightbylight contribution to the muon anomalous magnetic moment. United States: N. p., 2017.
Web. doi:10.1103/PhysRevD.96.034515.
Blum, Thomas, Christ, Norman, Hayakawa, Masashi, Izubuchi, Taku, Jin, Luchang, Jung, Chulwoo, & Lehner, Christoph. Using infinitevolume, continuum QED and lattice QCD for the hadronic lightbylight contribution to the muon anomalous magnetic moment. United States. doi:10.1103/PhysRevD.96.034515.
Blum, Thomas, Christ, Norman, Hayakawa, Masashi, Izubuchi, Taku, Jin, Luchang, Jung, Chulwoo, and Lehner, Christoph. 2017.
"Using infinitevolume, continuum QED and lattice QCD for the hadronic lightbylight contribution to the muon anomalous magnetic moment". United States.
doi:10.1103/PhysRevD.96.034515.
@article{osti_1408711,
title = {Using infinitevolume, continuum QED and lattice QCD for the hadronic lightbylight contribution to the muon anomalous magnetic moment},
author = {Blum, Thomas and Christ, Norman and Hayakawa, Masashi and Izubuchi, Taku and Jin, Luchang and Jung, Chulwoo and Lehner, Christoph},
abstractNote = {In our previous work, the connected and leading disconnected hadronic lightbylight contributions to the muon anomalous magnetic moment (g — 2) have been computed using lattice QCD ensembles corresponding to physical pion mass generated by the RBC/UKQCD Collaboration. However, the calculation is expected to suffer from a significant finitevolume error that scales like 1/L2 where L is the spatial size of the lattice. In this paper, we demonstrate that this problem is cured by treating the muon and photons in infinitevolume, continuum QED, resulting in a weighting function that is precomputed and saved with affordable cost and sufficient accuracy. We present numerical results for the case when the quark loop is replaced by a muon loop, finding the expected exponential approach to the infinite volume limit and consistency with the known analytic result. Here, we have implemented an improved weighting function which reduces both discretization and finitevolume effects arising from the hadronic part of the amplitude.},
doi = {10.1103/PhysRevD.96.034515},
journal = {Physical Review D},
number = 3,
volume = 96,
place = {United States},
year = 2017,
month = 8
}

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