20190528 11:31 
[PUBDB201902384]
Report/Journal Article
Francis, A. ; Green, J. R. ; Junnarkar, P. M. ; et al
Lattice QCD study of the H dibaryon using hexaquark and twobaryon interpolators
[CERNTH2018098; DESY18066; HIM201802; MITP18030; TIFRTH1812; arXiv:1805.03966]
We present a lattice QCD spectroscopy study in the isospin singlet, strangeness $2$ sectors relevant for the conjectured $H$ dibaryon. We employ both hexaquark and twobaryon interpolating operators to isolate the ground state in the rest frame and in moving frames. [...]
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ddc:530
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20190429 11:14 
[PUBDB201902113]
Report/Journal Article
Athenodorou, A. ; Finkenrath, J. ; Knechtli, F. ; et al
How perturbative are heavy sea quarks?
[DESY18134; HUEP1828; WUB1803; arXiv:1809.03383]
Effects of heavy sea quarks on the low energy physics are described by an effective theory where the expansion parameter is the inverse quark mass, 1/$M$. At leading order in 1/$M$ the dependence of any low energy quantity on $M$ is given in terms of the ratio of $\Lambda$ parameters of the effective and the fundamental theory. [...]
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20190416 10:29 
[PUBDB201901956]
Report/Journal Article
Bruckmann, F. ; Jansen, K. ; Kühn, S.
O(3) nonlinear sigma model in 1 + 1 dimensions with matrix product states
[arXiv:1812.00944; DESY18213]
We numerically study the spectral properties, the entanglement and the zerotemperature phase structure at nonvanishing chemical potential of the O(3) nonlinear sigma model. Using matrix product states, a particular kind of onedimensional tensor network states, we show that we are able to reach the asymptotic scaling regime and to reproduce the analytical predictions for the mass gap at vanishing chemical potential. [...]
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20190401 09:48 
[PUBDB201901785]
Preprint/Report
Hasan, N. ; Green, J. ; Meinel, S. ; et al
Nucleon axial, scalar, and tensor charges using lattice QCD at the physical pion mass
[arXiv:1903.06487; DESY19044]
We report on lattice QCD calculations of the nucleon isovector axial, scalar, and tensor charges. Our calculations are performed on two 2+1flavor ensembles generated using a 2HEXsmeared Wilsonclover action at the physical pion mass and lattice spacings $a\approx$ 0.116 and 0.093 fm. [...]
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20190314 15:26 
[PUBDB201901546]
Preprint/Report
Caselle, M. ; Nada, A. ; Panero, M. ; et al
Conformal field theory and the hot phase of threedimensional U(1) gauge theory
[arXiv:1903.00491; DESY19027]
We study the hightemperature phase of compact U(1) gauge theory in 2+1 dimensions, comparing the results of lattice calculations with analytical predictions from the conformalfieldtheory description of the lowtemperature phase of the bidimensional XY model. We focus on the twopoint correlation functions of probe charges and the fieldstrength operator, finding excellent quantitative agreement with the functional form and the continuously varying critical indices predicted by conformal field theory..
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20190219 13:14 
[PUBDB201901169]
Report/Journal Article
Garcia Vera, M. F. ; Sommer, R.
Large $N$ scaling and factorization in SU($N$) YangMills gauge theory
[DESY18075; arXiv:1805.11070]
The large $N$ limit of SU($N$) gauge theories is well understood in perturbation theory. Also nonperturbative lattice studies have yielded important positive evidence that t Hoofts predictions are valid. [...]
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20190211 09:44 
[PUBDB201901028]
Journal Article
Gérardin, A. ; Harris, T. ; Meyer, H. B.
Nonperturbative renormalization and $O(a )$improvement of the nonsinglet vector current with $N_f = 2 + 1$ Wilson fermions and treelevel Symanzik improved gauge action
In calculating hadronic contributions to precision observables for tests of the Standard Model in lattice QCD, the electromagnetic current plays a central role. Using a Wilson action with $O(a)$ improvement in QCD with $N_ f$ flavors, a counterterm must be added to the vector current in order for its onshell matrix elements to be $O(a)$ improved. [...]
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20190129 10:01 
[PUBDB201900846]
Report/Journal Article
Carmignotto, M. ; Ali, S. ; Aniol, K. ; et al
Separated Kaon Electroproduction Cross Section and the Kaon Form Factor from 6 GeV JLab Data
[JLABPHY182645; arXiv:1801.01536]
The H1(e,e′K+)Λ reaction was studied as a function of the Mandelstam variable −t using data from the E01004 (FPI2) and E93018 experiments that were carried out in Hall C at the 6 GeV Jefferson Laboratory. The cross section was fully separated into longitudinal and transverse components, and two interference terms at fourmomentum transfers Q2 of 1.00, 1.36, and 2.07GeV2. [...]
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20190116 11:53 
[PUBDB201900523]
Report/Contribution to a conference proceedings
Green, J.
Systematics in nucleon matrix element calculations
[DESY18224, arXiv:1812.10574]
201836th International Symposium on Lattice Field Theory, LATTICE 2018, East LansingEast Lansing, USA, 22 Jul 2018  28 Jul 20182018072220180728
15 pp. (2018) [10.3204/PUBDB201900523]2018
The current status of calculations of simple nucleon structure observables is reviewed, with a focus on the axial charge. A major challenge is the combination of an exponentially decaying signaltonoise ratio and the need for large sourcesink separations to eliminate excitedstate contributions; efforts to understand and deal with this problem are the focus of the largest section of this review. [...]
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20190114 15:08 
[PUBDB201900443]
Preprint/Report
Alexandrou, C. ; Bacchio, S. ; Constantinou, M. ; et al
Proton and neutron electromagnetic form factors from lattice QCD
[arXiv:1812.10311; DESY18033]
The electromagnetic form factors of the proton and the neutron are computed within lattice QCD using simulations of maximally twisted mass fermions with masses fixed to their physical values. We analyse two new ensembles of $N_f=2$ and $N_f=2+1+1$ and use several values of the sinksource time separation in the range of 1.0 fm to 1.6 fm to ensure ground state identification. [...]
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