# ZEU-NIC

 2018-10-0811:21 [PUBDB-2018-03722] Report/Journal Article et al Simulating twisted mass fermions at physical light, strange, and charm quark masses [arXiv:1807.00495] Physical review / D D 98(5), 054518 (2018) [10.1103/PhysRevD.98.054518]   We present the QCD simulation of the first gauge ensemble of two degenerate light quarks, a strange and a charm quark with all quark masses tuned to their physical values within the twisted mass fermion formulation. Results for the pseudoscalar masses and decay constants confirm that the produced ensemble is indeed at the physical parameters of the theory. [...] OpenAccess: PDF PDF (PDFA); 2018-10-0809:48 [PUBDB-2018-03714] Report/Journal Article et al Light-Cone Parton Distribution Functions from Lattice QCD [arXiv:1803.02685] Physical review letters 121(11), 112001 (2018) [10.1103/PhysRevLett.121.112001]   We extract parton distribution functions (PDFs) of the nucleon from lattice QCD using an ensemble of gauge field configurations simulated with light quark masses fixed to their physical values. Theoretical and algorithmic improvements that allow such a calculation include momentum smearing to reach large nucleon boosts with reduced statistical errors, nonperturbative renormalization, target mass corrections, and a novel modified matching of lattice QCD results to connect to what is extracted from experimental measurements. [...] OpenAccess: PDF PDF (PDFA); 2018-09-1010:22 [PUBDB-2018-03417] Report/Journal Article Schaefer, S. Testing the event-chain algorithm in asymptotically free models [arXiv:1806.11460] Physical review / D 98(5), 054502 (2018) [10.1103/PhysRevD.98.054502]   We apply the event-chain algorithm proposed by Bernard et al. in 2009 to toy models of lattice QCD. [...] OpenAccess: PDF PDF (PDFA); 2018-07-1810:32 [PUBDB-2018-02633] Report/Journal Article et al A non-perturbative exploration of the high energy regime in $N_{\mathrm{f}}=3$ QCD [CERN-TH-2018-060, DESY 18-044, WUB/18-01, arXiv:1803.10230]   Using continuum extrapolated lattice data we trace a family of running couplings in three-flavour QCD over a large range of scales from about 4 to 128 GeV. The scale is set by the finite space time volume so that recursive finite size techniques can be applied, and Schrödinger functional (SF) boundary conditions enable direct simulations in the chiral limit. [...] OpenAccess: PDF PDF (PDFA); 2018-07-1309:12 [PUBDB-2018-02595] Preprint/Report Schaefer, S. Testing the event-chain algorithm in asymptotically free models [DESY-18-090; arXiv:1806.11460] We apply the event-chain algorithm proposed by Bernard, Krauth and Wilson in 2009 to toy models of lattice QCD. We give a formal prove of stability of the algorithm. [...] 2018-06-1110:41 [PUBDB-2018-02237] Preprint/Report Sommer, R. Large $N$ scaling and factorization in SU($N$) Yang-Mills gauge theory [DESY-18-075; arXiv:1805.11070]   The large $N$ limit of SU($N$) gauge theories is well understood in perturbation theory. Also non-perturbative lattice studies have yielded important positive evidence that t Hoofts predictions are valid. [...] OpenAccess: PDF PDF (PDFA); 2018-05-2812:31 [PUBDB-2018-02116] Preprint/Report et al Symanzik Improvement with Dynamical Charm: A 3+1 Scheme for Wilson Quarks [CERN-TH-2018-084; arXiv:1805.01661; DESY-18-058; HU-EP-18-10]   We discuss the problem of lattice artefacts in QCD simulations enhanced by the introduction of dynamical charmed quarks. In particular, we advocate the use of a massive renormalization scheme with a close to realistic charm mass. [...] 2018-05-2411:31 [PUBDB-2018-02088] Report/Journal Article et al Parton distributions and lattice QCD calculations: A community white paper [DESY-17-185; IFJPAN-IV-2017-19; INT-PUB-17-042; MSUHEP-17-017; NIKHEF-2017-047; OUTP-17-15P; SMU-HEP-17-08; arXiv:1711.07916] Progress in particle and nuclear physics 100, 107 - 160 (2018) [10.1016/j.ppnp.2018.01.007]   In the framework of quantum chromodynamics (QCD), parton distribution functions (PDFs) quantify how the momentum and spin of a hadron are divided among its quark and gluon constituents. Two main approaches exist to determine PDFs. [...] Published on 2018-01-31. Available in OpenAccess from 2019-01-31.: PDF PDF (PDFA); Restricted: PDF PDF (PDFA); 2018-05-2310:59 [PUBDB-2018-02053] Report/Journal Article et al From the $SU(2)$ quantum link model on the honeycomb lattice to the quantum dimer model on the kagome lattice: Phase transition and fractionalized flux strings [arXiv:1712.08300] Physical review / B 97(20), 205108 (2018) [10.1103/PhysRevB.97.205108]   We consider the (2+1)-dimensional SU(2) quantum link model on the honeycomb lattice and show that it is equivalent to a quantum dimer model on the kagome lattice. The model has crystalline confined phases with spontaneously broken translation invariance associated with pinwheel order, which is investigated with either a Metropolis or an efficient cluster algorithm [...] OpenAccess: PDF PDF (PDFA); 2018-05-2310:56 [PUBDB-2018-02052] Report/Journal Article et al Strange nucleon electromagnetic form factors from lattice QCD [arXiv:1801.09581] Physical review / D 97(9), 094504 (2018) [10.1103/PhysRevD.97.094504]   We evaluate the strange nucleon electromagnetic form factors using an ensemble of gauge configurations generated with two degenerate maximally twisted mass clover-improved fermions with mass tuned to approximately reproduce the physical pion mass. In addition, we present results for the disconnected light quark contributions to the nucleon electromagnetic form factors [...] OpenAccess: PDF PDF (PDFA);