Non-perturbative renormalization in coordinate space for maximally twisted mass fermions with tree-level Symanzik improved gauge action

e report on the status of an ongoing effort by the RQCD and ALPHA Collaborations, aimed at determining leptonic decay constants of charmed mesons. Our analysis is based on large-volume ensembles generated within the CLS effort, employing Nf = 2 + 1 non-perturbatively O(a) improved Wilson quarks, tree-level Symanzik-improved gauge action and open boundary conditions. The ensembles cover lattice spac-ings from a ≈ 0.09 fm to a ≈ 0.05 fm, with pion masses varied from 420 to 200 MeV. To extrapolate to the physical masses, we follow both the (2ml + ms) = const. and the ms = const. lines in parameter space.

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Flux tubes in Nf = 2 + 1 QCD with external magnetic fields

EPJ Web of Conferences ◽

10.1051/epjconf/201817512008 ◽

2018 ◽

Vol 175 ◽

pp. 12008 ◽

Cited By ~ 2

Author(s):

Claudio Bonati ◽

Salvatore Calì ◽

Massimo D’Elia ◽

Michele Mesiti ◽

Francesco Negro ◽

...

Keyword(s):

Magnetic Field ◽

External Magnetic Field ◽

Tree Level ◽

Magnetic Field Direction ◽

Physical Point ◽

Flux Tubes ◽

Gauge Action ◽

Uniform External Magnetic Field ◽

Static Quark ◽

The Magnetic Field

We study the behavior of the confining flux tube in Nf = 2 + 1 QCD at the physical point, discretized with the stout smearing improved staggered quark action and the tree level Symazik gauge action. We discuss how it depends on a uniform external magnetic field, showing how it displays anisotropies with respect to the magnetic field direction. Moreover, we compare the observed anisotropy pattern with that of the static quark-antiquark (QQ̅) potential we obtained in [1, 2].

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Non-perturbative improvement of the axial current in Nf=3 lattice QCD with Wilson fermions and tree-level improved gauge action

Nuclear Physics B ◽

10.1016/j.nuclphysb.2015.05.003 ◽

2015 ◽

Vol 896 ◽

pp. 555-568 ◽

Cited By ~ 17

Author(s):

John Bulava ◽

Michele Della Morte ◽

Jochen Heitger ◽

Christian Wittemeier

Keyword(s):

Lattice Qcd ◽

Axial Current ◽

Tree Level ◽

Gauge Action ◽

Wilson Fermions

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flavours of twisted mass quarks: Cut-off effects at tree-level of perturbation theory

Nuclear Physics B ◽

10.1016/j.nuclphysb.2011.01.018 ◽

2011 ◽

Vol 847 (1) ◽

pp. 17-37

Author(s):

E.V. Luschevskaya ◽

Krzysztof Cichy

Keyword(s):

Perturbation Theory ◽

Tree Level ◽

Twisted Mass

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Renormalisation of quark bilinears with Nf=2 Wilson fermions and tree-level improved gauge action

10.22323/1.042.0241 ◽

2008 ◽

Author(s):

Petros Dimopoulos ◽

Roberto Frezzotti ◽

Gregorio Herdoiza ◽

Vittorio Lubicz ◽

Mauro Papinutto ◽

...

Keyword(s):

Tree Level ◽

Gauge Action ◽

Wilson Fermions

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Progress in computing parton distribution functions from the quasi-PDF approach

EPJ Web of Conferences ◽

10.1051/epjconf/201817506021 ◽

2018 ◽

Vol 175 ◽

pp. 06021 ◽

Cited By ~ 2

Author(s):

Constantia Alexandrou ◽

Krzysztof Cichy ◽

Martha Constantinou ◽

Kyriakos Hadjiyiannakou ◽

Karl Jansen ◽

...

Keyword(s):

Parton Distribution ◽

Distribution Functions ◽

Matrix Elements ◽

Parton Distribution Functions ◽

Mass Collaboration ◽

Twisted Mass ◽

The Future ◽

Systematic Effects ◽

Perturbative Renormalization

We discuss the current developments by the European Twisted Mass Collaboration in extracting parton distribution functions from the quasi-PDF approach. We concentrate on the non-perturbative renormalization prescription recently developed by us, using the RI′ scheme. We show results for the renormalization functions of matrix elements needed for the computation of quasi-PDFs, including the conversion to the MS scheme, and for renormalized matrix elements. We discuss the systematic effects present in the Z-factors and the possible ways of addressing them in the future.

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