scholarly journals Determination of the N$_f$=12 step scaling function using Möbius domain wall fermions

Author(s):  
Anna Hasenfratz ◽  
Claudio Rebbi ◽  
Oliver Witzel
2018 ◽  
Vol 175 ◽  
pp. 03006 ◽  
Author(s):  
Anna Hasenfratz ◽  
Claudio Rebbi ◽  
Oliver Witzel

Universality of various fermion formulations is well established in QCD-like theories defined around the perturbative g2 = 0 fixed point. These arguments do not apply for conformal systems that exhibit an infrared fixed point at non-vanishing g2 coupling. We investigate the step scaling function for systems with 10 or 12 fundamental flavors using domain wall fermions and compare it to perturbative predictions. We test universality by contrasting our findings to results published in the literature based on staggered fermions.


2018 ◽  
Vol 175 ◽  
pp. 13004 ◽  
Author(s):  
Brian Colquhoun ◽  
Shoji Hashimoto ◽  
Takashi Kaneko

We report on the status of our calculation of the exclusive semileptonic decay, B → πlv; a key process in the determination of the CKM matrix element |Vub|. The Möbius domain wall action is used for both light and heavy quarks on gauge ensembles that include the effects of 2 + 1 flavours of quarks in the sea at three values of the lattice spacing: a ≈ 0.08 fm, a ≈ 0.055 fm, and a ≈ 0.044 fm. Pion masses go down to 300 MeV while heavy quarks masses are as large as 2.44mc. We present preliminary results of form factors from this process, showing dependence on momentum transfer, lattice spacing, and the heavy quark mass.


2012 ◽  
Vol 85 (7) ◽  
Author(s):  
Peter Boyle ◽  
Luigi Del Debbio ◽  
Eoin Kerrane ◽  
James Zanotti

2005 ◽  
Vol 498-499 ◽  
pp. 129-133 ◽  
Author(s):  
Marcos Flavio de Campos ◽  
Fernando José Gomes Landgraf

SmCo5 magnets are usually produced by powder metallurgy route, including milling, compaction and orientation under magnetic field, sintering and heat treatment. The samples produced by powder metallurgy, with grain size around 10 μm, are ideal for determination of intrinsic parameters. The first step for determination of intrinsic magnetic parameters is obtaining images of domain structure in demagnetized samples. In the present study, the domain images were produced by means of Kerr effect, in a optical microscope. After the test of several etchings, Nital appears as the most appropriate for observation of magnetic domains by Kerr effect. Applying Stereology and Domain Theory, several intrinsic parameters of SmCo5 phase were determined: domain wall energy 120 erg/cm2, critical diameter for single domain particle size 2 μm and domain wall thickness 60 Å. In the case of SmCo5, and also other phases with high magnetocrystalline anisotropy, Domain Theory presents several advantages when compared with Micromagnetics.


2018 ◽  
Vol 33 (01) ◽  
pp. 1850012
Author(s):  
Yuko Murakami ◽  
Ken-Ichi Ishikawa

In this paper, we construct the Möbius domain wall fermions (MDWFs) in the Schrödinger functional (SF) scheme for the SU(3) gauge theory by adding a boundary operator at the temporal boundary of the SF scheme setup. Using perturbation theory, we investigate the properties of several constructed MDWFs, including the optimal type domain wall, overlap, truncated domain wall, and truncated overlap fermions. We observe the universality of the spectrum of the effective four-dimensional operator at the tree-level, and fermionic contribution to the universal one-loop beta function is reproduced for MDWFs with a sufficiently large fifth-dimensional extent.


2015 ◽  
Author(s):  
Hideo Matsufuru ◽  
Kei-ichi Nagai ◽  
Norikazu Yamada

Sign in / Sign up

Export Citation Format

Share Document