English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We present the corrections to the fermion propagator, to second order in thelattice spacing, O(a^2), in 1-loop perturbation theory. The fermions aredescribed by the clover action and for the gluons we use a 3-parameter familyof Symanzik improved actions. Our calculation has been carried out in a generalcovariant gauge. The results are provided as a polynomial of the cloverparameter, and are tabulated for 10 popular sets of the Symanzik coefficients(Plaquette, Tree-level Symanzik, Iwasaki, TILW and DBW2 action).  We also study the O(a^2) corrections to matrix elements of fermion bilinearoperators that have the form $\bar\Psi\Gamma\Psi$, where $\Gamma$ denotes allpossible distinct products of Dirac matrices. These correction terms areessential ingredients for improving, to O(a^2), the matrix elements of thefermion operators.  Our results are applicable also to the case of twisted mass fermions.  A longer write-up of this work, including non-perturbative results, is inpreparation together with V. Gimenez, V. Lubicz and D. Palao.

O(a^2) corrections to the propagator and bilinears of Wilson / clover fermions