openQ*D simulation code for QCD+QED

TL;DR

The paper introduces openQ*D, a new simulation code for QCD+QED that builds on openQCD-1.6, featuring efficient algorithms and dynamical photon fields, with initial performance tests and public availability.

Contribution

It presents openQ*D, a novel simulation code for QCD+QED with C* boundary conditions, incorporating advanced algorithms and dynamical photon fields, extending previous openQCD capabilities.

Findings

Code demonstrates efficiency with inherited features from openQCD-1.6

Includes dynamical photon field treatment with C* boundary conditions

Initial performance analysis shows promising results

Abstract

The openQ*D code for the simulation of QCD+QED with C$^\star$ boundary conditions is presented. This code is based on openQCD-1.6, from which it inherits the core features that ensure its efficiency: the locally-deflated SAP-preconditioned GCR solver, the twisted-mass frequency splitting of the fermion action, the multilevel integrator, the 4th order OMF integrator, the SSE/AVX intrinsics, etc. The photon field is treated as fully dynamical and C$^\star$ boundary conditions can be chosen in the spatial directions. We discuss the main features of openQ*D, and we show basic test results and performance analysis. An alpha version of this code is publicly available and can be downloaded from http://rcstar.web.cern.ch/ .