Abstract
Off-central heavy-ion collisions are known to feature magnetic fields with magnitudes and characteristic gradients corresponding to the scale of the strong interactions. In this work, we employ equilibrium lattice simulations of the underlying theory, QCD, involving similar inhomogeneous magnetic field profiles to achieve a better understanding of this system. We simulate three flavors of dynamical staggered quarks with physical masses at a range of magnetic fields and temperatures, and extrapolate the results to the continuum limit. Analyzing the impact of the field on the quark condensate and the Polyakov loop, we find non-trivial spatial features that render the QCD medium qualitatively different as in the homogeneous setup, especially at temperatures around the transition. In addition, we construct leading-order chiral perturbation theory for the inhomogeneous background and compare its prediction to our lattice results at low temperature. Our findings will be useful to benchmark effective theories and low-energy models of QCD for a better description of peripheral heavy-ion collisions.
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Acknowledgments
The authors are grateful for enlightening discussions with Matteo Giordano and Tamás Kovács. We acknowledge support by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) through the CRC-TR 211 “Strong-interaction matter under extreme conditions” — project number 315477589. F.C. acknowledges the support by the State of Hesse within the Research Cluster ELEMENTS (Project ID 500/10.006). Parts of the computations in this work were performed on the GPU cluster at Bielefeld University and on the Goethe-HLR cluster at Goethe University. We thank the computing staff of both institutions for their support.
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Brandt, B.B., Cuteri, F., Endrődi, G. et al. Thermal QCD in a non-uniform magnetic background. J. High Energ. Phys. 2023, 229 (2023). https://doi.org/10.1007/JHEP11(2023)229
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DOI: https://doi.org/10.1007/JHEP11(2023)229