Dominance of electric fields in the charge splitting of elliptic flow

Abstract In heavy-ion collisions, elliptic flow ( v 2 ) quantifies the azimuthal anisotropy in particle emission, reflecting the medium’s response to initial spatial anisotropies. The presence of Electromagnetic fields produced by the fast moving protons in the nucleus can modify this flow, causing a splitting of v 2 between the produced particles and antiparticles. Hence in this study, we explore this effect, emphasizing the dominant role of electric fields in the charge splitting of elliptic flow, Δ v 2 , as a function of transverse momentum ( p T ). The velocity and temperature profiles of quark-gluon plasma medium is described through thermal model calculations. The electromagnetic field evolution is however determined from the solutions of Maxwell’s equations, assuming constant electric and chiral conductivities. We find that the slower decay of the electric fields compared to the magnetic fields makes its impact on the splitting of the elliptic flow more dominant. We further estimated that the maximum value of ∣〈 eF 〉∣, evaluated by averaging the field values over all spatial points on the hypersurface and across all field components, is approximately <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mo stretchy="false">(</mml:mo> <mml:mn>0.01</mml:mn> <mml:mo>±</mml:mo> <mml:mn>0.0002</mml:mn> <mml:mo stretchy="false">)</mml:mo> <mml:mspace width="0.25em"/> <mml:msubsup> <mml:mrow> <mml:mi>m</mml:mi> </mml:mrow> <mml:mrow> <mml:mi>π</mml:mi> </mml:mrow> <mml:mrow> <mml:mn>2</mml:mn> </mml:mrow> </mml:msubsup> </mml:math> for <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msqrt> <mml:msub> <mml:mi>s</mml:mi> <mml:mrow> <mml:mspace width="0.1em"/> <mml:mtext mathvariant="italic">NN</mml:mtext> <mml:mspace width="0.1em"/> </mml:mrow> </mml:msub> </mml:msqrt> <mml:mo>=</mml:mo> <mml:mn>7.7</mml:mn> <mml:mspace width="0.25em"/> <mml:mspace width="0.1em"/> <mml:mtext>GeV</mml:mtext> <mml:mspace width="0.1em"/> </mml:math> , which could describe the splitting of elliptic flow data within the current experimental uncertainty reasonably well.