Influence of the chiral magnetic effect on particle-pair elliptic anisotropy

The chiral magnetic effect (CME) is a phenomenon in which electric charge is separated by a strong magnetic field from local domains of chirality imbalance in quantum chromodynamics. The CME-sensitive, azimuthal correlator difference <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:mrow><a:mi mathvariant="normal">Δ</a:mi><a:mi>γ</a:mi></a:mrow></a:math> between opposite-sign (OS) and same-sign (SS) charged hadron pairs is contaminated by a major physics background proportional to the particle elliptic anisotropy (<c:math xmlns:c="http://www.w3.org/1998/Math/MathML"><c:msub><c:mi>v</c:mi><c:mn>2</c:mn></c:msub></c:math>). The CME signal, on the other hand, contributes to the difference in the pair elliptic anisotropies between OS and SS pairs (<d:math xmlns:d="http://www.w3.org/1998/Math/MathML"><d:mrow><d:mi mathvariant="normal">Δ</d:mi><d:msub><d:mi>v</d:mi><d:mrow><d:mn>2</d:mn><d:mo>,</d:mo><d:mi>pair</d:mi></d:mrow></d:msub></d:mrow></d:math>). We investigate <f:math xmlns:f="http://www.w3.org/1998/Math/MathML"><f:mrow><f:mi mathvariant="normal">Δ</f:mi><f:msub><f:mi>v</f:mi><f:mrow><f:mn>2</f:mn><f:mo>,</f:mo><f:mi>pair</f:mi></f:mrow></f:msub></f:mrow></f:math> and find its sensitivity to CME to be similar to that of the <h:math xmlns:h="http://www.w3.org/1998/Math/MathML"><h:mrow><h:mi mathvariant="normal">Δ</h:mi><h:mi>γ</h:mi></h:mrow></h:math> observable.