Testing the chiral magnetic and chiral vortical effects in heavy ion collisions

Understand

We devise a test of the Chiral Magnetic and Chiral Vortical effects (CME and CVE) in relativistic heavy ion collisions that relies only on the general properties of triangle anomalies.

• We show that the ratio $R_{EB}=J_E/J_B$ of charge $J_E$ and baryon $J_B$ currents for CME is $R^{\rm CME}_{EB} \to \infty$ for three light flavors of quarks ($N_f =3$), and $R^{\rm CME}_{EB} = 5$ for $N_f =2$, whereas for CVE it is $R^{\rm CVE}_{EB} =0$ for $N_f =3$ and $R^{\rm CME}_{EB} = 1/2$ for $N_f =2$.
• The physical world with light $u,d$ quarks and a heavier $s$ quark is in between the $N_f =2$ and $N_f =3$ cases; therefore, the ratios $R_{EB}$ for CME and CVE should differ by over an order of magnitude.
• Since the ratio of electric charge and baryon asymmetries is proportional to $R_{EB}$, the measurement of baryon and electric charge asymmetry fluctuations should allow to separate clearly the CME and CVE contributions.