Space-average electromagnetic fields and EM anomaly weighted by energy density in heavy-ion collisions

Understand

We study the space-average electromagnetic (EM) fields weighted by the energy density in the central regions of heavy ion collisions.

• These average quantities can serve as a barometer for the magnetic-field induced effects such as the magnetic effect, the chiral separation effect and the chiral magnetic wave.
• Comparing with the magnetic fields at the geometric center of the collision, the space-average fields weighted by the energy density are smaller in the early stage but damp slower in the later stage.
• The space average of squared fields as well as the EM anomaly $\mathbf{E}\cdot\mathbf{B}$ weighted by the energy density are also calculated.