Selecting specific initial configuration using spectator neutrons in U+U collisions

Understand

We present a method to select events with specific initial configuration, namely body-tip, in heavy-ion collisions using deformed Uranium nuclei.

• We propose to use asymmetry in spectator neutron numbers to filter out these body-tip events from the unbiased configurations in U+U collisions.
• We have used a variable S_eta to differentiate between the body-tip and unbiased configurations.
• We have calculated the second order azimuthal anisotropy, namely elliptic flow (v2), for this body-tip configuration in the framework of a transport model and found it to be consistently lower compared to that in unbiased configurations as we expected.