$\alpha$-clustering effect on flows of direct photons in heavy-ion collisions

TL;DR

This paper investigates how the $eta$-clustering structure of $^{12}$C influences the flow patterns of direct photons in heavy-ion collisions, suggesting photon flow as a probe for nuclear clustering at Fermi energies.

Contribution

It demonstrates that direct photon flows are sensitive to the initial $eta$-clustering configuration of $^{12}$C, providing a new method to study nuclear structure in heavy-ion collisions.

Findings

Photon energy spectrum matches experimental data.

Direct photon flows differ with $^{12}$C configurations.

Photon flows are sensitive to initial nuclear clustering.

Abstract

In this work, we reconstruct the $\gamma$-photon energy spectrum which is in good agreement with the experimental data of $^{86}$Kr + $^{12}$C at $E/A$ = 44 MeV in the framework of our modified EQMD model. The directed flow and elliptic flow of free protons and direct photons have been investigated by taking $\alpha$-clustering structure of $^{12}$C into account. Comparing with the free proton, the direct photon flows give a clearer information about early stage of nuclear reaction. Difference of collective flows between different configurations of $^{12}$C is observed in this work. This indicates that collective flows of direct photons are sensitive to the initial configuration, therefore the $\gamma$ bremsstrahlung process might be taken as an alternative probe to investigate $\alpha$-clustering structure in light nucleus from heavy ion collisions at Fermi-energy region.