Multiple jets and $\gamma$-jet correlation in high-energy heavy-ion collisions

Understand

$\gamma$-jet production is considered one of the best probes of the hot quark-gluon plasma in high-energy heavy-ion collisions since the direct $\gamma$ can be used to gauge the initial energy and momentum of the associated jet.

• This is investigated within the Linear Boltzmann Transport (LBT) model for jet propagation and jet-induced medium excitation.
• With both parton energy loss and medium response from jet-medium interaction included, LBT can describe experimental data well on $\gamma$-jet correlation in Pb+Pb collisions at the Large Hadron Collider.
• Multiple jets associated with direct $\gamma$ production are found to contribute significantly to $\gamma$-jet correlation at small $p_T^{\rm jet}<p_T^\gamma$ and large azimuthal angle relative to the opposite direction of $\gamma$.