Enhancement of baryon-to-meson ratios around jets as a signature of medium response

We present a unique signal of jet-induced medium excitations: the enhancement of baryon-to-meson ratios around the quenched jets. To illustrate this, we study the jet-particle correlations and the ($\Delta \eta, \Delta \phi$) distributions of jet-induced identified particles with respect to the jet direction in Pb+Pb collisions at the LHC via a multi-phase transport model. We find a strong enhancement of baryon-to-meson ratios around the triggered jets in Pb+Pb collisions relative to p+p collisions. The enhancement is more pronounced in more central collisions due to larger jet quenching effect, and is strongest at intermediate $p_T$ region as a result of the coalescence of jet-excited medium partons. Since the lost energy from jets can flow to large angles, jet-triggered baryon-to-meson ratios are more enhanced for larger relative distance $\Delta r$ from the jet axis. We argue that the experimental confirmation of the enhancement of jet-induced baryon-to-meson ratios around the jets will provide an unambiguous evidence for the medium response to jet quenching in heavy-ion collisions.