Latest ALICE results of photon and jet measurements

Abstract

Highly energetic jets and photons are complementary probes for the kinematics and the topology of nuclear collisions. Jets are collimated sprays of charged and neutral particles, which are produced in the fragmentation of hard scattered partons in an early stage of the collision. While traversing the medium formed in nuclear collisions, they lose energy and therefore carry information about the interaction of partons with the medium. The jet substructure is particularly interesting to learn about in-medium modification of the jets and several observables exists to probe it. In contrast to jets, photons are created in all collision stages. There are prompt photons from the initial collision, thermal photons produced in the medium, and decay- and fragmentation photons from later collision stages. Photons escape the medium essentially unaffected after their creation. This article presents recent ALICE results on jet substructure and direct photon measurements in pp, p-Pb and Pb-Pb collisions.