Speaker
Description
The ALICE collaboration pursues several upgrades to further extend the reach of heavy-ion physics at the LHC. For LHC Run 4 (2029-2032), ALICE is pioneering the use of bent, wafer-scale pixel sensors to produce truly cylindrical tracking layers with very low material budget to replace the three innermost layers of the inner tracking system. The resulting improvement in pointing resolution will allow new measurements of heavy-flavour hadrons and dielectrons. In addition, a Forward Calorimeter (FoCal) system combines a high-granularity electromagnetic silicon-tungsten calorimeter with excellent two-shower separation for neutral pion reconstruction with a conventional hadronic calorimeter for photon isolation. Direct photon measurements with FoCal will provide unique constraints on the low-x gluon structure of protons and nuclei via forward measurements of direct photons.
Furthermore “ALICE 3” is proposed as the next-generation experiment for LHC Run5 and beyond to address unresolved questions about the quark-gluon plasma by precise measurements of heavy-flavour probes as well as electromagnetic radiation in heavy-ion collisions. In order to achieve the best possible pointing resolution a concept for the installation of a high-resolution vertex tracker in the beampipe is being developed. It is surrounded by a silicon-pixel tracker covering roughly 8 units of pseudorapidity. To achieve the required particle identification performance, a combination of a time-of-flight system and a Ring-Imaging Cherenkov detector is foreseen. Further detectors, such as an electromagnetic calorimeter, a muon identifier, and a dedicated forward detector for ultra-soft photons, are being studied.
In this presentation, I will outline the detector concept as guided by the desired physics reach.
