CERN Accelerating science

This week (4-9 September 2023), about 700 researchers from all over the world gather in Houston, Texas, USA, to discuss the physics of the Quark Gluon Plasma at the Quark Matter 2023 conference. This is the 30^th Conference in the Quark Matter series, bringing together theoretical and experimental physicists from around the world to discuss new developments in high-energy heavy-ion physics. The ALICE collaboration is reporting new results in 30 parallel session presentations and 60 posters. The conference kicks off on Monday, 4 September with a session of highlight talks including a presentation by ALICE on new measurements including the first results from Run 3 data collected in 2022 with the upgraded detector.

QM2023-ALICE Photos are in the CDS link.

ALICE presents new results on a variety of topics, including the first results from the LHC Run 3 data collected in 2022 with the upgraded detector, which has allowed us to collect a record data sample of more than a trillion events, about 500 times more than our previous data samples. We present a precise measurement of the production rate of excited charmonia (a bound state of a charm and anti-charm quark) compared to those of the ground state in proton-proton collisions down to zero transverse momentum. This is an important reference for similar measurements in collisions of lead ions, where the charmonia dissociates in the plasma. We also report new measurements of momentum correlations of protons which are used to determine the size of the colliding system in proton-proton collisions. These measurements are part of an ongoing program to study the interactions between the particles produced in these collisions.

Besides the new results from Run 3 data, we report many new measurements using the data samples collected in Run 2. These include new measurements, e.g., of charm baryon production in pp collisions, collective effects in proton-lead collisions, quarkonia, and jet production in lead-lead collisions that probe the plasma, novel polarization effects in the heavy flavour mesons D* and J/Psi, a new measurement of the collectivity of beauty hadrons via non-prompt D mesons, and correlations in the number of strange and anti-strange particles and protons and anti-protons in lead-lead collisions. A more complete overview of the new results is given in the ALICE highlights presentation on Monday 4 September.

There will also be dedicated sessions to discuss detectors and instrumentations at the conference, where ALICE presents the planned upgrades to the inner tracking system and a new forward calorimeter for low Bjorken-x physics for Run 4 as well as ALICE 3, a completely new detector system for a precise measurement of properties of Quark Gluon Plasma for Run 5 and 6 at the LHC.

We look forward to a productive conference with lively discussions of the new results presented by ALICE and the other experiments with the experts of the field.