Speaker
Description
In this talk we present new measurements of semi-inclusive hadron+jet correlations in pp and central Pb-–Pb collisions, using the high-statistics data sample of Run 3. Charged-particle jets recoiling from a high-$p_{\textrm{T}}$ charged hadron trigger are reconstructed with resolution parameters 0.2 and 0.4. We report the distribution of the acoplanarity observable, $\Delta \varphi$, defined as the azimuthal angle between the trigger and the recoiling jet. In pp collisions this observable is sensitive to next-to-leading order hadron and jet production, and in Pb--Pb collisions it probes medium-induced decorrelation. We also report a new study of the substructure of recoil jets, measuring the phase-space distance between the Winner-Takes-All (WTA) and Standard jet axes, which probes the distribution of soft radiation in the jet. Such semi-inclusive measurements extend the exploration of substructure measurements to large R and low jet transverse momentum and can elucidate the physical mechanisms underpinning the striking medium-induced acoplanarity broadening that was recently reported by ALICE.
| Category | Experiment |
|---|---|
| Collaboration (if applicable) | ALICE |
