Measurement of the Lund jet plane in $pp$ collisions at $\sqrt{s}$ = 200 GeV with STAR

23 Jun 2026, 19:40
20m
Garland 064

Garland 064

Poster presentation Poster session

Speaker

Emily Pottebaum (Yale University (US))

Description

The Lund jet plane (LJP) is an experimental observable that maps the emission pattern of a jet onto a phase space representation of QCD radiation. Selecting on specific regions of the LJP allows one to isolate perturbative and non-perturbative contributions to the multi-scale evolution of a jet, making the LJP a powerful tool for precision jet substructure measurements. The primary LJP is constructed by stepping backward through the clustering tree following the hardest prong, or primary emitter, at each splitting. Emissions are characterized according to their splitting angle $\Delta R$, hardness $k_t$, and momentum-sharing fraction $z$ relative to the primary emitter.

We present our work toward the first measurement of the primary LJP at RHIC using $\sqrt{s} = 200$ GeV $pp$ collisions collected by the STAR experiment. Jets with resolution parameter $R = 0.4$ and transverse momenta $p_{T,jet} > 15$ GeV/$c$ are reconstructed from tracks and calorimeter towers in pseudorapidity $|\eta| < 1$. We include progress on Bayesian unfolding to correct for detector effects, and show PYTHIA predictions for comparison to the fully corrected data.

Is this an experimental talk? Yes
Is this on behalf of a collaboration? Yes
Which collaboration? STAR
Are you willing to present as a poster if it is not selected for oral presentation? Yes

Author

Emily Pottebaum (Yale University (US))

Presentation materials