6–10 Jul 2026
University of the Western Cape
Africa/Johannesburg timezone
**Tours now open!** Registration is now closed - All registration payments are due before 23:39 SAST on 26 June.

A pQCD Baseline for Parton and Hadron Production Spectra

9 Jul 2026, 10:10
20m
Lecture Hall DL2 (University of the Western Cape)

Lecture Hall DL2

University of the Western Cape

Oral Presentation Track G - Theoretical and Computational Physics Theoretical and Computational Physics

Speaker

Jack Brand (University of Cape Town)

Description

The quark-gluon plasma (QGP) is a deconfined state of strongly interacting matter that provides a unique laboratory for studying the strong nuclear force. It is produced in relativistic heavy-ion collisions, such as ${}^{208}\mathrm{Pb}+{}^{208}\mathrm{Pb}$ and, more recently, ${}^{16}\mathrm{O}+{}^{16}\mathrm{O}$ at the LHC. High-momentum (“hard”) probes traversing the QGP lose energy through radiative and collisional processes, as described by perturbative quantum chromodynamics (pQCD). A key challenge in interpreting such energy loss signals is the consistent treatment of initial-state effects, which must be understood in order to make reliable predictions for unmeasured collision systems and energies. Within the framework of collinear factorisation, these effects are encoded in parton distribution functions (PDFs), which describe the partonic structure of the incoming nuclei. Here, we present a numerical implementation of the leading-order, $p_T$-differential inclusive production cross section for partons and their fragmentation into hadrons. We validate this framework by reproducing measured charged meson production spectra in proton-proton collisions across a range of centre-of-mass energies. The resulting tool provides a modular framework for computing hadron production spectra for arbitrary fragmentation functions, PDFs, collision systems, and pseudorapidity intervals, including $p_T$ bin averaging. This enables systematic baseline calculations of initial-state contributions to particle production. Combined with energy loss models, this framework allows for quantitative predictions of whether medium-induced modifications to hadron spectra can be disentangled from initial-state effects in small and intermediate collision systems.

Apply for student award at which level: MSc
Consent on use of personal information: Abstract Submission Yes, I ACCEPT

Author

Jack Brand (University of Cape Town)

Co-author

William Horowitz (University of Cape Town)

Presentation materials