Energy loss baseline for light hadrons in oxygen-oxygen collisions at $\sqrt{s_\mathrm{NN}}=5.36\,\text{TeV}$

Abstract

I present predictions for inclusive charged hadron spectra in minimum-bias proton-proton and oxygen-oxygen collisions at a centre-of-mass energy of $\sqrt{s_\mathrm{NN}} = 5.36\,\text{TeV}$, assuming no final-state interactions. Using next-to-leading order perturbative QCD matrix elements, along with state-of-the-art (nuclear) parton distribution and fragmentation functions, I establish a baseline for the nuclear modification factor $R^h_\text{AA}$ in oxygen-oxygen collisions in the absence of quenching. Theoretical uncertainties in this baseline are found to be substantial for transverse momenta below $20\,\text{GeV}$. In the intermediate range $20\,\text{GeV} \lesssim p_T^h \lesssim 70\,\text{GeV}$, these uncertainties are significantly reduced to approximately 5\%. At higher momenta ($p_T^h \gtrsim 70\,\text{GeV}$), however, predictions exhibit a marked spread due to differences between fragmentation functions, reflecting varying assumptions about isospin symmetry. Finally, I show that considering neon-neon collisions in the initial state or neutral pions in the final state does not appreciably change the nuclear modification factor.