Flattenicity dependence of charge and transverse-momentum balance functions in pp collisions at √s=13.6 TeV with PYTHIA8
Abstract
We study the charge balance function B(Δη,Δϕ) and the charge-dependent transverse-momentum balance function P2CD(Δη,Δϕ) in proton--proton (pp) collisions at √s=13.6~TeV using \texttt{PYTHIA~8.315} with the Monash tune. Flattenicity is employed as an event-shape observable to probe how these correlations depend on the topology of particle production. The results are examined across different charged-particle multiplicity intervals to disentangle the effects of overall event activity and event topology on B and P2CD. Both observables exhibit pronounced near-side correlations around (Δη,Δϕ)≈(0,0). The near-side peaks become stronger with increasing charged-particle multiplicity, and the RMS widths of both observables decrease systematically, indicating that the correlations become more localized in relative pseudorapidity and azimuth. A clear dependence on flattenicity is also observed: jet-like events (low flattenicity) generally exhibit stronger and narrower near-side correlations than isotropic events (high flattenicity). This event-shape dependence is more pronounced for P2CD than for B, indicating that P2CD is more sensitive to event topology, whereas B primarily probes charge-dependent particle-pair correlations. These results demonstrate the complementary nature of the two observables and the potential of flattenicity-based event selection for studying particle-production mechanisms in high-multiplicity pp collisions.
Related
- Measurement of the average transverse momentum of forward prompt charged particles in pp and pPb collisions at √(sNN) = 5.02 TeV
- Comment on "Non-Monotonicity of Transverse-Momentum Correlations in Au+Au Collisions at RHIC"
- Search for supersymmetric particle pair production in final states with two oppositely charged leptons and large missing transverse momentum in proton-proton collisions at √s = 13 TeV
- Final-state effects on the transverse-momentum spectra of charged hadrons in p+Pb and Pb+Pb collisions at √(sNN) = 5.02~TeV using the modified Tsallis distribution
- Search for a leptoquark in events with a hadronically decaying τ-lepton and missing transverse momentum using pp collisions at s=13TeV with the ATLAS detector
BibTeX
@misc{roy2026flattenicity,
title = {{Flattenicity dependence of charge and transverse-momentum balance functions in $pp$ collisions at $\sqrts=13.6$ TeV with PYTHIA8}},
author = {Srabani Dutta Roy and Rohit Agarwala and Kalyan Dey},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.26058},
eprint = {2610.26058},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.26058},
note = {CC BY-NC-ND 4.0},
}
RIS
TY - UNPB
TI - Flattenicity dependence of charge and transverse-momentum balance functions in pp collisions at √s=13.6 TeV with PYTHIA8
AU - Srabani Dutta Roy
AU - Rohit Agarwala
AU - Kalyan Dey
PY - 2026
DA - 2026/10/19
PB - arXiv
DO - 10.48550/arxiv.2610.26058
UR - https://arxiv.org/abs/2610.26058
AB - We study the charge balance function B(Δη,Δϕ) and the charge-dependent transverse-momentum balance function P_2^CD(Δη,Δϕ) in proton--proton (pp) collisions at √s=13.6~TeV using \texttt{PYTHIA~8.315} with the Monash tune. Flattenicity is employed as an event-shape observable to probe how these correlations depend on the topology of particle production. The results are examined across different charged-particle multiplicity intervals to disentangle the effects of overall event activity and event topology on B and P_2^CD. Both observables exhibit pronounced near-side correlations around (Δη,Δϕ)≈(0,0). The near-side peaks become stronger with increasing charged-particle multiplicity, and the RMS widths of both observables decrease systematically, indicating that the correlations become more localized in relative pseudorapidity and azimuth. A clear dependence on flattenicity is also observed: jet-like events (low flattenicity) generally exhibit stronger and narrower near-side correlations than isotropic events (high flattenicity). This event-shape dependence is more pronounced for P_2^CD than for B, indicating that P_2^CD is more sensitive to event topology, whereas B primarily probes charge-dependent particle-pair correlations. These results demonstrate the complementary nature of the two observables and the potential of flattenicity-based event selection for studying particle-production mechanisms in high-multiplicity pp collisions.
ER -