Saved in:
Bibliographic Details
Main Author: Yang, Yi
Format: Preprint
Published: 2026
Subjects:
Online Access:https://arxiv.org/abs/2604.11847
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866911593575481344
author Yang, Yi
author_facet Yang, Yi
contents The suppression of heavy quarkonium polarization at high transverse momentum ($p_T$) remains a persistent puzzle in quantum chromodynamics (QCD). We propose an effective open-quantum-system paradigm demonstrating that the heavy quark spin state and its macroscopic momentum effectively decouple during hadronization. By retaining the short-distance non-relativistic QCD (NRQCD) perturbative calculations as a kinematic baseline, we argue that the immense kinematic inertia at high $p_T$ parametrically preserves the power-law momentum spectrum. Concurrently, the intense, stochastic chromo-electric background within a fragmenting jet acts as a dynamic decoherence environment. Using a horizon-inspired picture as a physically motivated parametrization, we derive an effective temperature $T_{\text{eff}}(z) \propto \sqrt{\ln(1/z)}$ driven by the multiplicity of soft accompanying partons. By incorporating this effective temperature into a Lindblad dissipation framework, we predict a simultaneous quenching of the polar and azimuthal anisotropies towards a maximally mixed state. Crucially, the recently observed ``soft'' fragmentation of $Υ(nS)$ by the CMS Collaboration provides a highly consistent phase-space weighting required in our framework to explain the historical inclusive unpolarized anomaly. Identifying the fragmentation fraction $z=p_T^{\mathcal{Q}}/p_T^{\text{jet}}$ as the critical control variable, we propose that a key testable prediction is the simultaneous $z$-dependent suppression of $λ_θ$, $λ_ϕ$, and $\tildeλ$ in fixed quarkonium and jet $p_T$ bins.
format Preprint
id arxiv_https___arxiv_org_abs_2604_11847
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Spin-Momentum Decoupling in Quarkonium Hadronization: Polarization Quenching via Environment-Induced Decoherence in Jets
Yang, Yi
High Energy Physics - Phenomenology
High Energy Physics - Experiment
The suppression of heavy quarkonium polarization at high transverse momentum ($p_T$) remains a persistent puzzle in quantum chromodynamics (QCD). We propose an effective open-quantum-system paradigm demonstrating that the heavy quark spin state and its macroscopic momentum effectively decouple during hadronization. By retaining the short-distance non-relativistic QCD (NRQCD) perturbative calculations as a kinematic baseline, we argue that the immense kinematic inertia at high $p_T$ parametrically preserves the power-law momentum spectrum. Concurrently, the intense, stochastic chromo-electric background within a fragmenting jet acts as a dynamic decoherence environment. Using a horizon-inspired picture as a physically motivated parametrization, we derive an effective temperature $T_{\text{eff}}(z) \propto \sqrt{\ln(1/z)}$ driven by the multiplicity of soft accompanying partons. By incorporating this effective temperature into a Lindblad dissipation framework, we predict a simultaneous quenching of the polar and azimuthal anisotropies towards a maximally mixed state. Crucially, the recently observed ``soft'' fragmentation of $Υ(nS)$ by the CMS Collaboration provides a highly consistent phase-space weighting required in our framework to explain the historical inclusive unpolarized anomaly. Identifying the fragmentation fraction $z=p_T^{\mathcal{Q}}/p_T^{\text{jet}}$ as the critical control variable, we propose that a key testable prediction is the simultaneous $z$-dependent suppression of $λ_θ$, $λ_ϕ$, and $\tildeλ$ in fixed quarkonium and jet $p_T$ bins.
title Spin-Momentum Decoupling in Quarkonium Hadronization: Polarization Quenching via Environment-Induced Decoherence in Jets
topic High Energy Physics - Phenomenology
High Energy Physics - Experiment
url https://arxiv.org/abs/2604.11847