Gluon correlations from a Glasma flux-tube model compared to measured hadron correlations on transverse momentum $\bf (p_t,p_t)$ and angular differences $\bf (\eta_\Delta,\phi_\Delta)$

Abstract

A Glasma flux-tube model has been proposed to explain strong elongation on pseudorapidity $\eta$ of the same-side 2D peak in minimum-bias angular correlations from $\sqrt{s_{NN}} = 200$ GeV \auau collisions. The same-side peak or "soft ridge" is said to arise from coupling of flux tubes to radial flow. Gluons radiated transversely from flux tubes are boosted by radial flow to form a narrow structure or ridge on azimuth. In this study we test the conjecture by comparing predictions for particle production, spectra and correlations from the Glasma model and conventional fragmentation processes with measurements. We conclude that the Glasma model is contradicted by measured hadron yields, spectra and correlations, whereas a two-component model of hadron production, including minimum-bias parton fragmentation, provides a quantitative description of most data, although $\eta$ elongation remains unexplained.