Extended Data Fig. 3: Optimal observables.
From: Determination of the spin and parity of all-charm tetraquarks
Distributions of \({{\mathcal{D}}}_{ij}\) that are optimal for separating the \({2}_{m}^{+}\) model against the \({0}_{m}^{+}\) (upper left), \({0}_{h}^{+}\) (upper right), 1− (lower left), and 1+ (lower right) models in the range 6.2 < m4μ < 8.0 GeV. Distributions for signal only (dashed) and for signal plus background (solid and dash-dot-dotted) models are compared to the experimental data points with error bars, with uncertainty bands representing post-fit model uncertainties, which are partially correlated with the data. The 1− and \({2}_{h}^{-}\) distributions are identical, apart from systematic uncertainties arising from polarization effects. The lower panels display the ratios of the data and of the model predictions to the mean expectations from the \({2}_{m}^{+}\) model.
