Extracted $\Delta$ spectral temperature. The $\Delta$ spectral temperature is derived from $\pi^{\pm}$--p and \piPMd correlation functions measured in high-multiplicity pp collisions at $\sqrt{s} = 13$~TeV. The bands correspond to the uncertainties obtained by fits to the correlation functions, incorporating systematic uncertainties on the measured data, as well as those arising from variations in the source size and the $\lambda$ parameter for the genuine interaction.