Figure 2

Direct photon fraction $r$ as a function of $p_{\rm T}$ extracted from fits to dielectron spectra in INEL (left) and HM (right) pp collisions. Statistical and systematic uncertainties of the data are displayed as vertical bars and boxes, respectively. The results in INEL pp collisions are compared to theoretical calculations of Refs. [18] and [35]. The results from HM pp data are compared to theoretical calculations of Ref. [18] for INEL pp collisions scaled by an empirical factor 7 based on Pythia calculations (blue band). The red and green bands show the calculations of Ref. [35] scaled by the factor of 4.5$-$7.5, with the width of the bands representing the range of the applied scaling factor (see the text for more details).