Examples of fits to the invariant mass spectra with the hadronic cocktail in pp collisions at √s = 5.02, 8 and 13 TeV, for muon pairs in 2.5 < y < 4. The red histograms represent the sum of all simulated contributions. The correlated continuum has been fitted with a variable-width Gaussian function | ![](https://alice-publications.web.cern.ch/sites/default/files/papers/7058/mass_5TeV_1.png ) ![](https://alice-publications.web.cern.ch/sites/default/files/papers/7058/mass_8TeV_1.png ) ![](https://alice-publications.web.cern.ch/sites/default/files/papers/7058/mass_13TeV_1.png ) |