A measurement of event-shape variables is presented, using a data sample produced in a special run with
approximately one inelastic proton-proton collision per bunch crossing. The data were collected with the
CMS detector at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 64 μb−1.
A number of observables related to the overall distribution of charged particles in the collisions are
corrected for detector effects and compared with simulations. Inclusive event-shape distributions, as well as
differential distributions of event shapes as functions of charged-particle multiplicity, are studied. None of
the models investigated are able to satisfactorily describe the data. Moreover, there are significant features
common amongst all generator setups studied, particularly showing data being more isotropic than any of
the simulations. Multidimensional unfolded distributions are provided, along with their correlations.
