Measurement of the average very forward energy as a function of the track multiplicity at central pseudorapidities in proton-proton collisions at sqrt(s) = 13 TeV

The average total energy as well as its hadronicand electromagnetic components are measured with the CMSdetector at pseudorapidities−6.6<−5.2 in proton-proton collisions at a centre-of-mass energy√s=13 TeV.The results are presented as a function of the charged par-ticle multiplicity in the region|η|<2. This measurementis sensitive to correlations induced by the underlying eventstructure over a very wide pseudorapidity region. The predic-tions of Monte Carlo event generators commonly used in col-lider experiments and ultra-high energy cosmic ray physicsare compared to the data. All generators considered overes-timate the fraction of energy going into hadrons.