Abstract:
The measurement of the energy flow is performed with the forward (HF: 3.15 < vertical bar eta vertical bar < 5.2) and very -forward (CASTOR: 6.6 < eta < 5.2) calorimeters of CMS at the centre-of-mass energy of 13 TeV. The data were taken during the several periods of low luminosity operation in 2015. The results arc compared to Monte Carlo (MC) model predictions as well as the earlier proton proton data taken at root s = 0.9 TeV and 7 TeV. Furthermore, the beam fragmentation which provides valuable input for tuning of MC models used to describe high energy hadronic interactions is also studied at the regions close to the beam rapidities.
