Measurement of the energy flow in the forward region at the LHC at $\sqrt{s

A measurement is presented of the energy flow in the forward region ($ 3.15<|\eta|< 4.9$, where $\eta$ denotes the pseudorapidity) of the CMS detector at the LHC for centre-of-mass energies $\sqrt{s}$ of 900 GeV, 2360 GeV and 7000 GeV. The energy flow is measured in two different event classes: in minimum bias events and in events with a hard scale provided by a dijet system at central pseudorapidities ($|\eta| < 2.5$) and with transverse energy $E_{T,jet}>8$~GeV at $\sqrt{s}$ of 900 GeV and 2360 GeV and with $E_{T,jet}>20$~GeV at $\sqrt{s}$ of 7000 GeV. The measured forward energy flow is found to be significantly different between the two event classes. The result of the forward energy flow measurement for the two event classes is compared to predictions from Monte Carlo event generators that were tuned to describe the charged particle spectra seen at central rapidities.