Measurement of charged particle multiplicities and densities in pp collisions at s=7 TeV in the forward region

Charged particle multiplicities are studied in proton–proton collisions in the forward region at a centre-of-mass energy of <math><mrow><msqrt><mi>s</mi></msqrt><mo>=</mo><mn>7</mn><mspace width="0.277778em"/></mrow></math> TeV with data collected by the LHCb detector. The forward spectrometer allows access to a kinematic range of <math><mrow><mn>2.0</mn><mo>&lt;</mo><mi mathvariant="italic">η</mi><mo>&lt;</mo><mn>4.8</mn></mrow></math> in pseudorapidity, momenta greater than <math><mrow><mn>2</mn><mspace width="0.277778em"/><mspace width="0.333333em"/><mtext>GeV/</mtext><mspace width="0.333333em"/><mi>c</mi></mrow></math> and transverse momenta greater than <math><mrow><mn>0.2</mn><mspace width="0.277778em"/><mspace width="0.333333em"/><mtext>GeV/</mtext><mspace width="0.333333em"/><mi>c</mi></mrow></math> . The measurements are performed using events with at least one charged particle in the kinematic acceptance. The results are presented as functions of pseudorapidity and transverse momentum and are compared to predictions from several Monte Carlo event generators.