Measurement of the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si1.gif" overflow="scroll"><mml:msup><mml:mrow><mml:mi mathvariant="normal">W</mml:mi></mml:mrow><mml:mrow><mml:mo>+</mml:mo></mml:mrow></mml:msup><mml:msup><mml:mrow><mml:mi mathvariant="normal">W</mml:mi></mml:mrow><mml:mrow><mml:mo>−</mml:mo></mml:mrow></mml:msup></mml:math> and ZZ production cross sections in pp collisions at <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si2.gif" overflow="scroll"><mml:msqrt><mml:mi>s</mml:mi></mml:msqrt><mml:mo>=</mml:mo><mml:mn>8</mml:mn><mml:mtext> TeV</mml:mtext></mml:math>

The W+W− and ZZ production cross sections are measured in proton–proton collisions at s=8 TeV with the CMS experiment at the LHC in data samples corresponding to an integrated luminosity of up to 5.3 fb−1. The measurements are performed in the leptonic decay modes W+W−→ℓ′νℓ″ν and ZZ→2ℓ2ℓ′, where ℓ=e,μ and ℓ′(ℓ″)=e,μ,τ. The measured cross sections σ(pp→W+W−)=69.9±2.8(stat.)±5.6(syst.)±3.1(lum.) pb and σ(pp→ZZ)=8.4±1.0(stat.)±0.7(syst.)±0.4(lum.) pb, for both Z bosons produced in the mass region 60<mZ<120 GeV, are consistent with standard model predictions. These are the first measurements of the diboson production cross sections at s=8 TeV.