Measurements of differential jet cross sections in proton-proton collisions at $\sqrt{s}\mathbf{=}7\mathrm{TeV}$ with the CMS detector

Measurements of inclusive jet and dijet production cross sections are presented. Data from LHC proton-proton collisions at $\sqrt{s}=7\mathrm{TeV}$, corresponding to $5.0{\mathrm{fb}}^{-1}$ of integrated luminosity, have been collected with the CMS detector. Jets are reconstructed up to rapidity 2.5, transverse momentum 2 TeV, and dijet invariant mass 5 TeV, using the anti-$k_{\mathrm{T}}$ clustering algorithm with distance parameter $R=0.7$. The measured cross sections are corrected for detector effects and compared to perturbative QCD predictions at next-to-leading order, using five sets of parton distribution functions.

Figure 1

Trigger efficiency as a function of the jet $p_{\mathrm{T}}$ (top) and dijet mass $M_{\mathrm{jj}}$ (bottom) for the 370 GeV single-jet trigger and for the central rapidity bins.

Figure 2

Distribution of $F_{\mathrm{T}}^{\mathrm{miss}}/\Sigma E_{\mathrm{T}}$ for data events (black points) and simulated QCD events (continuous line) with at least one jet with $p_{\mathrm{T}}>510\mathrm{GeV}$ (top) and for dijet events with $|y{|}_{\max }<2.5$ and $M_{\mathrm{jj}}>910\mathrm{GeV}$ (bottom), collected with the 370 GeV single-jet trigger. The distribution from the inclusive jet selection is shown before the offline selection $E_{\mathrm{T}}^{\mathrm{miss}}/\Sigma E_{\mathrm{T}}<0.3$. The larger tail in the data is caused by other processes with true $E_{\mathrm{T}}^{\mathrm{miss}}$ [such as $Z+\mathrm{\text{jet}}(\mathrm{s})$, where the $Z$ boson decays to neutrinos, and $W+\mathrm{\text{jet}}(\mathrm{s})$, where the $W$ boson decays to leptons].

Figure 3

Spectrum construction from individual trigger paths. Top: inclusive jet $p_{\mathrm{T}}$ spectrum for $|y|<0.5$. Bottom: dijet mass spectrum for $|y{|}_{\max }<0.5$. The different markers indicate different trigger paths.

Figure 4

Response matrices for the inclusive jet $p_{\mathrm{T}}$ spectrum (top) and the dijet mass spectrum (bottom) in the central rapidity bins.

Figure 5

Effect of the relative experimental uncertainties for the inclusive jet (left column) and dijet (right column) cross section measurements, and for all five $|y|$ and $|y{|}_{\max }$ bins, respectively. The upward and downward uncertainties are estimated separately.

Figure 6

Effect of the relative theoretical uncertainties for the inclusive jet (left column) and dijet (right column) cross section measurements for all five $|y|$ and $|y{|}_{\max }$ bins, respectively. The upward and downward uncertainties are estimated separately.

Figure 7

Inclusive jet (top) and dijet (bottom) cross sections for the five different rapidity bins, for data (markers) and theory (thick lines) using the NNPDF2.1 PDF set.

Figure 8

Ratio of inclusive jet (left) and dijet (right) cross sections to the theoretical prediction using the central value of the NNPDF2.1 PDF set for the first three $|y|$ and $|y{|}_{\max }$ bins, respectively. The solid histograms show the ratio of the cross sections calculated with the other PDF sets to that calculated with NNPDF2.1. The experimental and theoretical systematic uncertainties are represented by the continuous and hatched bands, respectively.

Figure 9

Ratio of inclusive jet (left) and dijet (right) cross sections to the theoretical prediction using the central value of the NNPDF2.1 PDF set for the last two $|y|$ and $|y{|}_{\max }$ bins, respectively. The solid histograms show the ratio of the cross sections calculated with the other PDF sets to that calculated with NNPDF2.1. The experimental and theoretical systematic uncertainties are represented by the continuous and hatched bands, respectively.