Charged particle transverse momentum spectra in $pp$ collisions at $\sqrt{s} = 0.9$ and 7 TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
JHEP 08 (2011) 086, 2011.
Inspire Record 896764 DOI 10.17182/hepdata.57523

The charged particle transverse momentum (pT) spectra are presented for pp collisions at sqrt(s)=0.9 and 7 TeV. The data samples were collected with the CMS detector at the LHC and correspond to integrated luminosities of 231 inverse microbarns and 2.96 inverse picobarns, respectively. Calorimeter-based high-transverse-energy triggers are employed to enhance the statistical reach of the high-pT measurements. The results are compared with both leading-order QCD and with an empirical scaling of measurements at different collision energies using the scaling variable xT = 2 pT/sqrt(s) over the pT range up to 200 GeV/c. Using a combination of xT scaling and direct interpolation at fixed pT, a reference transverse momentum spectrum at sqrt(s)=2.76 TeV is constructed, which can be used for studying high-pT particle suppression in the dense QCD medium produced in heavy-ion collisions at that centre-of-mass energy.

5 data tables

The invariant charged particle differential yield at 0.9 TeV for |eta|<2.4.

The invariant charged particle differential yield at 7 TeV for |eta|<2.4.

The inclusive charged particle invariant differential cross section, as a function of XT and scaled by sqrt(s)*4.9, at 0.9 TeV for |eta|<1.

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Measurement of the differential dijet production cross section in proton-proton collisions at $\sqrt{s}=7$ TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
Phys.Lett.B 700 (2011) 187-206, 2011.
Inspire Record 895742 DOI 10.17182/hepdata.58935

A measurement of the double-differential inclusive dijet production cross section in proton-proton collisions at sqrt(s)=7 TeV is presented as a function of the dijet invariant mass and jet rapidity. The data correspond to an integrated luminosity of 36 inverse picobarns, recorded with the CMS detector at the LHC. The measurement covers the dijet mass range 0.2 TeV to 3.5 TeV and jet rapidities up to |y|=2.5. It is found to be in good agreement with next-to-leading-order QCD predictions.

5 data tables

The double differential cross section as a function of the di-jet mass for the range |y_max| = 0.0-0.5, where |y_max| = max(|y1,|y2|) of the two leading jets in the event.

The double differential cross section as a function of the di-jet mass for the range |y_max| = 0.5-1.0, where |y_max| = max(|y1,|y2|) of the two leading jets in the event.

The double differential cross section as a function of the di-jet mass for the range |y_max| = 1.0-1.5, where |y_max| = max(|y1,|y2|) of the two leading jets in the event.

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Search for Supersymmetry in $pp$ Collisions at $\sqrt{s} = 7$ TeV in Events with Two Photons and Missing Transverse Energy

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
Phys.Rev.Lett. 106 (2011) 211802, 2011.
Inspire Record 891482 DOI 10.17182/hepdata.57149

A search for supersymmetry in the context of general gauge-mediated (GGM) breaking with the lightest neutralino as the next-to-lightest supersymmetric particle and the gravitino as the lightest is presented. The data sample corresponds to an integrated luminosity of 36 inverse picobarns recorded by the CMS experiment at the LHC. The search is performed using events containing two or more isolated photons, at least one hadronic jet, and significant missing transverse energy. No excess of events at high missing transverse energy is observed. Upper limits on the signal cross section for GGM supersymmetry between 0.3 and 1.1 pb at the 95% confidence level are determined for a range of squark, gluino, and neutralino masses, excluding supersymmetry parameter space that was inaccessible to previous experiments.

66 data tables

95 PCT CL upper limits to cross section and the GGM acceptance as a function of Gluino mass for Squark mass 400 GeV and Neutralino mass 50 GeV.

95 PCT CL upper limits to cross section and the GGM acceptance as a function of Gluino mass for Squark mass 480 GeV and Neutralino mass 50 GeV.

95 PCT CL upper limits to cross section and the GGM acceptance as a function of Gluino mass for Squark mass 560 GeV and Neutralino mass 50 GeV.

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Measurement of $B\bar{B}$ Angular Correlations based on Secondary Vertex Reconstruction at $\sqrt{s}=7$ TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M. ; Tumasyan, Armen ; et al.
JHEP 03 (2011) 136, 2011.
Inspire Record 889807 DOI 10.17182/hepdata.57695

A measurement of the angular correlations between beauty and anti-beauty hadrons (B B-bar) produced in pp collisions at a centre-of-mass energy of 7 TeV at the CERN LHC is presented, probing for the first time the region of small angular separation. The B hadrons are identified by the presence of displaced secondary vertices from their decays. The B hadron angular separation is reconstructed from the decay vertices and the primary-interaction vertex. The differential B B-bar production cross section, measured from a data sample collected by CMS and corresponding to an integrated luminosity of 3.1 inverse picobarns, shows that a sizable fraction of the B B-bar pairs are produced with small opening angles. These studies provide a test of QCD and further insight into the dynamics of b b-bar production.

6 data tables

Cross section as a function of DELTA(R) for leading jet transverse momentum > 56 GeV. . The (sys) error in the table is due to the limited MC statistics and is uncorrelated bin-to-bin. The other two systematic errors are correlated.

Cross section as a function of DELTA(R) for leading jet transverse momentum > 84 GeV. . The (sys) error in the table is due to the limited MC statistics and is uncorrelated bin-to-bin. The other two systematic errors are correlated.

Cross section as a function of DELTA(R) for leading jet transverse momentum > 120 GeV. . The (sys) error in the table is due to the limited MC statistics and is uncorrelated bin-to-bin. The other two systematic errors are correlated. Note that these two systematic errors are different for the final point.

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Measurement of $W^+ W^-$ production and search for the Higgs boson in pp collisions at $\sqrt s=7$ TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
Phys.Lett.B 699 (2011) 25-47, 2011.
Inspire Record 890910 DOI 10.17182/hepdata.57953

A measurement of WW production in pp collisions at sqrt(s) = 7 TeV and a search for the Higgs boson are reported. The WW candidates are selected in events with two leptons, either electrons or muons. The measurement is performed using LHC data recorded with the CMS detector, corresponding to an integrated luminosity of 36 inverse picobarns. The pp to WW cross section is measured to be 41.1 +/- 15.3 (stat) +/- 5.8 (syst) +/- 4.5 (lumi) pb, consistent with the standard model prediction. Limits on WW gamma and WWZ anomalous triple gauge couplings are set. The search for the standard model Higgs boson in the WW decay mode does not reveal any evidence of excess above backgrounds. Limits are set on the production of the Higgs boson in the context of the standard model and in the presence of a sequential fourth family of fermions with high masses. In the latter context, a Higgs boson with mass between 144 and 207 GeV is ruled out at 95% confidence level.

1 data table

The measured W+ W- cross section.


Measurement of Dijet Angular Distributions and Search for Quark Compositeness in pp Collisions at $sqrt{s} = 7$ TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M. ; Tumasyan, Armen ; et al.
Phys.Rev.Lett. 106 (2011) 201804, 2011.
Inspire Record 889175 DOI 10.17182/hepdata.57092

Dijet angular distributions are measured over a wide range of dijet invariant masses in pp collisions at sqrt(s) = 7 TeV, at the CERN LHC. The event sample, recorded with the CMS detector, corresponds to an integrated luminosity of 36 inverse picobarns. The data are found to be in good agreement with the predictions of perturbative QCD, and yield no evidence of quark compositeness. With a modified frequentist approach, a lower limit on the contact interaction scale for left-handed quarks of Lambda = 5.6 TeV (6.7 TeV) for destructive (constructive) interference is obtained at the 95% confidence level.

9 data tables

Normalized dijet angular distribution for the dijet mass range > 2200 GeV.

Normalized dijet angular distribution for the dijet mass range 1800 to 2200 GeV.

Normalized dijet angular distribution for the dijet mass range 1400 to 1800 GeV.

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Strange Particle Production in $pp$ Collisions at $\sqrt{s}=0.9$ and 7 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
JHEP 05 (2011) 064, 2011.
Inspire Record 890166 DOI 10.17182/hepdata.57531

The spectra of strange hadrons are measured in proton-proton collisions, recorded by the CMS experiment at the CERN LHC, at centre-of-mass energies of 0.9 and 7 TeV. The K^0_s, Lambda, and Xi^- particles and their antiparticles are reconstructed from their decay topologies and the production rates are measured as functions of rapidity and transverse momentum. The results are compared to other experiments and to predictions of the PYTHIA Monte Carlo program. The transverse momentum distributions are found to differ substantially from the PYTHIA results and the production rates exceed the predictions by up to a factor of three.

15 data tables

The rapidity production spectra per NSD event spectra for KS mesons at 0.9 and 7 TeV.

The transverse momentum production spectra per NSD event spectra for KS mesons at 0.9 and 7 TeV.

The rapidity production spectra per NSD event spectra for LAMBDA mesons at 0.9 and 7 TeV.

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Study of Z boson production in PbPb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
Phys.Rev.Lett. 106 (2011) 212301, 2011.
Inspire Record 890909 DOI 10.17182/hepdata.57943

A search for Z bosons in the mu^+mu^- decay channel has been performed in PbPb collisions at a nucleon-nucleon centre of mass energy = 2.76 TeV with the CMS detector at the LHC, in a 7.2 inverse microbarn data sample. The number of opposite-sign muon pairs observed in the 60--120 GeV/c2 invariant mass range is 39, corresponding to a yield per unit of rapidity (y) and per minimum bias event of (33.8 ± 5.5 (stat) ± 4.4 (syst)) 10^{-8}, in the |y|<2.0 range. Rapidity, transverse momentum, and centrality dependencies are also measured. The results agree with next-to-leading order QCD calculations, scaled by the number of incoherent nucleon-nucleon collisions.

4 data tables

The dimuon yield from Z0 decays per unit rapidity and per unit minumum bias event in the range |yrap| < 2.0.

The dimuon yield from Z0 decays per unit rapidity and per unit minumum bias event as a function of rapidity, and the nuclear modification factor RAA derived by using a POWHEG proton-proton reference.

The dimuon yield from Z0 decays per unit rapidity and per unit minumum bias event as a function of transverse momentum, and the nuclear modificationfactor RAA derived by using a POWHEG proton-proton reference.

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First Measurement of Hadronic Event Shapes in $pp$ Collisions at $\sqrt {s}=7$ TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M. ; Tumasyan, Armen ; et al.
Phys.Lett.B 699 (2011) 48-67, 2011.
Inspire Record 886332 DOI 10.17182/hepdata.63817

Hadronic event shapes have been measured in proton-proton collisions at sqrt(s)=7 TeV, with a data sample collected with the CMS detector at the LHC. The sample corresponds to an integrated luminosity of 3.2 inverse picobarns. Event-shape distributions, corrected for detector response, are compared with five models of QCD multijet production.

6 data tables

Distribution of the logarithm of the central transverse thrust for events with jet transverse momentum > 30 GeV, jet |pseudorapidity| < 1.3 and leading the jet transverse momentum from 90 to 125 GeV/c,.

Distribution of the logarithm of the central thrust minor for events with jet transverse momentum > 30 GeV, jet |pseudorapidity| < 1.3 and leading the jet transverse momentum from 90 to 125 GeV/c,.

Distribution of the logarithm of the central transverse thrust for events with jet transverse momentum > 30 GeV, jet |pseudorapidity| < 1.3 and leading the jet transverse momentum from 125 to 200 GeV/c,.

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Inclusive b-Hadron Production Cross Section with Muons in $pp$ Collisions at $\sqrt{s} = 7$ TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M. ; Tumasyan, Armen ; et al.
JHEP 03 (2011) 090, 2011.
Inspire Record 884811 DOI 10.17182/hepdata.57723

A measurement of the b-hadron production cross section in proton-proton collisions at sqrt(s)=7 TeV is presented. The dataset, corresponding to 85 inverse nanobarns, was recorded with the CMS experiment at the LHC using a low-threshold single-muon trigger. Events are selected by the presence of a muon with transverse momentum greater than 6 GeV with respect to the beam direction and pseudorapidity less than 2.1. The transverse momentum of the muon with respect to the closest jet discriminates events containing b hadrons from background. The inclusive b-hadron production cross section is presented as a function of muon transverse momentum and pseudorapidity. The measured total cross section in the kinematic acceptance is sigma(pp to b+X to mu + X') =1.32 +/- 0.01 (stat) +/- 0.30 (syst) +/- 0.15 (lumi) microbarns.

3 data tables

Total inclusive cross section in the visible kinematic range.

Muon transverse momentum differential distibution.

Muon pseudorapidity differential distibution.


Dijet Azimuthal Decorrelations in $pp$ Collisions at $\sqrt{s} = 7$~TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M. ; Tumasyan, Armen ; et al.
Phys.Rev.Lett. 106 (2011) 122003, 2011.
Inspire Record 885663 DOI 10.17182/hepdata.57051

Measurements of dijet azimuthal decorrelations in pp collisions at sqrt(s) = 7 TeV using the CMS detector at the CERN LHC are presented. The analysis is based on an inclusive dijet event sample corresponding to an integrated luminosity of 2.9 inverse picobarns. The results are compared to predictions from perturbative QCD calculations and various Monte Carlo event generators. The dijet azimuthal distributions are found to be sensitive to initial-state gluon radiation.

5 data tables

Normalized Delta_Phi distributions for events with a maximum jet pT between 80 and 110 GeV.

Normalized Delta_Phi distributions for events with a maximum jet pT between 110 and 140 GeV.

Normalized Delta_Phi distributions for events with a maximum jet pT between 140 and 200 GeV.

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Measurement of the $B^+$ Production Cross Section in pp Collisions at $\sqrt{s} = 7$~TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M. ; Tumasyan, Armen ; et al.
Phys.Rev.Lett. 106 (2011) 112001, 2011.
Inspire Record 883318 DOI 10.17182/hepdata.57687

Measurements of the total and differential cross sections with respect to transverse momentum and rapidity for B+ mesons produced in pp collisions at sqrt(s) = 7 TeV are presented. The data correspond to an integrated luminosity of 5.8 inverse picobarns collected by the CMS experiment operating at the LHC. The exclusive decay B+ to J/psi K+, with the J/psi decaying to an oppositely charged muon pair, is used to detect B+ mesons and to measure the production cross section as a function of the transverse momentum and rapidity of the B. The total cross section for p_t(B) > 5 GeV and |y(B)| < 2.4 is measured to be 28.1 +/- 2.4 +/- 2.0 +/- 3.1 microbarns, where the first uncertainty is statistical, the second is systematic, and the last is from the luminosity measurement.

3 data tables

Total integrated cross section in the given kinematic range. The (sys) error includes the uncertainty in the branching fraction.

Measured differential cross section as a function of the transverse momentum of the B+ particle.

Measured differential cross section as a function of the rapidity of the B+ particle.


Measurement of Bose-Einstein Correlations in $pp$ Collisions at $\sqrt{s}=0.9$ and 7 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M. ; Tumasyan, Armen ; et al.
JHEP 05 (2011) 029, 2011.
Inspire Record 884808 DOI 10.17182/hepdata.60018

Bose-Einstein correlations between identical particles are measured in samples of proton-proton collisions at 0.9 and 7 TeV centre-of-mass energies, recorded by the CMS experiment at the LHC. The signal is observed in the form of an enhancement of number of pairs of same-sign charged particles with small relative momentum. The dependence of this enhancement on kinematic and topological features of the event is studied.

7 data tables

The double ratio R_double at 900 and 7000 GeV.

The double ratio R_double at 7000 GeV in different bins of charged particle multiplicity and kT.

The double ratio R_double at 7000 GeV in different bins of charged particle multiplicity and kT.

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Measurement of the Isolated Prompt Photon Production Cross Section in $pp$ Collisions at $\sqrt{s} = 7$~TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M. ; Tumasyan, Armen ; et al.
Phys.Rev.Lett. 106 (2011) 082001, 2011.
Inspire Record 879403 DOI 10.17182/hepdata.63810

The differential cross section for the inclusive production of isolated prompt photons has been measured as a function of the photon transverse energy E_T-gamma in pp collisions at sqrt(s)=7 TeV using data recorded by the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 2.9 inverse picobarns. Photons are required to have a pseudorapidity |eta_gamma|<1.45 and E_T-gamma > 21 GeV, covering the kinematic region 0.006 < x_T < 0.086. The measured cross section is found to be in agreement with next-to-leading-order perturbative QCD calculations.

1 data table

Measured isolated prompt photon differential cross section.


Upsilon Production Cross-Section in pp Collisions at $\sqrt{s}$=7 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M. ; Tumasyan, Armen ; et al.
Phys.Rev.D 83 (2011) 112004, 2011.
Inspire Record 882871 DOI 10.17182/hepdata.57722

The Upsilon production cross section in proton-proton collisions at sqrt(s) = 7 TeV is measured using a data sample collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 3.1 +/- 0.3 inverse picobarns. Integrated over the rapidity range |y|<2, we find the product of the Upsilon(1S) production cross section and branching fraction to dimuons to be sigma(pp to Upsilon(1S) X) B(Upsilon(1S) to mu+ mu-) = 7.37 +/- 0.13^{+0.61}_{-0.42}\pm 0.81 nb, where the first uncertainty is statistical, the second is systematic, and the third is associated with the estimation of the integrated luminosity of the data sample. This cross section is obtained assuming unpolarized Upsilon(1S) production. If the Upsilon(1S) production polarization is fully transverse or fully longitudinal the cross section changes by about 20%. We also report the measurement of the Upsilon(1S), Upsilon(2S), and Upsilon(3S) differential cross sections as a function of transverse momentum and rapidity.

15 data tables

Production cross sections integrated over the range |eta| < 2 and PT < 30 GeV. The second systematic error is the uncertainty on the luminosity.

UPSI(1S) differential cross sections for |y| < 2.

UPSI(2S) differential cross sections for |y| < 2.

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Measurements of Inclusive $W$ and $Z$ Cross Sections in $pp$ Collisions at $\sqrt{s}=7$ TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M. ; Tumasyan, Armen ; et al.
JHEP 01 (2011) 080, 2011.
Inspire Record 881087 DOI 10.17182/hepdata.57952

Measurements of inclusive W and Z boson production cross sections in pp collisions at sqrt(s)=7 TeV are presented, based on 2.9 inverse picobarns of data recorded by the CMS detector at the LHC. The measurements, performed in the electron and muon decay channels, are combined to give sigma(pp to WX) times B(W to muon or electron + neutrino) = 9.95 \pm 0.07(stat.) \pm 0.28(syst.) \pm 1.09(lumi.) nb and sigma(pp to ZX) times B(Z to oppositely charged muon or electron pairs) = 0.931 \pm 0.026(stat.) \pm 0.023(syst.) \pm 0.102(lumi.) nb. Theoretical predictions, calculated at the next-to-next-to-leading order in QCD using recent parton distribution functions, are in agreement with the measured cross sections. Ratios of cross sections, which incur an experimental systematic uncertainty of less than 4%, are also reported.

8 data tables

Measured cross sections for combined positive and negative W production.

Measured cross sections for positive W production.

Measured cross sections for negative W production.

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Prompt and Non-Prompt $J/\psi$ Production in $pp$ Collisions at $\sqrt{s}=7$ TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Eur.Phys.J.C 71 (2011) 1575, 2011.
Inspire Record 878118 DOI 10.17182/hepdata.57532

The production of J/psi mesons is studied in pp collisions at sqrt(s)=7 TeV with the CMS experiment at the LHC. The measurement is based on a dimuon sample corresponding to an integrated luminosity of 314 inverse nanobarns. The J/psi differential cross section is determined, as a function of the J/psi transverse momentum, in three rapidity ranges. A fit to the decay length distribution is used to separate the prompt from the non-prompt (b hadron to J/psi) component. Integrated over J/psi transverse momentum from 6.5 to 30 GeV/c and over rapidity in the range |y| < 2.4, the measured cross sections, times the dimuon decay branching fraction, are 70.9 \pm 2.1 (stat.) \pm 3.0 (syst.) \pm 7.8(luminosity) nb for prompt J/psi mesons assuming unpolarized production and 26.0 \pm 1.4 (stat.) \pm 1.6 (syst.) \pm 2.9 (luminosity) nb for J/psi mesons from b-hadron decays.

13 data tables

Total cross section within the kinematic limits for prompt and non-prompt J/PSI production times branching ratio into MU+ MU-, assuming zero polarizartion. The second systematic error is the luminosity uncertainty.

Differential inclusive cross J/PSI section for the |rapidity| range 0 to 1.2 for each prompt J/PSI polarization scenario considered.

Differential inclusive cross J/PSI section for the |rapidity| range 1.2 to 1.6 for each prompt J/PSI polarization scenario considered.

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Charged Particle Multiplicities in $pp$ Interactions at $\sqrt{s}=0.9$, 2.36, and 7 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M. ; Tumasyan, Armen ; et al.
JHEP 01 (2011) 079, 2011.
Inspire Record 879315 DOI 10.17182/hepdata.57909

Measurements of primary charged hadron multiplicity distributions are presented for non-single-diffractive events in proton-proton collisions at centre-of-mass energies of sqrt(s) = 0.9, 2.36, and 7 TeV, in five pseudorapidity ranges from |eta|<0.5 to |eta|<2.4. The data were collected with the minimum-bias trigger of the CMS experiment during the LHC commissioning runs in 2009 and the 7 TeV run in 2010. The multiplicity distribution at sqrt(s) = 0.9 TeV is in agreement with previous measurements. At higher energies the increase of the mean multiplicity with sqrt(s) is underestimated by most event generators. The average transverse momentum as a function of the multiplicity is also presented. The measurement of higher-order moments of the multiplicity distribution confirms the violation of Koba-Nielsen-Olesen scaling that has been observed at lower energies.

29 data tables

Mean multiplicity for charged hadron production for |pseudorapidity| < 2.4.

Fully corrected charged hadron multiplicity spectrum for |pseudorapidity| < 0.5 at a centre-of-mass energy of 900 GeV.

Fully corrected charged hadron multiplicity spectrum for |pseudorapidity| < 1.0 at a centre-of-mass energy of 900 GeV.

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Search for Dijet Resonances in 7 TeV pp Collisions at CMS

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M. ; Tumasyan, Armen ; et al.
Phys.Rev.Lett. 105 (2010) 211801, 2010.
Inspire Record 871540 DOI 10.17182/hepdata.56737

A search for narrow resonances in the dijet mass spectrum is performed using data corresponding to an integrated luminosity of 2.9 inverse pb collected by the CMS experiment at the LHC. Upper limits at the 95% confidence level (CL) are presented on the product of the resonance cross section, branching fraction into dijets, and acceptance, separately for decays into quark-quark, quark-gluon, or gluon-gluon pairs. The data exclude new particles predicted in the following models at the 95% CL: string resonances, with mass less than 2.50 TeV, excited quarks, with mass less than 1.58 TeV, and axigluons, colorons, and E_6 diquarks, in specific mass intervals. This extends previously published limits on these models.

2 data tables

Dijet mass spectrum. As this data is uncorrected for detector effects it is not tabulated here.

95% CL upper limits for dijet resonances for an acceptance value (A) of 0.6.


First Measurement of the Cross Section for Top-Quark Pair Production in Proton-Proton Collisions at $\sqrt{s}=7$ TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M. ; Tumasyan, Armen ; et al.
Phys.Lett.B 695 (2011) 424-443, 2011.
Inspire Record 874738 DOI 10.17182/hepdata.63811

The first measurement of the cross section for top-quark pair production in pp collisions at the LHC at center-of-mass energy sqrt(s)= 7 TeV has been performed using 3.1 {\pm} 0.3 inverse pb of data recorded by the CMS detector. This result utilizes the final state with two isolated, highly energetic charged leptons, large missing transverse energy, and two or more jets. Backgrounds from Drell-Yan and non-W/Z boson production are estimated from data. Eleven events are observed in the data with 2.1 {\pm} 1.0 events expected from background. The measured cross section is 194 {\pm} 72 (stat.) {\pm} 24 (syst.) {\pm} 21 (lumi.) pb, consistent with next-to-leading order predictions.

1 data table

Total cross section. The second systematic error represents the uncertainty on the luminosity.


Transverse-momentum and pseudorapidity distributions of charged hadrons in $pp$ collisions at $\sqrt{s}=7$ TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M. ; Tumasyan, Armen ; et al.
Phys.Rev.Lett. 105 (2010) 022002, 2010.
Inspire Record 855299 DOI 10.17182/hepdata.56006

Charged-hadron transverse-momentum and pseudorapidity distributions in proton-proton collisions at sqrt(s) = 7 TeV are measured with the inner tracking system of the CMS detector at the LHC. The charged-hadron yield is obtained by counting the number of reconstructed hits, hit-pairs, and fully reconstructed charged-particle tracks. The combination of the three methods gives a charged-particle multiplicity per unit of pseudorapidity, dN(charged)/d(eta), for |eta| < 0.5, of 5.78 +/- 0.01 (stat) +/- 0.23 (syst) for non-single-diffractive events, higher than predicted by commonly used models. The relative increase in charged-particle multiplicity from sqrt(s) = 0.9 to 7 TeV is 66.1% +/- 1.0% (stat) +/- 4.2% (syst). The mean transverse momentum is measured to be 0.545 +/- 0.005 (stat) +/- 0.015 (syst) GeV/c. The results are compared with similar measurements at lower energies.

5 data tables

Measured differential yield of charged hadrons as a function oftransverse momentum for pseudorapidities 0.1, 0.3, 0.5 and 0.7 for centre-of-mass energy 7000 GeV.Errors are statistical and systematic added in quadrature.

Measured differential yield of charged hadrons as a function oftransverse momentum for pseudorapidities 0.9, 1.1, 1.3 and 1.5 for centre-of-mass energy 7000 GeV.Errors are statistical and systematic added in quadrature.

Measured differential yield of charged hadrons as a function oftransverse momentum for pseudorapidities 1.7, 1.9, 2.1 and 2.3 for centre-of-mass energy 7000 GeV.Errors are statistical and systematic added in quadrature.

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Transverse Momentum and Pseudorapidity Distributions of Charged Hadrons in pp Collisions at $\sqrt{s} = 0.9$ and 2.36 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M. ; Tumasyan, Armen ; et al.
JHEP 02 (2010) 041, 2010.
Inspire Record 845323 DOI 10.17182/hepdata.54829

Measurements of inclusive charged-hadron transverse-momentum and pseudorapidity distributions are presented for proton-proton collisions at sqrt(s) = 0.9 and 2.36 TeV. The data were collected with the CMS detector during the LHC commissioning in December 2009. For non-single-diffractive interactions, the average charged-hadron transverse momentum is measured to be 0.46 +/- 0.01 (stat.) +/- 0.01 (syst.) GeV/c at 0.9 TeV and 0.50 +/- 0.01 (stat.) +/- 0.01 (syst.) GeV/c at 2.36 TeV, for pseudorapidities between -2.4 and +2.4. At these energies, the measured pseudorapidity densities in the central region, dN(charged)/d(eta) for |eta| < 0.5, are 3.48 +/- 0.02 (stat.) +/- 0.13 (syst.) and 4.47 +/- 0.04 (stat.) +/- 0.16 (syst.), respectively. The results at 0.9 TeV are in agreement with previous measurements and confirm the expectation of near equal hadron production in p-pbar and pp collisions. The results at 2.36 TeV represent the highest-energy measurements at a particle collider to date.

8 data tables

Measured differential yield of charged hadrons as a function of transverse momentum for pseudorapidities 0.1, 0.3, 0.5 and 0.7 for centre-of-mass energy 900 GeV.

Measured differential yield of charged hadrons as a function of transverse momentum for pseudorapidities 0.9, 1.1, 1.3 and 1.5 for centre-of-mass energy 900 GeV.

Measured differential yield of charged hadrons as a function of transverse momentum for pseudorapidities 1.7, 1.9, 2.1 and 2.3 for centre-of-mass energy 900 GeV.

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First Measurement of the Underlying Event Activity at the LHC with $\sqrt{s} = 0.9$ TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M. ; Tumasyan, Armen ; et al.
Eur.Phys.J.C 70 (2010) 555-572, 2010.
Inspire Record 857644 DOI 10.17182/hepdata.55126

A measurement of the underlying activity in scattering processes with transverse momentum scale in the GeV region is performed in proton-proton collisions at sqrt(s) = 0.9 TeV, using data collected by the CMS experiment at the LHC. Charged hadron production is studied with reference to the direction of a leading object, either a charged particle or a set of charged particles forming a jet. Predictions of several QCD-inspired models as implemented in PYTHIA are compared, after full detector simulation, to the data. The models generally predict too little production of charged hadrons with pseudorapidity eta < 2, p_T > 0.5 GeV/c, and azimuthal direction transverse to that of the leading object.

7 data tables

Average multiplicity of charged particles per unit of pseudorapidity as a function of pseudorapidity for events with leading track-jet transverse momenta > 1 and > 3 GeV. Statistical errors only.

Average scalar sum of the transverse momenta of charged particles per unit of pseusdorapidity and per radian as a function of DELTA(PHI) for events with leading track-jet transverse momenta > 1 and > 2 GeV. Statistical errors only. Typical systematic error of 1.8 PCT at a leading track-jet PT of 3.5 GeV.

The average multiplicity and average scalar sum of transverse momenta of charge particles per unit of pseudorapidity and per radian as a function of the leading track transverse momenta. Statistical errors only. Typical systematic error of 1.8 PCT at a leading track-jet PT of 3.5 GeV.

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