Study of the inclusive production of charged pions, kaons, and protons in pp collisions at sqrt(s) = 0.9, 2.76, and 7 TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
Eur.Phys.J.C 72 (2012) 2164, 2012.
Inspire Record 1123117 DOI 10.17182/hepdata.59366

Spectra of identified charged hadrons are measured in pp collisions at the LHC for sqrt(s) = 0.9, 2.76, and 7 TeV. Charged pions, kaons, and protons in the transverse-momentum range pt approximately 0.1-1.7 GeV and for rapidities abs(y) < 1 are identified via their energy loss in the CMS silicon tracker. The average pt increases rapidly with the mass of the hadron and the event charged-particle multiplicity, independently of the center-of-mass energy. The fully corrected pt spectra and integrated yields are compared to various tunes of the PYTHIA6 and PYTHIA8 event generators.

80 data tables

Measured transverse momentum distributions of identified charged hadrons (PI+, K+ and P) and at a centre-of-mass energy of 900 GeV.

Measured transverse momentum distributions of identified charged hadrons (PI-, K- and PBAR) and at a centre-of-mass energy of 900 GeV.

Measured transverse momentum distributions of identified charged hadrons (PI+, K+ and P) and at a centre-of-mass energy of 2760 GeV.

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Measurements of the Upsilon(1S), Upsilon(2S), and Upsilon(3S) differential cross sections in pp collisions at sqrt(s) = 7 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Lett.B 749 (2015) 14-34, 2015.
Inspire Record 1342266 DOI 10.17182/hepdata.64486

Differential cross sections as a function of transverse momentum pt are presented for the production of Y(nS) (n = 1, 2, 3) states decaying into a pair of muons. Data corresponding to an integrated luminosity of 4.9 inverse femtobarns in pp collisions at sqrt(s) = 7 TeV were collected with the CMS detector at the LHC. The analysis selects events with dimuon rapidity abs(y) < 1.2 and dimuon transverse momentum in the range 10 < pt < 100 GeV. The measurements show a transition from an exponential to a power-law behavior at pt ~ 20 GeV for the three Y states. Above that transition, the Y spectrum is significantly harder than that of the Y(1S) and Y(2S). The ratios of the Y(3S) and Y(2S) differential cross sections to the Y(1S) cross section show a rise as pt increases at low pt, then become flatter at higher pt.

15 data tables

The $p_{\rm T}$ bin width, the weighted mean $p_{\rm T}$ within a bin, and the differential cross section times the dimuon branching fraction for the $\Upsilon$(1S), $\Upsilon$(2S), and $\Upsilon$(3S) with $0 < |y| < 0.6$. The statistical and systematic uncertainties in the differential cross section are given as the percentage of the cross section.

The $p_{\rm T}$ bin width, the weighted mean $p_{\rm T}$ within a bin, and the differential cross section times the dimuon branching fraction for the $\Upsilon$(1S), $\Upsilon$(2S), and $\Upsilon$(3S) with $0.6 < |y| < 1.2$. The statistical and systematic uncertainties in the differential cross section are given as the percentage of the cross section.

The $p_{\rm T}$ bin width, the weighted mean $p_{\rm T}$ within a bin, and the differential cross section times the dimuon branching fraction for the $\Upsilon$(1S), $\Upsilon$(2S), and $\Upsilon$(3S) with $|y| < 1.2$. The statistical and systematic uncertainties in the differential cross section are given as the percentage of the cross section.

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Search for Displaced Supersymmetry in events with an electron and a muon with large impact parameters

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Rev.Lett. 114 (2015) 061801, 2015.
Inspire Record 1317640 DOI 10.17182/hepdata.66763

A search for new long-lived particles decaying to leptons is presented using proton-proton collisions produced by the LHC at sqrt(s) = 8 TeV. Data used for the analysis were collected by the CMS detector and correspond to an integrated luminosity of 19.7 inverse femtobarns. Events are selected with an electron and a muon that have transverse impact parameter values between 0.02 cm and 2 cm. The search has been designed to be sensitive to a wide range of models with nonprompt e-mu final states. Limits are set on the "displaced supersymmetry" model, with pair production of top squarks decaying into an e-mu final state via R-parity-violating interactions. The results are the most restrictive to date on this model, with the most stringent limit being obtained for a top squark lifetime corresponding to c tau = 2 cm, excluding masses below 790 GeV at 95% confidence level.

8 data tables

Electron transverse impact parameter distribution for data and expected background processes after the preselection requirements have been applied. The event yields per bin have been rescaled to account for the varying bin sizes. The rightmost bin contains the overflow entries.

Muon transverse impact parameter distribution for data and expected background processes after the preselection requirements have been applied. The event yields per bin have been rescaled to account for the varying bin sizes. The rightmost contains the overflow entries.

Numbers of expected and observed events in the three search regions (see the text for the definitions of these regions). Background and signal expectations are quoted as $N_{\text{exp}} \pm 1\sigma$ stat $\pm 1\sigma$ syst. If the estimated background is zero in a particular search region, the estimate is instead taken from the preceding region. Since this should always overestimate the background, we denote this by a preceding "<".

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Measurement of four-jet production in proton-proton collisions at sqrt(s)=7 TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
Phys.Rev.D 89 (2014) 092010, 2014.
Inspire Record 1273574 DOI 10.17182/hepdata.66510

Measurements of the differential cross sections for the production of exactly four jets in proton-proton collisions are presented as a function of the transverse momentum pt and pseudorapidity eta, together with the correlations in azimuthal angle and the pt balance among the jets. The data sample was collected in 2010 at a center-of-mass energy of 7 TeV with the CMS detector at the LHC, with an integrated luminosity of 36 inverse picobarns. The cross section for a final state with a pair of hard jets with pt > 50 GeV and another pair with pt > 20 GeV within abs(eta) < 4.7 is measured to be sigma = 330 +- 5 (stat.) +- 45 (syst.) nb. It is found that fixed-order matrix element calculations including parton showers describe the measured differential cross sections in some regions of phase space only, and that adding contributions from double parton scattering brings the Monte Carlo predictions closer to the data.

12 data tables

The measured fiducial cross section. The first uncertainty is the statistical one, the second uncertainty is the combined systematic uncertainty including luminosity, jet energy scale, model dependence and jet energy resolution and trigger efficiency correction.

Differential cross section as a function of the transverse momentum PT of the leading jet. The first uncertainty is the statistical one, the second uncertainty is the combined systematic uncertainty including luminosity, jet energy scale, model dependence and jet energy resolution and trigger efficiency correction.

Differential cross section as a function of the transverse momentum PT of the subleading jet. The first uncertainty is the statistical one, the second uncertainty is the combined systematic uncertainty including luminosity, jet energy scale, model dependence and jet energy resolution and trigger efficiency correction.

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Measurements of jet multiplicity and differential production cross sections of Z+jets events in proton-proton collisions at sqrt(s)=7 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Rev.D 91 (2015) 052008, 2015.
Inspire Record 1310737 DOI 10.17182/hepdata.67635

Measurements of differential cross sections are presented for the production of a Z boson and at least one hadronic jet in proton-proton collisions at sqrt(s) = 7 TeV, recorded by the CMS detector, using a data sample corresponding to an integrated luminosity of 4.9 inverse femtobarns. The jet multiplicity distribution is measured for up to six jets. The differential cross sections are measured as a function of jet transverse momentum and pseudorapidity for the four highest transverse momentum jets. The distribution of the scalar sum of jet transverse momenta is also measured as a function of the jet multiplicity. The measurements are compared with theoretical predictions at leading and next-to-leading order in perturbative QCD.

14 data tables

The cross section measurement as a function of the exclusive jet multiplicity, for jet multiplicities of up to 6.

The cross section measurement as a function of the inclusive jet multiplicity, for jet multiplicities of up to 6.

The cross section measurement as a function of the transverse momentum of the leading jet.

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Differential cross section measurements for the production of a W boson in association with jets in proton-proton collisions at sqrt(s) = 7 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Lett.B 741 (2015) 12-37, 2015.
Inspire Record 1303894 DOI 10.17182/hepdata.67318

Measurements are reported of differential cross sections for the production of a W boson, which decays into a muon and a neutrino, in association with jets, as a function of several variables, including the transverse momenta (pt) and pseudorapidities of the four leading jets, the scalar sum of jet transverse momenta (HT), and the difference in azimuthal angle between the directions of each jet and the muon. The data sample of pp collisions at a centre-of-mass energy of 7 TeV was collected with the CMS detector at the LHC and corresponds to an integrated luminosity of 5.0 inverse femtobarns. The measured cross sections are compared to predictions from Monte Carlo generators, MADGRAPH + PYTHIA and SHERPA, and to next-to-leading-order calculations from BLACKHAT + SHERPA. The differential cross sections are found to be in agreement with the predictions, apart from the pt distributions of the leading jets at high pt values, the distributions of the HT at high-HT and low jet multiplicity, and the distribution of the difference in azimuthal angle between the leading jet and the muon at low values.

18 data tables

The cross section measurement as a function of the exclusive jet multiplicity, for jet multiplicities of up to 6.

The cross section measurement as a function of the inclusive jet multiplicity, for jet multiplicities of up to 6.

The differential cross section measurement as a function of the transverse momentum of the first leading jet.

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Jet and underlying event properties as a function of particle multiplicity in proton-proton collisions at sqrt(s) = 7 TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
Eur.Phys.J.C 73 (2013) 2674, 2013.
Inspire Record 1261026 DOI 10.17182/hepdata.68128

Characteristics of multi-particle production in proton-proton collisions at $\sqrt{s}$=7 TeV are studied as a function of the charged-particle multiplicity, $N_{ch}$. The produced particles are separated into two classes: those belonging to jets and those belonging to the underlying event. Charged particles are measured with pseudorapidity |η|<2.4 and transverse momentum $p_T$ > 0.25 GeV/c. Jets are reconstructed from charged-particles only and required to have $p_T$ > 5 GeV/c. The distributions of jet $p_T$, average $p_T$ of charged particles belonging to the underlying event or to jets, jet rates, and jet shapes are presented as functions of $N_{ch}$ and compared to the predictions of the PYTHIA and HERWIG event generators. Predictions without multi-parton interactions fail completely to describe the $N_{ch}$-dependence observed in the data. For increasing $N_{ch}$, PYTHIA systematically predicts higher jet rates and harder $p_T$ spectra than seen in the data, whereas HERWIG shows the opposite trends. At the highest multiplicity, the data–model agreement is worse for most observables, indicating the need for further tuning and/or new model ingredients.

17 data tables

Mean $p_T$, all charged particles.

Mean $p_T$, UE charged particles.

Mean $p_T$, in-jet charged particles.

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Measurement of the triple-differential cross section for photon+jets production in proton-proton collisions at sqrt(s)=7 TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
JHEP 06 (2014) 009, 2014.
Inspire Record 1266056 DOI 10.17182/hepdata.64869

A measurement of the triple-differential cross section (sigma as a function of the photon pt and eta and the jet eta) in photon + jets final states using a data sample from proton-proton collisions at sqrt(s) = 7 TeV is presented. This sample corresponds to an integrated luminosity of 2.14 inverse femtobarns collected by the CMS detector at the LHC. Photons and jets are reconstructed within a pseudorapidity range of abs(eta) < 2.5, and are required to have transverse momenta in the range 40 < pt(gamma) < 300 GeV and pt(jet) > 30 GeV, respectively. The measurements are compared to theoretical predictions from the SHERPA leading-order QCD Monte Carlo event generator and the next-to-leading-order perturbative QCD calculation from JETPHOX. The predictions are found to be consistent with the data over most of the examined kinematic region.

4 data tables

The triple-differential cross sections d3sig/(dp^gamma_T deta^gamma deta^jet) for photons located in the central region ,|eta(gamma)|<0.9. A 2.2 PCT luminosity uncertainty is included in the systematic uncertainty.

The triple-differential cross sections d3sig/(dp^gamma_T deta^gamma deta^jet) for photons located in the central region,|eta(gamma)|=0.9-1.44. A 2.2 PCT luminosity uncertainty is included in the systematic uncertainty.

The triple-differential cross sections d3sig/(dp_T^gamma deta^gamma deta^jet) for photons located in forward region,|eta(gamma)|=1.57-2.1. A 2.2% luminosity uncertainty is included in the systematic uncertainty.

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Measurement of the underlying event in the Drell-Yan process in proton-proton collisions at sqrt(s) = 7 TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
Eur.Phys.J.C 72 (2012) 2080, 2012.
Inspire Record 1107658 DOI 10.17182/hepdata.68072

A measurement of the underlying event (UE) activity in proton-proton collisions at a center-of-mass energy of 7 TeV is performed using Drell--Yan events in a data sample corresponding to an integrated luminosity of 2.2 inverse femtobarns, collected by the CMS experiment at the LHC. The activity measured in the muonic final state (q q-bar to opposite-sign muons) is corrected to the particle level and compared with the predictions of various Monte Carlo generators and hadronization models. The dependence of the UE activity on the dimuon invariant mass is well described by PYTHIA and HERWIG++ tunes derived from the leading jet/track approach, illustrating the universality of the UE activity. The UE activity is observed to be independent of the dimuon invariant mass in the region above 40 GeV, while a slow increase is observed with increasing transverse momentum of the dimuon system. The dependence of the UE activity on the transverse momentum of the dimuon system is accurately described by MADGRAPH, which simulates multiple hard emissions.

20 data tables

Toward $N_\text{chg}$ density vs $p_\perp^{\mu\mu}$.

Transverse $N_\text{chg}$ density vs $p_\perp^{\mu\mu}$.

Away $N_\text{chg}$ density vs $p_\perp^{\mu\mu}$.

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Measurement of the Z gamma production cross section in pp collisions at 8 TeV and search for anomalous triple gauge boson couplings

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
JHEP 04 (2015) 164, 2015.
Inspire Record 1345354 DOI 10.17182/hepdata.66985

The cross section for the production of Z gamma in proton-proton collisions at 8 TeV is measured based on data collected by the CMS experiment at the LHC corresponding to an integrated luminosity of 19.5 inverse femtobarns. Events with an oppositely-charged pair of muons or electrons together with an isolated photon are selected. The differential cross section as a function of the photon transverse momentum is measured inclusively and exclusively, where the exclusive selection applies a veto on central jets. The observed cross sections are compatible with the expectations of next-to-next-to-leading-order quantum chromodynamics. Limits on anomalous triple gauge couplings of Z Z gamma and Z gamma gamma are set that improve on previous experimental results obtained with the charged lepton decay modes of the Z boson.

4 data tables

Inclusive fiducial cross sections in bins of pT(gamma) with statistical, systematic, and luminosity uncertainties, respectivley. Results are not divided by bin-widths. The last bin is the cross section for pT(gamma) > 120 GeV. Combined result of electron and muon channels.

Fiducial cross sections with jet-veto in bins of pT(gamma) with statistical, systematic, and luminosity uncertainties, respectivley. Results are not divided by bin-widths. The last bin is the cross section for pT(gamma) > 120 GeV. Combined result of electron and muon channels.

Ratio of fiducial cross section with jet-veto and the inclusive cross section in bins of pT(gamma). The last bin is the cross section for pT(gamma) > 120 GeV. Combined result of electron and muon channels.

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