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Dependence on pseudorapidity and centrality of charged hadron production in PbPb collisions at a nucleon-nucleon centre-of-mass energy of 2.76 TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
JHEP 1108 (2011) 141, 2011.
Inspire Record 919733 DOI 10.17182/hepdata.58223

A measurement is presented of the charged hadron multiplicity in hadronic PbPb collisions, as a function of pseudorapidity and centrality, at a collision energy of 2.76 TeV per nucleon pair. The data sample is collected using the CMS detector and a minimum-bias trigger, with the CMS solenoid off. The number of charged hadrons is measured both by counting the number of reconstructed particle hits and by forming hit doublets of pairs of layers in the pixel detector. The two methods give consistent results. The charged hadron multiplicity density dN(ch)/d eta, evaluated at eta=0 for head-on collisions, is found to be 1612 +/- 55, where the uncertainty is dominated by systematic effects. Comparisons of these results to previous measurements and to various models are also presented.

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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.

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Properties of jets in Z boson events from 1.8 TeV $\bar{p}p$ collisions

The CDF collaboration Abe, F. ; Akimoto, H. ; Akopian, A. ; et al.
Phys.Rev.Lett. 77 (1996) 448-453, 1996.
Inspire Record 416570 DOI 10.17182/hepdata.42318

We present a study of events with Z bosons and hadronic jets produced in $\overline{p}p$ collisions at a center-of-mass energy of 1.8 TeV. The data consist of 6708 $Z \rightarrow e~+e~-$ decays from 106 pb$~{-1}$ of integrated luminosity collected using the CDF detector at the Tevatron Collider. The Z $+ \ge n$ jet cross sections and jet production properties have been measured for n = 1 to 4. The data compare well to predictions of leading order QCD matrix element calculations with added gluon radiation and simulated parton fragmentation.

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Properties of jets in $W$ boson events from 1.8 TeV $\bar{p}p$ collisions

The CDF collaboration Abe, F. ; Akimoto, H. ; Akopian, A. ; et al.
Phys.Rev.Lett. 79 (1997) 4760-4765, 1997.
Inspire Record 448076 DOI 10.17182/hepdata.54006

We present a study of events with W bosons and hadronic jets produced in pbar p collisions at a center of mass energy of 1.8 TeV. The data consist of 51400 W^+/- -> e^+/- nu decay candidates from 108 pb^-1 of integrated luminosity collected with the CDF detector at the Tevatron Collider. The cross sections and jet production properties have been measured for W + \geq 1 to \geq 4 jet events. The data are compared to predictions of leading order QCD matrix element calculations with added gluon radiation and simulated fragmentation.

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Study of the production of charged pions, kaons, and protons in pPb collisions at $\sqrt{s_{NN}} =\ $ 5.02 $\,\text {TeV}$

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
Eur.Phys.J. C74 (2014) 2847, 2014.
Inspire Record 1242440 DOI 10.17182/hepdata.63972

Spectra of identified charged hadrons are measured in pPb collisions with the CMS detector at the LHC at sqrt(sNN) = 5.02 TeV. Charged pions, kaons, and protons in the transverse-momentum range pt approximately 0.1-1.7 GeV and laboratory rapidity abs(y) < 1 are identified via their energy loss in the silicon tracker. The average pt increases with particle mass and the charged multiplicity of the event. The increase of the average pt with charged multiplicity is greater for heavier hadrons. Comparisons to Monte Carlo event generators reveal that EPOS LHC, which incorporates additional hydrodynamic evolution of the created system, is able to reproduce most of the data features, unlike HIJING and AMPT. The pt spectra and integrated yields are also compared to those measured in pp and PbPb collisions at various energies. The average transverse momentum and particle ratio measurements indicate that particle production at LHC energies is strongly correlated with event particle multiplicity.

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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

<p>A search for new long-lived particles decaying to leptons is presented using proton-proton collisions produced by the LHC at <inline-formula><mml:math display="inline"><mml:mrow><mml:msqrt><mml:mrow><mml:mi>s</mml:mi></mml:mrow></mml:msqrt><mml:mo>=</mml:mo><mml:mn>8</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:mi>TeV</mml:mi></mml:mrow></mml:math></inline-formula>. Data used for the analysis were collected by the CMS detector and correspond to an integrated luminosity of <inline-formula><mml:math display="inline"><mml:mrow><mml:mn>19.7</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:mrow><mml:msup><mml:mrow><mml:mi>fb</mml:mi></mml:mrow><mml:mrow><mml:mo>-</mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:msup></mml:mrow></mml:mrow></mml:math></inline-formula>. Events are selected with an electron and muon with opposite charges that both have transverse impact parameter values between 0.02 and 2 cm. The search has been designed to be sensitive to a wide range of models with nonprompt <inline-formula><mml:math display="inline"><mml:mrow><mml:mi>e</mml:mi><mml:mtext>-</mml:mtext><mml:mi>μ</mml:mi></mml:mrow></mml:math></inline-formula> final states. Limits are set on the “displaced supersymmetry” model, with pair production of top squarks decaying into an <inline-formula><mml:math display="inline"><mml:mrow><mml:mi>e</mml:mi><mml:mtext>-</mml:mtext><mml:mi>μ</mml:mi></mml:mrow></mml:math></inline-formula> final state via <inline-formula><mml:math display="inline"><mml:mi>R</mml:mi></mml:math></inline-formula>-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 <inline-formula><mml:math display="inline"><mml:mrow><mml:mi>c</mml:mi><mml:mi>τ</mml:mi><mml:mo>=</mml:mo><mml:mn>2</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:mi>cm</mml:mi></mml:mrow></mml:math></inline-formula>, excluding masses below 790 GeV at 95% confidence level.</p>

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Search for Monotop Signatures in Proton-Proton Collisions at $\sqrt s =$ 8 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Rev.Lett. 114 (2015) 101801, 2015.
Inspire Record 1320560 DOI 10.17182/hepdata.66092
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Evidence of b-Jet Quenching 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. 113 (2014) 132301, 2014.
Inspire Record 1269454 DOI 10.17182/hepdata.68931

The production of jets associated to bottom quarks is measured for the first time in PbPb collisions at a center-of-mass energy of 2.76 TeV per nucleon pair. Jet spectra are reported in the transverse momentum (pt) range of 80-250 GeV, and within pseudorapidity abs(eta < 2). The nuclear modification factor (R[AA]) calculated from these spectra shows a strong suppression in the b-jet yield in PbPb collisions relative to the yield observed in pp collisions at the same energy. The suppression persists to the largest values of pt studied, and is centrality dependent. The R[AA] is about 0.4 in the most central events, similar to previous observations for inclusive jets. This implies that jet quenching does not have a strong dependence on parton mass and flavor in the jet pt range studied.

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Measurement of isolated photon production in $pp$ and PbPb collisions at $\sqrt{s_{NN}}=2.76$ TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
Phys.Lett. B710 (2012) 256-277, 2012.
Inspire Record 1084729 DOI 10.17182/hepdata.58979

Isolated photon production is measured in proton-proton and lead-lead collisions at nucleon-nucleon centre-of-mass energies of 2.76 TeV in the pseudorapidity range |eta|<1.44 and transverse energies ET between 20 and 80 GeV with the CMS detector at the LHC. The measured ET spectra are found to be in good agreement with next-to-leading-order perturbative QCD predictions. The ratio of PbPb to pp isolated photon ET-differential yields, scaled by the number of incoherent nucleon-nucleon collisions, is consistent with unity for all PbPb reaction centralities.

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$K_s^0$ production in $\bar{p}p$ interactions at $\sqrt{s}=$ 630 GeV and 1800 GeV

The CDF collaboration Abe, F. ; Amidei, D. ; Apollinari, G. ; et al.
Phys.Rev. D40 (1989) 3791-3794, 1989.
Inspire Record 287811 DOI 10.17182/hepdata.22999
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Azimuthal Energy Flow in Deep Inelastic Neutrino Scattering

Mukherjee, A. ; Bofill, J. ; Busza, W. ; et al.
Phys.Rev.Lett. 60 (1988) 991, 1988.
Inspire Record 252080 DOI 10.17182/hepdata.3134
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Inclusive charged pion production in hadron nucleus interactions at 100-GeV/c and 320-GeV/c

Whitmore, J.J. ; Persi, F. ; Toothacker, W.S. ; et al.
Z.Phys. C62 (1994) 199-227, 1994.
Inspire Record 378192 DOI 10.17182/hepdata.14207
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POLARIZATION PARAMETERS AND ANGULAR DISTRIBUTIONS IN PI+- P ELASTIC SCATTERING AT 100-GEV/C AND IN P P ELASTIC SCATTERING AT 100-GEV/C AND 300-GEV/C

Kline, R.V. ; Law, M.E. ; Pipkin, F.M. ; et al.
Phys.Rev. D22 (1980) 553-572, 1980.
Inspire Record 158989 DOI 10.17182/hepdata.24156
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Diffractive Production of K0(s) K0(s) pi+ pi- pi- in pi- n Interactions at 200-GeV/c

Chang, C.C. ; Davis, T.C. ; Diamond, R.N. ; et al.
Phys.Rev. D29 (1984) 1888-1894, 1984.
Inspire Record 194648 DOI 10.17182/hepdata.23730
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Measurement of $WZ$ production in proton-proton collisions at $\sqrt{s}=7$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abajyan, Tatevik ; Abbott, Brad ; et al.
Eur.Phys.J. C72 (2012) 2173, 2012.
Inspire Record 1126131 DOI 10.17182/hepdata.59721

A study of WZ production in proton-proton collisions at sqrt(s) = 7 TeV is presented using data corresponding to an integrated luminosity of 4.6 fb^-1 collected with the ATLAS detector at the Large Hadron Collider in 2011. In total, 317 candidates, with a background expectation of 68+/-10 events, are observed in double-leptonic decay final states with electrons, muons and missing transverse momentum. The total cross-section is determined to be sigma_WZ(tot) = 19.0+1.4/-1.3(stat.)+/-0.9(syst.)+/-0.4(lumi.) pb, consistent with the Standard Model expectation of 17.6+1.1/-1.0 pb. Limits on anomalous triple gauge boson couplings are derived using the transverse momentum spectrum of Z bosons in the selected events. The cross section is also presented as a function of Z boson transverse momentum and diboson invariant mass.

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Measurement of $Z$ boson Production in Pb+Pb Collisions at $\sqrt{s_{NN}}=2.76$ TeV with the ATLAS Detector

The ATLAS collaboration Aad, Georges ; Abajyan, Tatevik ; Abbott, Brad ; et al.
Phys.Rev.Lett. 110 (2013) 022301, 2013.
Inspire Record 1193044 DOI 10.17182/hepdata.60336
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INCLUSIVE CHARGED CURRENT ANTI-NEUTRINO - NUCLEON INTERACTIONS AT HIGH-ENERGIES

The Fermilab-Serpukhov-Moscow-Michigan collaboration Ammosov, V.V. ; Denisov, A.G. ; Gapienko, G.S. ; et al.
Nucl.Phys. B199 (1982) 399-423, 1982.
Inspire Record 167339 DOI 10.17182/hepdata.41220
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Quark Jets from anti-neutrino Interactions. 2. Inclusive Particle Spectra and Multiplicities in the Quark Jets

Ammosov, V.V. ; Denisov, A.G. ; Gapienko, G.S. ; et al.
Nucl.Phys. B203 (1982) 1-15, 1982.
Inspire Record 156746 DOI 10.17182/hepdata.41254
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$W$ boson + jet angular distribution in $p\bar{p}$ collisions at $\sqrt{s} = 1.8$ TeV

The CDF collaboration Abe, F. ; Albrow, M.G. ; Amidei, D. ; et al.
Phys.Rev.Lett. 73 (1994) 2296-2300, 1994.
Inspire Record 374152 DOI 10.17182/hepdata.42492
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Jet pseudorapidity distribution in direct photon events in $p\bar{p}$ collisions at $\sqrt{s} = 1.8$ TeV

The CDF collaboration Abe, F. ; Albrow, M.G. ; Amendolia, S.R. ; et al.
Phys.Rev. D57 (1998) 1359-1365, 1998.
Inspire Record 453369 DOI 10.17182/hepdata.54263
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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. C72 (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.

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Search for top-quark partners with charge 5/3 in the same-sign dilepton final state

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
Phys.Rev.Lett. 112 (2014) 171801, 2014.
Inspire Record 1268328 DOI 10.17182/hepdata.65664

A search for the production of heavy partners of the top quark with charge 5/3 is performed in events with a pair of same-sign leptons. The data sample corresponds to an integrated luminosity of 19.5 inverse femtobarns and was collected at sqrt(s) = 8 TeV by the CMS experiment. No significant excess is observed in the data above the expected background and the existence of top-quark partners with masses below 800 GeV is excluded at a 95% confidence level, assuming they decay exclusively to tW. This is the first limit on these particles from the LHC, and it is significantly more restrictive than previous limits.

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Searches for new physics using the $t\bar{t}$ invariant mass distribution in pp collisions at $\sqrt{s}$=8  TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
Phys.Rev.Lett. 111 (2013) 211804, 2013.
Inspire Record 1253367 DOI 10.17182/hepdata.62178

Searches for anomalous top quark-antiquark production are presented, based on pp collisions at sqrt(s) = 8 TeV. The data, corresponding to an integrated luminosity of 19.7 inverse femtobarns, were collected with the CMS detector at the LHC. The observed ttbar invariant mass spectrum is found to be compatible with the standard model prediction. Limits on the production cross section times branching fraction probe, for the first time, a region of parameter space for certain models of new physics not yet constrained by precision measurements.

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Search for pair production of excited top quarks in the lepton + jets final state

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
JHEP 1406 (2014) 125, 2014.
Inspire Record 1265512 DOI 10.17182/hepdata.66136

A search is performed for pair-produced spin-3/2 excited top quarks t ∗ t ¯ ∗ , each decaying to a top quark and a gluon. The search uses data collected with the CMS detector from pp collisions at a center-of-mass energy of s = 8 TeV, selecting events that have a single isolated muon or electron, an imbalance in transverse momentum, and at least six jets, of which one must be compatible with originating from the fragmentation of a b quark. The data, corresponding to an integrated luminosity of 19.5 fb(−1), show no significant excess over standard model predictions, and provide a lower limit of 803 GeV at 95% confidence on the mass of the spin-3/2 t(*) quark in an extension of the Randall-Sundrum model, assuming a 100% branching fraction of its decay into a top quark and a gluon. This is the first search for a spin-3/2 excited top quark performed at the LHC.

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Study of Z production in PbPb and pp collisions at $ \sqrt{s_{\mathrm{NN}}}=2.76 $ TeV in the dimuon and dielectron decay channels

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
JHEP 1503 (2015) 022, 2015.
Inspire Record 1322726 DOI 10.17182/hepdata.66612
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