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. B700 (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.

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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.

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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 1105 (2011) 029, 2011.
Inspire Record 884808 DOI 10.17182/hepdata.60018
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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.

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Observation of s-channel production of single top quarks at the Tevatron

The CDF & D0 collaborations Aaltonen, Timo Antero ; Abazov, Victor Mukhamedovich ; Abbott, Braden Keim ; et al.
Phys.Rev.Lett. 112 (2014) 231803, 2014.
Inspire Record 1282028 DOI 10.17182/hepdata.64717

We report the first observation of single-top-quark production in the s channel through the combination of the CDF and D0 measurements of the cross section in proton-antiproton collisions at a center-of-mass energy of 1.96 TeV. The data correspond to total integrated luminosities of up to 9.7 fb-1 per experiment. The measured cross section is $\sigma_s = 1.29^{+0.26}_{-0.24}$ pb. The probability of observing a statistical fluctuation of the background to a cross section of the observed size or larger is $1.8 \times 10^{-10}$, corresponding to a significance of 6.3 standard deviations for the presence of an s-channel contribution to the production of single-top quarks.

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Measurement of the $B^0$ production cross section in $pp$ Collisions at $\sqrt{s}=7$ TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
Phys.Rev.Lett. 106 (2011) 252001, 2011.
Inspire Record 896211 DOI 10.17182/hepdata.57688

Measurements of the differential production cross sections in transverse momentum and rapidity for B0 mesons produced in pp collisions at sqrt(s) = 7 TeV are presented. The dataset used was collected by the CMS experiment at the LHC and corresponds to an integrated luminosity of 40 inverse picobarns. The production cross section is measured from B0 meson decays reconstructed in the exclusive final state J/Psi K-short, with the subsequent decays J/Psi to mu^+ mu^- and K-short to pi^+ pi^-. The total cross section for pt(B0) > 5 GeV and y(B0) < 2.2 is measured to be 33.2 +/- 2.5 +/- 3.5 microbarns, where the first uncertainty is statistical and the second is systematic.

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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. D83 (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.

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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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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. B699 (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.

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

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
JHEP 1110 (2011) 132, 2011.
Inspire Record 919737 DOI 10.17182/hepdata.57964

A measurement of inclusive W and Z production cross sections in pp collisions at sqrt(s)=7 TeV is presented. The electron and muon decay channels are analyzed in a data sample collected with the CMS detector at the LHC and corresponding to an integrated luminosity of 36 inverse picobarns. The measured inclusive cross sections are sigma(pp-> WX) B(W-> l nu) = 10.30 +/- 0.02 (stat.) +/- 0.10 (syst.) +/- 0.10 (th.) +/- 0.41 (lumi.) nb and sigma(pp -> ZX) B(Z-> l^+l^-) = 0.974 +/- 0.007 (stat.) +/- 0.007 (syst.) +/- 0.018 (th.) +/- 0.039 (lumi.) nb, limited to the dilepton invariant mass range 60 to 120 GeV. The luminosity-independent cross section ratios are [sigma(pp->WX) B(W-> l nu)]/[sigma(pp-> ZX) B(Z->l^+l^-)] = 10.54 +/- 0.07 (stat.) +/- 0.08 (syst.) +/- 0.16 (th.) and [sigma(pp->W^+X) B(W^+ -> l^+nu)] / [sigma(pp->W^- X) B(W^- -> l^- nu)] = 1.421 +/- 0.006 (stat.) +/- 0.014 (syst.) +/- 0.029 (th.). The measured values agree with next-to-next-to-leading order QCD cross section calculations based on recent parton distribution functions.

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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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Measurement of the Strange $B$ Meson Production Cross Section with J/Psi $\phi$ Decays in $pp$ Collisions at $\sqrt{s}=7$ TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
Phys.Rev. D84 (2011) 052008, 2011.
Inspire Record 914325 DOI 10.17182/hepdata.57944

The B^0_s differential production cross section is measured as functions of the transverse momentum and rapidity in pp collisions at sqrt(s) = 7 TeV, using the J/Psi phi decay, and compared with predictions based on perturbative QCD calculations at next-to-leading order. The data sample, collected by the CMS experiment at the LHC, corresponds to an integrated luminosity of 40 inverse picobarns. The B^0_s is reconstructed from the decays J/Psi to an oppositely charged muon pair and phi to K+ K-. The integrated B^0_s cross section times B^0_s to J/Psi phi branching fraction in the range 8 < pt(B) < 50 GeV/c and |y(b)| < 2.4 is measured to be 6.9 +/- 0.6 +/- 0.6 nb, where the first uncertainty is statistical and the second is systematic.

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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
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Measurement of the $t\bar{t}$ production cross section using events in the e$\mu$ final state in pp collisions at $\sqrt{s} =$ 13 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
No Journal Information, 2016.
Inspire Record 1497736 DOI 10.17182/hepdata.76735

The cross section of top quark-antiquark pair production in proton-proton collisions at $\sqrt{s}$ = 13 TeV is measured by the CMS experiment at the LHC, using data corresponding to an integrated luminosity of 2.2 inverse femtobarns. The measurement is performed by analyzing events in which the final state includes one electron, one muon, and two or more jets, at least one of which is identified as originating from hadronization of a b quark. The measured cross section is 792 +/- 8 (stat) +/- 37 (syst) +/- 21 (lumi) pb, in agreement with the expectation from the standard model.

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Version 2
Suppression of $\Upsilon(1S)$, $\Upsilon(2S)$ and $\Upsilon(3S)$ production in PbPb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Lett.B, 2016.
Inspire Record 1495866 DOI 10.17182/hepdata.77220

The production yields of Upsilon(1S), Upsilon(2S), and Upsilon(3S) quarkonium states are measured through their decays into muon pairs in the CMS detector, in PbPb and pp collisions at the centre-of-mass energy per nucleon pair of 2.76 TeV. The data correspond to integrated luminosities of 166 inverse microbarns and 5.4 inverse picobarns for PbPb and pp collisions, respectively. Differential production cross sections are reported as functions of Upsilon rapidity $y$ up to 2.4, and transverse momentum pt up to 20 GeV/c. A strong centrality-dependent suppression is observed in PbPb relative to pp collisions, by factors of up to ~2 and 8, for the Upsilon(1S) and Upsilon(2S) states, respectively. No significant dependence of this suppression is observed as a function of y or pt. The Upsilon(3S) state is not observed in PbPb collisions, which corresponds to a suppression for the centrality-integrated data by at least a factor of ~7 at a 95% confidence level. The observed suppression is in agreement with theoretical scenarios modeling the sequential melting of quarkonium states in a quark gluon plasma.

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Azimuthal anisotropy of charged particles with transverse momentum up to 100 GeV in PbPb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2017.
Inspire Record 1511868 DOI 10.17182/hepdata.77603

The Fourier coefficients v[2] and v[3] characterizing the anisotropy of the azimuthal distribution of charged particles produced in PbPb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV are measured with data collected by the CMS experiment. The measurements cover a broad transverse momentum range, pt= 1-100 GeV. The analysis focuses on pt > 10 GeV range, where anisotropic azimuthal distributions should reflect the path-length dependence of parton energy loss in the created medium. Results are presented in several bins of PbPb collision centrality, spanning the 60x% most central events. The v[2] coefficient is measured with the scalar product and the multiparticle cumulant methods, which have different sensitivities to the initial-state fluctuations. The values of both methods remain positive up to pt ~ 70 GeV, in all examined centrality classes. The v[3] coefficient, only measured with the scalar product method, tends to zero for pt >~ 20 GeV. Comparisons between theoretical calculations and data provide new constraints on the path-length dependence of parton energy loss in heavy ion collisions and highlight the importance of the initial-state fluctuations.

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Study of jet quenching with Z+jet correlations in PbPb and pp collisions at $\sqrt{s_{NN}}$ = 5.02 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2017.
Inspire Record 1512112 DOI 10.17182/hepdata.77604

The production of jets in association with Z bosons, reconstructed via the mu+mu- and e+e- decay channels, is studied in pp and, for the first time, in PbPb collisions. Both data samples were collected by the CMS experiment at the LHC, at a center-of-mass energy of 5.02 TeV. The PbPb collisions were analyzed in the 0-30% centrality range. The back-to-back azimuthal alignment was studied in both pp and PbPb collisions for Z bosons with transverse momentum ptz > 60 GeV/c and a recoiling jet with ptj > 30 GeV/c. The pt imbalance, xjz= ptj/ptz, as well as the average number of jet partners per Z, rjz, were studied in intervals of ptz, in both pp and PbPb collisions. The rjz is found to be smaller in PbPb than in pp collisions, which suggests that in PbPb collisions a larger fraction of partons, associated with the Z bosons, lose energy and fall below the 30 GeV/c ptj threshold.

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Relative modification of prompt $ {\psi\mathrm{(2S)}} $ and $\mathrm{J}/\psi $ yields from pp to PbPb collisions at ${\sqrt{s_{\mathrm{NN}}}} = $ 5.02 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Rev.Lett., 2016.
Inspire Record 1495840 DOI 10.17182/hepdata.77102

The relative modification of the prompt psi(2S) and J/psi yields from pp to PbPb collisions, at the center of mass energy of 5.02 TeV per nucleon pair, is presented. The analysis is based on pp and PbPb data samples collected by the CMS experiment at the LHC in 2015, corresponding to integrated luminosities of 28.0 inverse picobarns and 464 inverse microbarns, respectively. The double ratio of measured yields of prompt charmonia reconstructed through their decays into muon pairs, (N[psi(2S)]/N[J/psi])[PbPb]/ (N[psi(2S)]/N[J/psi])[pp], is determined as a function of PbPb collision centrality and charmonium transverse momentum pt, in two kinematic intervals: abs(y) < 1.6 covering 6.5 < pt < 30GeV/c and 1.6 < abs(y) < 2.4 covering 3 <pt< 30GeV/c. The centrality-integrated double ratios are 0.36 +/- 0.08 (stat) +/-0.05 (syst) in the first interval and 0.24 +/- 0.22 (stat) +/- 0.09 (syst) in the second. The double ratio is lower than unity in all the measured bins, suggesting that the psi(2S) yield is more suppressed than the J/psi yield in the explored phase space.

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Observation of charge-dependent azimuthal correlations in pPb collisions and its implication for the search for the chiral magnetic effect

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Rev.Lett, 2016.
Inspire Record 1489183 DOI 10.17182/hepdata.77013

Charge-dependent azimuthal particle correlations with respect to the second-order event plane in pPb and PbPb collisions at a nucleon-nucleon center-of-mass energy of 5.02 TeV have been studied with the CMS experiment at the LHC. The measurement is performed with a three-particle correlation technique, using two particles with the same or opposite charge within the pseudorapidity range abs(eta)<2.4, and a third particle measured in the hadron forward calorimeters (4.4< abs(eta)<5). The observed differences between the same and opposite sign correlations, as functions of multiplicity and eta gap between the two charged particles, are of similar magnitude in pPb and PbPb collisions at the same multiplicities. These results pose a challenge for the interpretation of charge-dependent azimuthal correlations in heavy ion collisions in terms of the chiral magnetic effect.

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Search for anomalous couplings in boosted $\mathrm{ WW/WZ }\to\ell\nu\mathrm{ q \bar{q} }$ production in proton-proton collisions at $\sqrt{s} =$ 8 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Lett. B772 (2017) 21-42, 2017.
Inspire Record 1518145 DOI 10.17182/hepdata.78151

This Letter presents a search for new physics manifested as anomalous triple gauge boson couplings in WW and WZ diboson production in proton–proton collisions. The search is performed using events containing a W boson that decays leptonically and a W or Z boson whose decay products are merged into a single reconstructed jet. The data, collected at s=8 TeV with the CMS detector at the LHC, correspond to an integrated luminosity of 19 fb−1 . No evidence for anomalous triple gauge couplings is found and the following 95% confidence level limits are set on their values: λ ( [−0.011,0.011] ), Δκγ ( [−0.044,0.063] ), and Δg1Z ( [−0.0087,0.024] ). These limits are also translated into their effective field theory equivalents: cWWW/Λ2 ( [−2.7,2.7] TeV−2 ), cB/Λ2 ( [−14,17] TeV−2 ), and cW/Λ2 ( [−2.0,5.7] TeV−2 ).

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Search for supersymmetry in events with at least one photon, missing transverse momentum, and large transverse event activity in proton-proton collisions at $ \sqrt{s}=13 $ TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
JHEP 1712 (2017) 142, 2017.
Inspire Record 1610629 DOI 10.17182/hepdata.79807

A search for physics beyond the standard model in final states with at least one photon, large transverse momentum imbalance, and large total transverse event activity is presented. Such topologies can be produced in gauge-mediated supersymmetry models in which pair-produced gluinos or squarks decay to photons and gravitinos via short-lived neutralinos. The data sample corresponds to an integrated luminosity of 35.9 inverse femtobarns of proton-proton collisions at sqrt(s) = 13 TeV recorded by the CMS experiment at the LHC in 2016. No significant excess of events above the expected standard model background is observed. The data are interpreted in simplified models of gluino and squark pair production, in which gluinos or squarks decay via neutralinos to photons. Gluino masses of up to 1.50-2.00 TeV and squark masses up to 1.30-1.65 TeV are excluded at 95% confidence level, depending on the neutralino mass and branching fraction.

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Search for Charged Higgs Bosons Produced via Vector Boson Fusion and Decaying into a Pair of $W$ and $Z$ Bosons Using $pp$ Collisions at $\sqrt{s}=13\text{ }\text{ }\mathrm{TeV}$

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Rev.Lett. 119 (2017) 141802, 2017.
Inspire Record 1598467 DOI 10.17182/hepdata.80233

A search for charged Higgs bosons produced via vector boson fusion and decaying into W and Z bosons using proton-proton collisions at s=13  TeV is presented. The data sample corresponds to an integrated luminosity of 15.2  fb-1 collected with the CMS detector in 2015 and 2016. The event selection requires three leptons (electrons or muons), two jets with large pseudorapidity separation and high dijet mass, and missing transverse momentum. The observation agrees with the standard model prediction. Limits on the vector boson fusion production cross section times branching fraction for new charged physical states are reported as a function of mass from 200 to 2000 GeV and interpreted in the context of Higgs triplet models.

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Suppression of excited Upsilon states relative to the ground state in PbPb collisions at sqrt(sNN) = 5.02 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2017.
Inspire Record 1605750 DOI 10.17182/hepdata.79055

The relative yields of Upsilon mesons produced in pp and PbPb collisions at sqrt(s[NN]) = 5.02 TeV and reconstructed via the dimuon decay channel are measured using data collected by the CMS experiment. Double ratios are formed by comparing the yields of the excited states, Upsilon(2S) and Upsilon(3S), to the ground state, Upsilon(1S), in both PbPb and pp collisions at the same center-of-mass energy. The double ratios, [Upsilon(nS)/Upsilon(1S)](PbPb)/[Upsilon(nS)/Upsilon(1S)](pp), are measured to be 0.308 +/- 0.055 (stat) +/- 0.019 (syst) for the Upsilon(2S) and less than 0.26 at 95% confidence level for the Upsilon(3S). No significant Upsilon(3S) signal is found in the PbPb data. The double ratios are studied as a function of collision centrality, as well as dimuon transverse momentum and rapidity. No significant dependencies are observed.

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Measurement of prompt D0 meson azimuthal anisotropy in PbPb collisions at sqrt(s[NN]) = 5.02 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2017.
Inspire Record 1615780 DOI 10.17182/hepdata.78930

The prompt D0 meson azimuthal anisotropy coefficients, v[2] and v[3], are measured at midrapidity (abs(y) < 1.0) in PbPb collisions at a center-of-mass energy sqrt(s[NN]) = 5.02 TeV per nucleon pair with data collected by the CMS experiment. The measurement is performed in the transverse momentum (pT) range of 1 to 40 GeV/c, for central and midcentral collisions. The v[2] coefficient is found to be positive throughout the pT range studied. The first measurement of the prompt D0 meson v[3] coefficient is performed, and values up to 0.07 are observed for pT around 4 GeV/c. Compared to measurements of charged particles, a similar pT dependence, but smaller magnitude for pT < 6 GeV/c, is found for prompt D0 meson v[2] and v[3] coefficients. The results are consistent with the presence of collective motion of charm quarks at low pT and a path length dependence of charm quark energy loss at high pT, thereby providing new constraints on the theoretical description of the interactions between charm quarks and the quark-gluon plasma.

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Constraints on the chiral magnetic effect using charge-dependent azimuthal correlations in pPb and PbPb collisions at the LHC

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2017.
Inspire Record 1614482 DOI 10.17182/hepdata.82637

Charge-dependent azimuthal correlations of same- and opposite-sign pairs with respect to the second- and third-order event planes have been measured in pPb collisions at sqrt(s[NN]) = 8.16 TeV and PbPb collisions at 5.02TeV with the CMS experiment at the LHC. The measurement is motivated by the search for the charge separation phenomenon predicted by the chiral magnetic effect (CME) in heavy ion collisions. Three- and two-particle azimuthal correlators are extracted as functions of the pseudorapidity difference, the transverse momentum (pt) difference, and the pt average of same- and opposite-charge pairs in various event multiplicity ranges. The data suggest that the charge-dependent three-particle correlators with respect to the second- and third-order event planes share a common origin, predominantly arising from charge-dependent two-particle azimuthal correlations coupled with an anisotropic flow. The CME is expected to lead to a v[2]-independent three-particle correlation when the magnetic field is fixed. Using an event shape engineering technique, upper limits on the v[2]-independent fraction of the three-particle correlator are estimated to be 6.6% for pPb and 3.8% for PbPb collisions at 95% confidence level. The results of this analysis, both the dominance of two-particle correlations as a source of the three-particle results and the similarities seen between PbPb and pPb, provide stringent constraints on the origin of charge-dependent three-particle azimuthal correlations and challenge their interpretation as arising from a chiral magnetic effect in heavy ion collisions.

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