Measurement of the $\boldsymbol{W}$ boson production charge asymmetry in $\boldsymbol{p\bar{p}\rightarrow W+X \rightarrow e\nu +X}$ events at $\boldsymbol{\sqrt{s}=1.96}$ TeV

The D0 collaboration Abazov, Victor Mukhamedovich ; Abbott, Braden Keim ; Acharya, Bannanje Sripath ; et al.
Phys.Rev.Lett. 112 (2014) 151803, 2014.
Inspire Record 1268647 DOI 10.17182/hepdata.66256

We present a measurement of the $W$ boson production charge asymmetry in $p\bar{p}\rightarrow W+X \rightarrow e\nu +X$ events at a center of mass energy of 1.96 TeV, using 9.7 fb$^{-1}$ of integrated luminosity collected with the D0 detector at the Fermilab Tevatron Collider. The neutrino longitudinal momentum is determined using a neutrino weighting method, and the asymmetry is measured as a function of the $W$ boson rapidity. The measurement extends over wider electron pseudorapidity region than previous results, and is the most precise to date, allowing for precise determination of proton parton distribution functions in global fits.

2 data tables

${\it CP}$-folded $W$ charge asymmetry for data and predictions from MC@NLO using NNPDF2.3 PDFs tabulated in percent (%) for each $|y_W|$ bin. The $\langle|y_W|\rangle$ is calculated as the cross section weighted average of $y_W$ in each bin from RESBOS with photos. For data, the first uncertainty is statistical and the second is systematic. The uncertainties on the prediction come from both the PDF uncertainties and $\alpha_s$ uncertainties. The numbers in this table are the revised data published on 10th December 2014 (after the journal publication).

Correlation coefficients between central values of asymmetry in different $|y_W|$ bins.


Measurement of the combined rapidity and $p_T$ dependence of dijet azimuthal decorrelations in $p\bar{p}$ collisions at $\sqrt{s}=1.96\,$TeV

The D0 collaboration Abazov, Victor Mukhamedovich ; Abbott, Braden Keim ; Acharya, Bannanje Sripath ; et al.
Phys.Lett.B 721 (2013) 212-219, 2013.
Inspire Record 1206604 DOI 10.17182/hepdata.66543

We present the first combined measurement of the rapidity and transverse momentum dependence of dijet azimuthal decorrelations, based on the recently proposed quantity $R_{\Delta \phi}$. The variable $R_{\Delta \phi}$ measures the fraction of the inclusive dijet events in which the azimuthal separation of the two jets with the highest transverse momenta is less than a specified value for the parameter $\Delta \phi_{\rm max}$. The quantity $R_{\Delta \phi}$ is measured in $p\bar{p}$ collisions at $\sqrt{s}=1.96\,$TeV, as a function of the dijet rapidity interval, the total scalar transverse momentum, and $\Delta \phi_{\rm max}$. The measurement uses an event sample corresponding to an integrated luminosity of $0.7\,$fb$^{-1}$ collected with the D0 detector at the Fermilab Tevatron Collider. The results are compared to predictions of a perturbative QCD calculation at next-to-leading order in the strong coupling with corrections for non-perturbative effects. The theory predictions describe the data, except in the kinematic region of large dijet rapidity intervals and large $\Delta \phi_{\rm max}$.

3 data tables

The results for $R_{\Delta\phi}$ with their relative uncertainties for $\Delta\phi_{\rm max}=7\pi/8$.

The results for $R_{\delta\phi}$ with their relative uncertainties for $\delta\phi_{\rm max}=5\pi/6$.

The results for $R_{\delta\phi}$ with their relative uncertainties for $\delta\phi_{\rm max}=3\pi/4$.


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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Long-range two-particle correlations of strange hadrons with charged particles in pPb and PbPb collisions at LHC energies

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Lett.B 742 (2015) 200-224, 2015.
Inspire Record 1315947 DOI 10.17182/hepdata.66784

Measurements of two-particle angular correlations between an identified strange hadron (K0S or Lambda/anti-Lambda) and a charged particle, emitted in pPb collisions, are presented over a wide range in pseudorapidity and full azimuth. The data, corresponding to an integrated luminosity of approximately 35 inverse nanobarns, were collected at a nucleon-nucleon center-of-mass energy (sqrt(s[NN])) of 5.02 TeV with the CMS detector at the LHC. The results are compared to semi-peripheral PbPb collision data at sqrt(s[NN]) = 2.76 TeV, covering similar charged-particle multiplicities in the events. The observed azimuthal correlations at large relative pseudorapidity are used to extract the second-order (v[2]) and third-order (v[3]) anisotropy harmonics of K0S and Lambda/anti-Lambda particles. These quantities are studied as a function of the charged-particle multiplicity in the event and the transverse momentum of the particles. For high-multiplicity pPb events, a clear particle species dependence of v[2] and v[3] is observed. For pt < 2 GeV, the v[2] and v[3] values of K0S particles are larger than those of Lambda/anti-Lambda particles at the same pt. This splitting effect between two particle species is found to be stronger in pPb than in PbPb collisions in the same multiplicity range. When divided by the number of constituent quarks and compared at the same transverse kinetic energy per quark, both v[2] and v[3] for K0S particles are observed to be consistent with those for Lambda/anti-Lambda particles at the 10% level in pPb collisions. This consistency extends over a wide range of particle transverse kinetic energy and event multiplicities.

68 data tables

The elliptic flow v2(2, $|\Delta\eta| > 2$) extracted for all charged particles as a function of $p_{T}$ from the correlation in the $N_{offline}^{trk}$ < 35 multiplicity class in pPb.

The elliptic flow v2(2, $|\Delta\eta| > 2$) extracted for all charged particles as a function of $p_{T}$ from the correlation in the 35 $\leq N_{offline}^{trk}$ < 60 multiplicity class in pPb.

The elliptic flow v2(2, $|\Delta\eta| > 2$) extracted for all charged particles as a function of $p_{T}$ from the correlation in the 60 $\leq N_{offline}^{trk}$ < 120 multiplicity class in pPb.

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Evidence for collective multi-particle correlations in pPb collisions

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Rev.Lett. 115 (2015) 012301, 2015.
Inspire Record 1345262 DOI 10.17182/hepdata.67530

The second-order azimuthal anisotropy Fourier harmonics, v2, are obtained in pPb and PbPb collisions over a wide pseudorapidity (eta) range based on correlations among six or more charged particles. The pPb data, corresponding to an integrated luminosity of 35 inverse nanobarns, were collected during the 2013 LHC pPb run at a nucleon-nucleon center-of-mass energy of 5.02 TeV by the CMS experiment. A sample of semi-peripheral PbPb collision data at sqrt(s[NN])= 2.76 TeV, corresponding to an integrated luminosity of 2.5 inverse microbarns and covering a similar range of particle multiplicities as the pPb data, is also analyzed for comparison. The six- and eight-particle cumulant and the Lee-Yang zeros methods are used to extract the v2 coefficients, extending previous studies of two- and four-particle correlations. For both the pPb and PbPb systems, the v2 values obtained with correlations among more than four particles are consistent with previously published four-particle results. These data support the interpretation of a collective origin for the previously observed long-range (large Delta[eta]) correlations in both systems. The ratios of v2 values corresponding to correlations including different numbers of particles are compared to theoretical predictions that assume a hydrodynamic behavior of a pPb system dominated by fluctuations in the positions of participant nucleons. These results provide new insights into the multi-particle dynamics of collision systems with a very small overlapping region.

14 data tables

The cumulant $c_2\{6\}$ extracted for all charged particles with $0.3 < p_T < 3.0$ GeV/c as a function of $N_{trk}^{offline}$ in PbPb collisions.

The cumulant $c_2\{8\}$ extracted for all charged particles with $0.3 < p_T < 3.0$ GeV/c as a function of $N_{trk}^{offline}$ in PbPb collisions.

The cumulant $c_2\{6\}$ extracted for all charged particles with $0.3 < p_T < 3.0$ GeV/c as a function of $N_{trk}^{offline}$ in pPb collisions.

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Test of lepton flavor universality in B$^{\pm}$$\to$ K$^{\pm}\mu^+\mu^-$ and B$^{\pm}$$\to$ K$^{\pm}$e$^+$e$^-$ decays in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration Hayrapetyan, Aram ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
CMS-BPH-22-005, 2024.
Inspire Record 2747130 DOI 10.17182/hepdata.146018

A test of lepton flavor universality in B$^{\pm}$$\to$ K$^{\pm}\mu^+\mu^-$ and B$^{\pm}$$\to$ K$^{\pm}$e$^+$e$^-$ decays, as well as a measurement of differential and integrated branching fractions of a nonresonant B$^{\pm}$$\to$ K$^{\pm}\mu^+\mu^-$ decay are presented. The analysis is made possible by a dedicated data set of proton-proton collisions at $\sqrt{s}$ = 13 TeV recorded in 2018, by the CMS experiment at the LHC, using a special high-rate data stream designed for collecting about 10 billion unbiased b hadron decays. The ratio of the branching fractions $\mathcal{B}$(B$^{\pm}$$\to$ K$^{\pm}\mu^+\mu^-$) to $\mathcal{B}$(B$^{\pm}$$\to$ K$^{\pm}$e$^+$e$^-$) is determined from the measured double ratio $R$(K) of these decays to the respective branching fractions of the B$^\pm$$\to$ J/$\psi$K$^\pm$ with J/$\psi$$\to$$\mu^+\mu^-$ and e$^+$e$^-$ decays, which allow for significant cancellation of systematic uncertainties. The ratio $R$(K) is measured in the range 1.1 $\lt q^2 \lt$ 6.0 GeV$^2$, where $q$ is the invariant mass of the lepton pair, and is found to be $R$(K) = 0.78$^{+0.47}_{-0.23}$, in agreement with the standard model expectation $R$(K) $\approx$ 1. This measurement is limited by the statistical precision of the electron channel. The integrated branching fraction in the same $q^2$ range, $\mathcal{B}$(B$^{\pm}$$\to$ K$^{\pm}\mu^+\mu^-$) = (12.42 $\pm$ 0.68) $\times$ 10$^{-8}$, is consistent with the present world-average value and has a comparable precision.

9 data tables

The differential $\text{B}^+ \to \text{K}^+\mu^+\mu^-$ branching fraction measured in the individual $q^2$ bins. The uncertainties in the yields are statistical uncertainties from the fit, while the branching fraction uncertainties include both the statistical and systematic components.

Differential branching fraction $d\mathcal{B}/dq^2$, with theoretical predictions obtained with the HEPFiT, SuperIso, Flavio, and EOS packages. The HEPFiT predictions are available only for $q^2 < 8\ \mathrm{GeV}^2$.

Relative uncertainties in the differential branching fraction measurement of $\mathrm{B}^+\to\mathrm{K}^+\mu^+\mu^-$ per $q^2$ bin.

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Elliptic anisotropy measurement of the f$_0$(980) hadron in proton-lead collisions and evidence for its quark-antiquark composition

The CMS collaboration Hayrapetyan, Aram ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
CMS-HIN-20-002, 2023.
Inspire Record 2741119 DOI 10.17182/hepdata.146017

Despite the f$_0$(980) hadron having been discovered half a century ago, the question about its quark content has not been settled: it might be an ordinary quark-antiquark ($\mathrm{q\bar{q}}$) meson, a tetraquark ($\mathrm{q\bar{q}q\bar{q}}$) exotic state, a kaon-antikaon ($\mathrm{K\bar{K}}$) molecule, or a quark-antiquark-gluon ($\mathrm{q\bar{q}g}$) hybrid. This paper reports strong evidence that the f$_0$(980) state is an ordinary $\mathrm{q\bar{q}}$ meson, inferred from the scaling of elliptic anisotropies ($v_2$) with the number of constituent quarks ($n_\mathrm{q}$), as empirically established using conventional hadrons in relativistic heavy ion collisions. The f$_0$(980) state is reconstructed via its dominant decay channel f$_0$(980) $\to$$\pi^+\pi^-$, in proton-lead collisions recorded by the CMS experiment at the LHC, and its $v_2$ is measured as a function of transverse momentum ($p_\mathrm{T}$). It is found that the $n_q$ = 2 ($\mathrm{q\bar{q}}$ state) hypothesis is favored over $n_q$ = 4 ($\mathrm{q\bar{q}q\bar{q}}$ or $\mathrm{K\bar{K}}$ states) by 7.7, 6.3, or 3.1 standard deviations in the $p_\mathrm{T}$$\lt$ 10, 8, or 6 GeV/$c$ ranges, respectively, and over $n_\mathrm{q}$ = 3 ($\mathrm{q\bar{q}g}$ hybrid state) by 3.5 standard deviations in the $p_\mathrm{T}$$\lt$ 8 GeV/$c$ range. This result represents the first determination of the quark content of the f$_0$(980) state, made possible by using a novel approach, and paves the way for similar studies of other exotic hadron candidates.

6 data tables

The elliptic flow, $v_{2}$, for $f_0(980)$ as a function of $p_{T}$ in pPb collision at 8.16 TeV.

The elliptic flow after nonflow subtraction, $v_{2}^{sub}$, for $f_0(980)$ as a function of $p_{T}$ in pPb collision at 8.16 TeV.

The elliptic flow after nonflow subtraction, $v_{2}^{sub}/2$, for $f_0(980)$ as a function of $<KE_{T}>/2$ in pPb collision at 8.16 TeV.

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Evidence for transverse momentum and pseudorapidity dependent event plane fluctuations in PbPb and pPb collisions

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Rev.C 92 (2015) 034911, 2015.
Inspire Record 1347386 DOI 10.17182/hepdata.67151

A systematic study of the factorization of long-range azimuthal two-particle correlations into a product of single-particle anisotropies is presented as a function of pt and eta of both particles, and as a function of the particle multiplicity in PbPb and pPb collisions. The data were taken with the CMS detector for PbPb collisions at sqrt(s[NN]) = 2.76 TeV and pPb collisions at sqrt(s[NN]) = 5.02 TeV, covering a very wide range of multiplicity. Factorization is observed to be broken as a function of both particle pt and eta. When measured with particles of different pt, the magnitude of the factorization breakdown for the second Fourier harmonic reaches 20% for very central PbPb collisions but decreases rapidly as the multiplicity decreases. The data are consistent with viscous hydrodynamic predictions, which suggest that the effect of factorization breaking is mainly sensitive to the initial-state conditions rather than to the transport properties (e.g., shear viscosity) of the medium. The factorization breakdown is also computed with particles of different eta. The effect is found to be weakest for mid-central PbPb events but becomes larger for more central or peripheral PbPb collisions, and also for very high-multiplicity pPb collisions. The eta-dependent factorization data provide new insights to the longitudinal evolution of the medium formed in heavy ion collisions.

162 data tables

The $p_{T}$-dependent factorization ratio, $r_{2}$, as a function of $p^{a}_{T} - p^{b}_{T}$ for $1.0<p^{trig}_{T}<1.5$ GeV/c for centrality 0-0.2% in PbPb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV.

The $p_{T}$-dependent factorization ratio, $r_{2}$, as a function of $p^{a}_{T} - p^{b}_{T}$ for $1.5<p^{trig}_{T}<2.0$ GeV/c for centrality 0-0.2% in PbPb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV.

The $p_{T}$-dependent factorization ratio, $r_{2}$, as a function of $p^{a}_{T} - p^{b}_{T}$ for $2.0<p^{trig}_{T}<2.5$ GeV/c for centrality 0-0.2% in PbPb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV.

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Measurement of long-range near-side two-particle angular correlations in pp collisions at sqrt(s) = 13 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Rev.Lett. 116 (2016) 172302, 2016.
Inspire Record 1397173 DOI 10.17182/hepdata.73192

Results on two-particle angular correlations for charged particles produced in pp collisions at a center-of-mass energy of 13 TeV are presented. The data were taken with the CMS detector at the LHC and correspond to an integrated luminosity of about 270 inverse nanobarns. The correlations are studied over a broad range of pseudorapidity (abs(eta) < 2.4) and over the full azimuth (phi) as a function of charged particle multiplicity and transverse momentum (pt). In high-multiplicity events, a long-range (abs(Delta eta) > 2.0), near-side (Delta phi approximately 0) structure emerges in the two-particle Delta eta-Delta phi correlation functions. The magnitude of the correlation exhibits a pronounced maximum in the range 1.0 < pt < 2.0 GeV/c and an approximately linear increase with the charged particle multiplicity, with an overall correlation strength similar to that found in earlier pp data at sqrt(s) = 7 TeV. The present measurement extends the study of near-side long-range correlations up to charged particle multiplicities of N[ch] approximately 180, a region so far unexplored in pp collisions. The observed long-range correlations are compared to those seen in pp, pPb, and PbPb collisions at lower collision energies.

38 data tables

Correlated yield obtained with the ZYAM procedure as a function of $|\Delta\Phi|$, averaged over 2 $<|\Delta\eta|<$ 4 in for 0.1 $<p_{T}<$ 1.0 $GeV/c$ and $N_{offline}^{trk}<$ 35 bins for pp data at $\sqrt =$ 13 $TeV$. The $p_{T}$ selection applies to both particles in the pair. Only statistical uncertainties are given. The subtracted ZYAM constant is given ($C_{ZYAM}$).

Correlated yield obtained with the ZYAM procedure as a function of $|\Delta\Phi|$, averaged over 2 $<|\Delta\eta|<$ 4 in for 0.1 $<p_{T}<$ 1.0 $GeV/c$ and $N_{offline}^{trk}<$ 35 bins for pp data at $\sqrt =$ 7 $TeV$. The $p_{T}$ selection applies to both particles in the pair. Only statistical uncertainties are given. The subtracted ZYAM constant is given ($C_{ZYAM}$).

Correlated yield obtained with the ZYAM procedure as a function of $|\Delta\Phi|$, averaged over 2 $<|\Delta\eta|<$ 4 in for 1.0 $<p_{T}<$ 2.0 $GeV/c$ and $N_{offline}^{trk}<$ 35 bins for pp data at $\sqrt =$ 13 $TeV$. The $p_{T}$ selection applies to both particles in the pair. Only statistical uncertainties are given. The subtracted ZYAM constant is given ($C_{ZYAM}$).

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Evidence for collectivity in pp collisions at the LHC

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Lett.B 765 (2017) 193-220, 2017.
Inspire Record 1471287 DOI 10.17182/hepdata.76506

Measurements of two- and multi-particle angular correlations in pp collisions at sqrt(s) = 5, 7, and 13 TeV are presented as a function of charged-particle multiplicity. The data, corresponding to integrated luminosities of 1.0 inverse picobarn (5 TeV), 6.2 inverse picobarns (7 TeV), and 0.7 inverse picobarns (13 TeV), were collected using the CMS detector at the LHC. The second-order (v[2]) and third-order (v[3]) azimuthal anisotropy harmonics of unidentified charged particles, as well as v[2] of K0 short and Lambda/anti-Lambda particles, are extracted from long-range two-particle correlations as functions of particle multiplicity and transverse momentum. For high-multiplicity pp events, a mass ordering is observed for the v[2] values of charged hadrons (mostly pions), K0 short, and Lambda/anti-Lambda, with lighter particle species exhibiting a stronger azimuthal anisotropy signal below pt of about 2 GeV/c. For 13 TeV data, the v[2] signals are also extracted from four- and six-particle correlations for the first time in pp collisions, with comparable magnitude to those from two-particle correlations. These observations are similar to those seen in pPb and PbPb collisions, and support the interpretation of a collective origin for the observed long-range correlations in high-multiplicity pp collisions.

34 data tables

The second-order Fourier coefficients, $V_{2\Delta}(2, |\Delta\eta| > 2)$, as a function of $N_{offline}^{trk}$ for charged particles.

The second-order Fourier coefficients, $V_{2\Delta}(2, |\Delta\eta| > 2)$, as a function of $N_{offline}^{trk}$ for charged particles, after correcting for back-to-back jet correlations, estimated from the 10 $\leq$ $N_{offline}^{trk}$ < 20 range.

The second-order Fourier coefficients, $V_{3\Delta}(2, |\Delta\eta| > 2)$, as a function of $N_{offline}^{trk}$ for charged particles.

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