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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Search for heavy resonances decaying to b quarks in proton-proton collisions at sqrt s=13 TeV

The CMS collaboration
CMS-PAS-EXO-20-008, 2021.
Inspire Record 1920627 DOI 10.17182/hepdata.127768

Searches are performed for resonances decaying to two jets, with at least one jet originating from a b quark, in proton-proton collisions at $\sqrt{s}=13$ TeV. The dataset corresponds to an integrated luminosity of 137 fb$^{-1}$ collected by the CMS detector at the LHC. Jets are identified as containing energetic b hadrons using a deep neural network b tagger. The invariant mass spectrum of b-tagged dijets is well described by a smooth parameterization and no evidence for the production of new particles is observed. Cross-section upper limits are set on resonances decaying into b quarks. These limits exclude at $95\%$ confidence level models of Z' bosons with a mass less than 2.4 TeV, and an excited b quark with mass less than 4.0 TeV.

19 data tables

Signal shapes of b* from the process bg$\rightarrow$b∗$\rightarrow$bg. Shown are the wide jets used to reconstruct the dijet mass spectra.

The acceptance times efficiency of the event selection for a Z'$\rightarrow$bb resonance as a function of the resonance mass.

The differential cross sections as a function of the dijet mass for the double b tagging category during 2016.

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Version 2
Observation of triple $J/\psi$ meson production in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration
CMS-PAS-BPH-21-004, 2021.
Inspire Record 1920689 DOI 10.17182/hepdata.114984

The first observation of the combined production of three $\mathrm{J}\mspace{-2mu}/\mspace{-2mu}\psi$ mesons in proton-proton collisions at a center-of-mass energy of $13\,\mathrm{TeV}$ is reported. The analysis is based on a data sample recorded by the CMS experiment at the CERN LHC corresponding to an integrated luminosity of $133\,\mathrm{fb}^{-1}$. The search for triple-$\mathrm{J}\mspace{-2mu}/\mspace{-2mu}\psi$ production is performed in final states with three $\mu^{+}\mu^{-}$ pairs that pass fiducial kinematic criteria chosen so as to select high-$p_\mathrm{T}$ $\mathrm{J}\mspace{-2mu}/\mspace{-2mu}\psi$ mesons produced at midrapidity. The $\mathrm{pp}\to\mathrm{J}\mspace{-2mu}/\mspace{-2mu}\psi\,\mathrm{J}\mspace{-2mu}/\mspace{-2mu}\psi\,\mathrm{J}\mspace{-2mu}/\mspace{-2mu}\psi\,\mathrm{X}$ process is observed with a significance in excess of five standard deviations. The fiducial cross section for this process is found to be $\sigma(\mathrm{pp}\to\mathrm{J}\mspace{-2mu}/\mspace{-2mu}\psi\,\mathrm{J}\mspace{-2mu}/\mspace{-2mu}\psi\,\mathrm{J}\mspace{-2mu}/\mspace{-2mu}\psi\,\mathrm{X})= 272^{+141}_{-104} \mathrm{(stat)} \pm 17 \mathrm{(syst)} \,\mathrm{fb}$. The result is compared to theoretical expectations for the production of three $\mathrm{J}\mspace{-2mu}/\mspace{-2mu}\psi$ mesons in single (SPS), double- (DPS), and triple- (TPS) parton scattering processes. Under the most economical assumption of factorization of multiple hard scattering probabilities in terms of SPS cross sections, the measured final state is found to be dominated by DPS and TPS contributions. A value of the associated DPS effective cross section parameter of $\sigma_\mathrm{eff,DPS} = 2.7 ^{+1.4}_{-1.0} \mathrm{(exp)} ^{+1.5}_{-1.0}\mathrm{(theo)}\,\mathrm{mb}$, related to the transverse distribution of partons in the proton, is derived.

3 data tables

Dimuon invariant mass ($m$), proper decay-length ($L$), transverse momentum ($p_{T}$), rapidity ($y$), and azimuthal angle ($\phi$) of each of the three $J/\psi$ candidates measured in the six triple-$J/\psi$ events passing our selection criteria.

Measured DPS effective cross section

$pp \rightarrow J/\psi J/\psi J/\psi X~$ fiducial cross section


Version 4
Observation of $\mathrm{B}^0\to\psi\mathrm{(2S)}\mathrm{K}^0_{\mathrm S}\pi^+\pi^-$ and $\mathrm{B}^0_{\mathrm s}\to\psi\mathrm{(2S)}\mathrm{K}^0_{\mathrm S}$ decays

The CMS collaboration
CMS-PAS-BPH-18-004, 2021.
Inspire Record 1920649 DOI 10.17182/hepdata.114370

Using a data sample corresponding to an integrated luminosity of $103.7~\mathrm{fb}^{-1}$ of pp collisions, collected by the CMS experiment at $\sqrt {s}=13~\mathrm{TeV}$ in 2017 - 2018, the $B^0 \to \psi(2S) \mathrm{K}^0_{\mathrm S}\pi^+\pi^-$ and $B^0_{s} \to\ \psi\mathrm{(2S)}\mathrm{K}^0_{\mathrm S}$ decays are observed. Measurements of their branching fractions, relative to the $\mathrm{B}^0\to\psi\mathrm{(2S)}\mathrm{K}^0_{\mathrm S}$ decay, are reported.

3 data tables

The measured branching fraction ratios

Transverse momentum distribution for B-candidate

The measured branching fractions