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Measurements of the production cross-section for a $Z$ boson in association with $b$- or $c$-jets in proton-proton collisions at $\sqrt{s} = 13$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Aakvaag, Erlend ; Abbott, Braden Keim ; et al.
Eur.Phys.J.C 84 (2024) 984, 2024.
Inspire Record 2771257 DOI 10.17182/hepdata.151815

This paper presents a measurement of the production cross-section of a $Z$ boson in association with $b$- or $c$-jets, in proton-proton collisions at $\sqrt{s} = 13$ TeV with the ATLAS experiment at the Large Hadron Collider using data corresponding to an integrated luminosity of 140 fb$^{-1}$. Inclusive and differential cross-sections are measured for events containing a $Z$ boson decaying into electrons or muons and produced in association with at least one $b$-jet, at least one $c$-jet, or at least two $b$-jets with transverse momentum $p_\textrm{T} > 20$ GeV and rapidity $|y| < 2.5$. Predictions from several Monte Carlo generators based on next-to-leading-order matrix elements interfaced with a parton-shower simulation, with different choices of flavour schemes for initial-state partons, are compared with the measured cross-sections. The results are also compared with novel predictions, based on infrared and collinear safe jet flavour dressing algorithms. Selected $Z + \ge 1 c$-jet observables, optimized for sensitivity to intrinsic-charm, are compared with benchmark models with different intrinsic-charm fractions.

29 data tables

Figure 6(left) of the article. Measured fiducial cross sections for events with $Z (\rightarrow ll) \ge 1 $ b-jets. The thin inner band corresponds to the statistical uncertainty of the data, and the outer band to statistical and systematic uncertainties of the data, added in quadrature.

Figure 6(right) of the article. Measured fiducial cross sections for events with $Z (\rightarrow ll) \ge 2 $ b-jets. The thin inner band corresponds to the statistical uncertainty of the data, and the outer band to statistical and systematic uncertainties of the data, added in quadrature.

Figure 7 of the article. Measured fiducial cross sections for events with $Z (\rightarrow ll) \ge 1 $ c-jets. The thin inner band corresponds to the statistical uncertainty of the data, and the outer band to statistical and systematic uncertainties of the data, added in quadrature.

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Measurement of Upsilon production for p+p and p+d interactions at 800-GeV

The NuSea collaboration Zhu, L.Y. ; Reimer, Paul E. ; Mueller, B.A. ; et al.
Phys.Rev.Lett. 100 (2008) 062301, 2008.
Inspire Record 763967 DOI 10.17182/hepdata.42715

We report a high statistics measurement of Upsilon production with an 800 GeV/c proton beam on hydrogen and deuterium targets. The dominance of the gluon-gluon fusion process for Upsilon production at this energy implies that the cross section ratio, $\sigma (p + d \to \Upsilon) / 2\sigma (p + p\to \Upsilon)$, is sensitive to the gluon content in the neutron relative to that in the proton. Over the kinematic region 0 < x_F < 0.6, this ratio is found to be consistent with unity, in striking contrast to the behavior of the Drell-Yan cross section ratio $\sigma(p+d)_{DY}/2\sigma(p+p)_{DY}$. This result shows that the gluon distributions in the proton and neutron are very similar. The Upsilon production cross sections are also compared with the p+d and p+Cu cross sections from earlier measurements.

4 data tables

Differential cross section per nucleon as a function of Feynman X for UPSILON production on the DEUT target.

Differential cross section per nucleon as a function of Feynman X for UPSILON production on the P target.

Differential cross section per nucleon as a function of transverse momentum for UPSILON production on the DEUT target.

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Production of J / psi mesons in p Be collisions at 530-GeV/c and 800-GeV/c

The E672 & E706 collaborations Gribushin, A. ; Abramov, V. ; Antipov, Yu. ; et al.
Phys.Rev.D 62 (2000) 012001, 2000.
Inspire Record 508006 DOI 10.17182/hepdata.42099

We report on the production of J/psi mesons in 530 and 800 GeV/c proton - Be collisions in the Feynman-x range 0.0 < xf < 0.6. The J/psi mesons were detected via decays into opposite sign muon pairs. Differential distributions for J/psi production have been measured as functions of xf, pT^2, and cosine of the Gottfried-Jackson decay angle. These distributions are compared with results on J/psi production obtained in 515 GeV/c pion - Be collisions, measured by the same experiment, as well as with results from other experiments using incident protons.

6 data tables

Differential XL distribution for J/PSI production in 530 GeV pBe collisions. Errors are combined statistics and systematics.

Differential PT**2 distribution for J/PSI production in 530 GeV pBe collisions. Errors are combined statistics and systematics.

Differential COS(THETA) distribution for J/PSI production in 530 GeV pBe collisions. Errors are combined statistics and systematics.

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Production of J / psi and psi (2S) mesons in pi- Be collisions at 515-GeV/c

The E672 & E706 collaborations Gribushin, A. ; Abramov, V. ; Antipov, Yu. ; et al.
Phys.Rev.D 53 (1996) 4723-4733, 1996.
Inspire Record 401108 DOI 10.17182/hepdata.42344

We have studied the production of J/ψ and ψ(2S) charmonium mesons in 515 GeV/c π−Be collisions in the Feynman-x range 0.1

7 data tables

Statistical errors only. Normalization uncertainty is 12%.

Statistical errors only. Normalization uncertainty is 12%.

Statistical errors only. Normalization uncertainty is 12%.. Theta is the angle between the MU+ and the beam axis in the J/PSI restframe (Gottfried-Jackson decay angle).

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Experimental Study of Inclusive Muon Spectra at PETRA

The Aachen-DESY-Annecy(LAPP)-MIT-NIKHEF-Beijing collaboration Adeva, B. ; Barber, D.P. ; Becker, U. ; et al.
Phys.Rev.Lett. 51 (1983) 443, 1983.
Inspire Record 13422 DOI 10.17182/hepdata.20492

The results of a high-statistics study of inclusive muon spectra at PETRA are reported. Improved mass limits have been obtained for heavy quarks, heavy leptons, and charged Higgs particles. It is shown that the fragmentation properties of b quarks and c quarks are different, with the mean fragmentation variables 〈zb〉=0.75±0.03±0.06, 〈zc〉=0.46±0.02±0.05 and the average semileptonic branching ratio for the B and C hadrons R(B)=(10.5±1.5±1.3)%, R(C)=(11.5±1.0±1.7)%.

5 data tables

No description provided.

No description provided.

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