Date

Measurement of Jet Production Cross Sections in Deep-inelastic $ep$ Scattering at HERA

The H1 collaboration Andreev, V. ; Baghdasaryan, A. ; Andreev, Vladimir ; et al.
Eur.Phys.J.C 77 (2017) 215, 2017.
Inspire Record 1496981 DOI 10.17182/hepdata.86390

A precision measurement of jet cross sections in neutral current deep-inelastic scattering for photon virtualities $5.5

55 data tables

Inclusive jet cross sections measured as a function of $P_T^{\rm jet}$ for $Q^2$ = 5.5-8.0 GeV$^2$. The correction factors on the theoretical cross sections $c^{\rm had}$ are listed together with their uncertainties. The radiative correction factors $c^{\rm rad}$ are already included in the quoted cross sections. Note that the uncertainties labelled $\delta^{E_{e^\prime}}$ and $\delta^{\theta_{e^\prime}}$ in Table 6 of the paper (arXiv:1611.03421v3) should be swapped. See Table 5 of arXiv:1406.4709v2 for details of the correlation model.

Inclusive jet cross sections measured as a function of $P_T^{\rm jet}$ for $Q^2$ = 8.0-11.0 GeV$^2$. The correction factors on the theoretical cross sections $c^{\rm had}$ are listed together with their uncertainties. The radiative correction factors $c^{\rm rad}$ are already included in the quoted cross sections. Note that the uncertainties labelled $\delta^{E_{e^\prime}}$ and $\delta^{\theta_{e^\prime}}$ in Table 6 of the paper (arXiv:1611.03421v3) should be swapped. See Table 5 of arXiv:1406.4709v2 for details of the correlation model.

Inclusive jet cross sections measured as a function of $P_T^{\rm jet}$ for $Q^2$ = 11.0-16.0 GeV$^2$. The correction factors on the theoretical cross sections $c^{\rm had}$ are listed together with their uncertainties. The radiative correction factors $c^{\rm rad}$ are already included in the quoted cross sections. Note that the uncertainties labelled $\delta^{E_{e^\prime}}$ and $\delta^{\theta_{e^\prime}}$ in Table 6 of the paper (arXiv:1611.03421v3) should be swapped. See Table 5 of arXiv:1406.4709v2 for details of the correlation model.

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A measurement of the b-quark mass from hadronic Z decays.

The ALEPH collaboration Barate, R. ; Decamp, D. ; Ghez, Philippe ; et al.
Eur.Phys.J.C 18 (2000) 1-13, 2000.
Inspire Record 531468 DOI 10.17182/hepdata.49909

Hadronic Z decay data taken with the ALEPH detector at LEP1 are used to measure the three-jet rate as well as moments of various event-shape variables. The ratios of the observables obtained from b-tagged events and from an inclusive sample are determined. The mass of the b quark is extracted from a fit to the measured ratios using a next-to-leading order prediction including mass effects. Taking the first moment of the y3 distribution, which is the observable with the smallest hadronization corrections and systematic uncertainties, the result is: mb(MZ) = [3.27+-0.22(stat) +-0.22(exp)+-0.38(had)+-0.16(theo)] GeV/c2. The measured ratio is alternatively employed to test the flavour independence of the strong coupling constant for b and light quarks.

1 data table

No description provided.


QCD analyses and determinations of alpha(s) in e+ e- annihilation at energies between 35-GeV and 189-GeV.

The JADE & OPAL collaborations Pfeifenschneider, P. ; Biebel, O. ; Movilla Fernandez, P.A. ; et al.
Eur.Phys.J.C 17 (2000) 19-51, 2000.
Inspire Record 513337 DOI 10.17182/hepdata.12882

We employ data taken by the JADE and OPAL experiments for an integrated QCD study in hadronic e+e- annihilations at c.m.s. energies ranging from 35 GeV through 189 GeV. The study is based on jet-multiplicity related observables. The observables are obtained to high jet resolution scales with the JADE, Durham, Cambridge and cone jet finders, and compared with the predictions of various QCD and Monte Carlo models. The strong coupling strength, alpha_s, is determined at each energy by fits of O(alpha_s^2) calculations, as well as matched O(alpha_s^2) and NLLA predictions, to the data. Matching schemes are compared, and the dependence of the results on the choice of the renormalization scale is investigated. The combination of the results using matched predictions gives alpha_s(MZ)=0.1187+{0.0034}-{0.0019}. The strong coupling is also obtained, at lower precision, from O(alpha_s^2) fits of the c.m.s. energy evolution of some of the observables. A qualitative comparison is made between the data and a recent MLLA prediction for mean jet multiplicities.

80 data tables

Overall result for ALPHAS at the Z0 mass from the combination of the ln R-matching results from the observables evolved using a three-loop running expression. The errors shown are total errors and contain all the statistics and systematics.

Weighted mean for ALPHAS at the Z0 mass determined from the energy evolutions of the mean values of the 2-jet cross sections obtained with the JADE and DURHAMschemes and the 3-jet fraction for the JADE, DURHAM and CAMBRIDGE schemes evaluted at a fixed YCUT.. The errors shown are total errors and contain all the statistics and systematics.

Combined results for ALPHA_S from fits of matched predicitions. The first systematic (DSYS) error is the experimental systematic, the second DSYS error isthe hadronization systematic and the third is the QCD scale error. The values of ALPHAS evolved to the Z0 mass using a three-loop evolution are also given.

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QCD studies with e+ e- annihilation data at 172-GeV to 189-GeV.

The OPAL collaboration Abbiendi, G. ; Ackerstaff, K. ; Akesson, P.F. ; et al.
Eur.Phys.J.C 16 (2000) 185-210, 2000.
Inspire Record 513476 DOI 10.17182/hepdata.49000

We have studied hadronic events from e+e- annihilation data at centre-of-mass energies of sqrt{s}=172, 183 and 189 GeV. The total integrated luminosity of the three samples, measured with the OPAL detector, corresponds to 250 pb^-1. We present distributions of event shape variables, charged particle multiplicity and momentum, measured separately in the three data samples. From these we extract measurements of the strong coupling alpha_s, the mean charged particle multiplicity and the peak position xi_0 in the xi_p=ln(1/x_p) distribution. In general the data are described well by analytic QCD calculations and Monte Carlo models. Our measured values of alpha_s, and xi_0 are consistent with previous determinations at sqrt{s}=MZ.

20 data tables

Distribution of Thrust.

Distribution of Thrust Major.

Distribution of Thrust Minor.

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Test of the flavour independence of alpha(s) using next-to-leading order calculations for heavy quarks.

The OPAL collaboration Abbiendi, G. ; Ackerstaff, K. ; Alexander, G. ; et al.
Eur.Phys.J.C 11 (1999) 643-659, 1999.
Inspire Record 498246 DOI 10.17182/hepdata.49192

We present a test of the flavour independence of the strong coupling constant for charm and bottom quarks with respect to light (uds) quarks, based on a hadronic event sample obtained with the OPAL detector at LEP. Five observables related to global event shapes were used to measure alpha_s in three flavour tagged samples (uds, c and b). The event shape distributions were fitted by Order(alpha_s**2) calculations of jet production taking into account mass effects for the c and b quarks. We find: = 0.997 +- 0.038(stat.) +- 0.030(syst.) +- 0.012(theory) and = 0.993 +- 0.008(stat.) +- 0.006(syst.) +- 0.011(theory) for the ratios alpha_s(charm)/alpha_s(uds) and alpha_s(b)/alpha_s(uds) respectively.

1 data table

No description provided.


QCD studies with e+ e- annihilation data at 161-GeV.

The OPAL collaboration Ackerstaff, K. ; Alexander, G. ; Allison, John ; et al.
Z.Phys.C 75 (1997) 193-207, 1997.
Inspire Record 440721 DOI 10.17182/hepdata.47487

We have studied hadronic events produced at LEP at a centre-of-mass energy of 161 GeV. We present distributions of event shape variables, jet rates, charged particle momentum spectra and multiplicities. We determine the strong coupling strength to be αs(161 GeV) = 0.101±0.005(stat.)±0.007(syst.), the mean charged particle multiplicity to be 〈nch〉(161 GeV) = 24.46 ± 0.45(stat.) ± 0.44(syst.) and the position of the peak in the ξp = ln(1/xp) distribution to be ξ0(161 GeV) = 4.00 ±0.03(stat.)±0.04(syst.). These results are compared to data taken at lower centre-of-mass energies and to analytic QCD or Monte Carlo predictions. Our measured value of αs(161 GeV) is consistent with other measurements of αs. Within the current statistical and systematic uncertainties, the PYTHIA, HERWIG and ARIADNE QCD Monte Carlo models and analytic calculations are in overall agreement with our measurements. The COJETS QCD Monte Carlo is in general agreement with the data for momentum weighted distributions like Thrust, but predicts a significantly larger charged particle multiplicity than is observed experimentally.

26 data tables

Determination of alpha_s.

Multiplicity and higher moments.

Thrust distribution.

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QCD studies with e+ e- annihilation data at 130-GeV and 136-GeV.

The OPAL collaboration Alexander, G. ; Allison, John ; Altekamp, N. ; et al.
Z.Phys.C 72 (1996) 191-206, 1996.
Inspire Record 418007 DOI 10.17182/hepdata.47564

We have studied hadronic events produced at LEP at centre-of-mass energies of 130 and 136 GeV. Distributions of event shape observables, jet rates, momentum spectra and multiplicities are presented and compared to the predictions of several Monte Carlo models and analytic QCD calculations. From fits of event shape and jet rate distributions to\({\mathcal{O}}(\alpha _s^2 ) + NLLA\) QCD calculations, we determineαs(133 GeV)=0.110±0.005(stat.)±0.009(syst.). We measure the mean charged particle multiplicity 〈nch〉=23.40±0.45(stat.) ±0.47(syst.) and the position ζ0 of the peak in the ζp = ln(1/xp) distribution ζ0=3.94±0.05(stat.)±0.11(syst.). These results are compared to lower energy data and to analytic QCD or Monte Carlo predictions for their energy evolution.

23 data tables

Determination of alpha_s.

Multiplicity and high moments.

Tmajor distribution.

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Measurement of alpha-s from scaling violations in fragmentation functions in e+ e- annihilation

The ALEPH collaboration Buskulic, D. ; Casper, D. ; De Bonis, I. ; et al.
Phys.Lett.B 357 (1995) 487-499, 1995.
Inspire Record 398195 DOI 10.17182/hepdata.47843

A study of scaling violations in fragmentation functions performed by the ALEPH collaboration at LEP is presented. Data samples enriched in uds, c, b and gluon jets, respectively, together with measurements of the longitudinal and transverse inclusive cross sections are used to extract the fragmentation function for the gluon and for each flavour. The measurements are compared to data from experiments at energies between 22 GeV and 91 GeV and scaling violations consistent with QCD predictions are observed. From this, a measurement of the strong coupling constant α s ( Mz ) = 0.126 ±0.009 is obtained.

4 data tables

No description provided.

No description provided.

No description provided.

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Test of the flavor independence of alpha-s

The ALEPH collaboration Buskulic, D. ; Casper, D. ; De Bonis, I. ; et al.
Phys.Lett.B 355 (1995) 381-393, 1995.
Inspire Record 393416 DOI 10.17182/hepdata.48177

Using about 950000 hadronic events collected during 1991 and 1992 with the ALEPH detector, the ratios r b = α s b α s udsc and r uds = α s uds α s cb have been measured in order to test the flavour independence of the strong coupling constant α s . The analysis is based on event-shape variables using the full hadronic sample, two b -quark samples enriched by lepton tagging and lifetime tagging, and a light-quark sample enriched by lifetime antitagging. The combined results are r b = 1.002±0.023 and r uds = 0.971 ± 0.023.

1 data table

No description provided.


Determination of the strong coupling constant from jet rates in deep inelastic scattering

The H1 collaboration Ahmed, T. ; Aid, S. ; Andreev, V. ; et al.
Phys.Lett.B 346 (1995) 415-425, 1995.
Inspire Record 380945 DOI 10.17182/hepdata.45050

Jet rates in deep inelastic electron proton scattering are studied with the H1 detector at HERA for momentum transfers squared between 10 and 4000 GeV 2 . It is shown that they can be quantitatively described by perturbative QCD in next to leading order making use of the parton densities of the proton and with the strong coupling constant α s as a free parameter. The measured value, α s ( M Z 2 ) = 0.123 ± 0.018, is in agreement both with determinations from e + e − annihilation at LEP using the same observable and with the world average.

1 data table

Determination of ALP_S(MZ**2). Error contains both statistics and systematics.