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Charged Multiplicity of Hadronic Events Containing Heavy Quark Jets

Rowson, P.C. ; Trilling, G. ; Abrams, G.S. ; et al.
Phys.Rev.Lett. 54 (1985) 2580-2583, 1985.
Inspire Record 212819 DOI 10.17182/hepdata.20380

The charged-particle multiplicities of hadronic events deriving from produced bottom or charm quarks have been measured in the Mark II detector at PEP in e+e− annihilation at 29GeV. For events containing one semileptonic and one hadronic weak decay, we find multiplicities of 15.2±0.5±0.7 for bottom and 13.0±0.5±0.8 for charm. The corresponding multiplicities of charged particles accompanying the pair of heavy hadrons are 5.2±0.5±0.9 for bottom, and 8.1±0.5±0.9 for charm.

7 data tables
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Measurement of inclusive momentum spectra and multiplicity distributions of charged particles at S**1/2 sim 2-5 GeV

The BES collaboration Dunwoodie, W. ; Bai, J.Z. ; Ban, Y. ; et al.
Phys.Rev. D69 (2004) 072002, 2004.
Inspire Record 622224 DOI 10.17182/hepdata.22183

Inclusive momentum spectra and multiplicity distributions of charged particles measured with BESII detector at center of mass energies of 2.2,2.6,3.0,3.2,4.6 and 4.8 GeV are presented. Values of the second binomial moment, $R_2$, obtained from the multiplicity distributions are reported. These results are compared with both experimental data from high energy $e^+e^-$, $ep$ and $p\bar{p}$ experiments and QCD calculations.

12 data tables

Measured xi =-ln(2p/sqrt(s)) spectra for centre of mass energy 2.2 GeV.. Errors are statistical and systematic added in quadrature.

Measured xi =-ln(2p/sqrt(s)) spectra for centre of mass energy 2.6 GeV.. Errors are statistical and systematic added in quadrature.

Measured xi =-ln(2p/sqrt(s)) spectra for centre of mass energy 3.0 GeV.. Errors are statistical and systematic added in quadrature.

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Measurement of the gluon fragmentation function and a comparison of the scaling violation in gluon and quark jets

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adye, T. ; et al.
Eur.Phys.J. C13 (2000) 573-589, 2000.
Inspire Record 511099 DOI 10.17182/hepdata.49028
7 data tables

Charged hadron XE(=Z) distributions. Durham algorithm. XISTAR is peak position in XI=LOG(-XE) distribution.

Charged hadron XE(=Z) distributions. Durham algorithm. XISTAR is peak position in XI=LOG(-XE) distribution.

Charged hadron XE(=Z) distributions. Durham algorithm. XISTAR is peak position in XI=LOG(-XE) distribution.

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Particle multiplicity of unbiased gluon jets from $e^{+} e^{-}$ three jet events

The OPAL collaboration
Eur.Phys.J. C23 (2002) 597-613, 2002.
Inspire Record 565517 DOI 10.17182/hepdata.49742

The charged particle multiplicities of two- and three-jet events from the reaction e+e- -> Z0 -> hadrons are measured for Z0 decays to light quark (uds) flavors. Using recent theoretical expressions to account for biases from event selection, results corresponding to unbiased gluon jets are extracted over a range of jet energies from about 11 to 30 GeV. We find consistency between these results and direct measurements of unbiased gluon jet multiplicity from upsilon and Z0 decays. The unbiased gluon jet data including the direct measurements are compared to corresponding results for quark jets. We perform fits based on analytic expressions for particle multiplicity in jets to determine the ratio r = Ng/Nq of multiplicities between gluon and quark jets as a function of energy. We also determine the ratio of slopes, r(1) = (dNg/dy)/(dNq/dy), and of curvatures, r(2) = (d2Ng/dy2)/(d2Nq/dy2), where y specifies the energy scale. At 30 GeV, we find r = 1.422 +/- 0.051, r(1) = 1.761 +/- 0.071 and r(2) = 1.98 +/- 0.13, where the uncertainties are the statistical and systematic terms added in quadrature. These results are in general agreement with theoretical predictions. In addition, we use the measurements of the energy dependence of Ng and Nq to determine an effective value of the ratio of QCD color factors, CA/CF. Our result, CA/CF = 2.23 +/- 0.14 (total), is consistent with the QCD value of 2.25.

4 data tables

Measurements of the mean charged particle multiplicity of biased two-jet uds flavour events from Z0 decays as a function of the transverse momentum cutoff PT(C=LU) used to separate two- and three-jet events.

Measurements of the mean charged particle multiplicity of three-jet uds flavour 'Y events' from Z0 decays, as a function of the angle THETA1 between the lowest two energy jets. The results for the quark jet scale SQRT(S(C=QQBAR)) and the gluon jet scales PT(C=LU) and PT(C=LE) are also given.

Measurements of the unbiased gluon multiplicity as a function of the energy scale Q=PT(C=LU). The corresponding bins of THETA1 in 'Y events' are also indicated.

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Charged particle momentum spectra in e+ e- annihilation at s**(1/2) = 192-GeV to 209-GeV

The OPAL collaboration
Eur.Phys.J. C27 (2003) 467-481, 2003.
Inspire Record 595335 DOI 10.17182/hepdata.48893

Charged particle momentum distributions are studied in the reaction e+e- -> hadrons, using data collected with the OPAL detector at centre-of-mass energies from 192 GeV to 209 GeV. The data correspond to an average centre-of- mass energy of 201.7 GeV and a total integrated luminosity of 433 pb-1. The measured distributions and derived quantities, in combination with corresponding results obtained at lower centre-of-mass energies, are compared to QCD predictions in various theoretical approaches to study the energy dependence of the strong interaction and to test QCD as the theory describing it. In general, a good agreement is found between the measurements and the corresponding QCD predictions.

5 data tables

The measured values of the PTIN distribution.

The measured values of the PTOUT distribution.

The measured values of the rapidity, YRAP, distribution.

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Measurement of charged-particle multiplicity distributions and their $H_{q}$ moments in hadronic $Z$ decays at LEP

The L3 collaboration Achard, P. ; Adriani, O. ; Aguilar-Benitez, M. ; et al.
Phys.Lett. B577 (2003) 109-119, 2003.
Inspire Record 565148 DOI 10.17182/hepdata.49796

The charged-particle multiplicity distribution is measured for all hadronic events as well as for light-quark and b-quark events produced in e+e- collisions at the Z pole. Moments of the charged-particle multiplicity distributions are calculated. The H moments of the multiplicity distributions are studied, and their quasi-oscillations as a function of the rank of the moment are investigated.

6 data tables

Moments of the charged particle multiplicity distribution with KOS and LAMBDA decay for all events.

Moments of the charged particle multiplicity distribution without KOS and LAMBDA decay for all events.

Moments of the charged particle multiplicity distribution with KOS and LAMBDA decay for light quark events.

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Charged and identified particles in the hadronic decay of W bosons and in e+ e- ---> q anti-q from 130-GeV to 200-GeV

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adye, T. ; et al.
Eur.Phys.J. C18 (2000) 203-228, 2000.
Inspire Record 526164 DOI 10.17182/hepdata.43294

Inclusive distributions of charged particles in hadronic W decays are experimentally investigated using the statistics collected by the DELPHI experiment at LEP during 1997, 1998 and 1999, at centre-of-mass energies from 183 to around 200 GeV. The possible effects of interconnection between the hadronic decays of two Ws are not observed. Measurements of the average multiplicity for charged and identified particles in q qbar and WW events at centre-of-mass energies from 130 to 200 GeV and in W decays are presented. The results on the average multiplicity of identified particles and on the position xi^* of the maximum of the xi_p = -log(2p/sqrt(s)) distribution are compared with predictions of JETSET and MLLA calculations.

16 data tables

Corrected multiplicites and dispersions of charged particles produced in hadronic decays from QQBAR events. The 200 GeV results are a weighted average fromthe 192, 196 and 200 GeV data.

Average multiplicities of identified hadrons produced in hadronic decays from QQBAR events.

Corrected multiplicites and dispersions of charged particles produced in fully hadronic W decays from two W 4Q and 2Q events.

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Consistent measurements of alpha(s) from precise oriented event shape distributions

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adye, T. ; et al.
Eur.Phys.J. C14 (2000) 557-584, 2000.
Inspire Record 522656 DOI 10.17182/hepdata.13245

An updated analysis using about 1.5 million events recorded at $\sqrt{s} = M_Z$ with the DELPHI detector in 1994 is presented. Eighteen infrared and collinear safe event shape observables are measured as a function of the polar angle of the thrust axis. The data are compared to theoretical calculations in ${\cal O} (\alpha_s^2)$ including the event orientation. A combined fit of $\alpha_s$ and of the renormalization scale $x_{\mu}$ in $\cal O(\alpha_s^2$) yields an excellent description of the high statistics data. The weighted average from 18 observables including quark mass effects and correlations is $\alpha_s(M_Z^2) = 0.1174 \pm 0.0026$. The final result, derived from the jet cone energy fraction, the observable with the smallest theoretical and experimental uncertainty, is $\alpha_s(M_Z^2) = 0.1180 \pm 0.0006 (exp.) \pm 0.0013 (hadr.) \pm 0.0008 (scale) \pm 0.0007 (mass)$. Further studies include an $\alpha_s$ determination using theoretical predictions in the next-to-leading log approximation (NLLA), matched NLLA and $\cal O(\alpha_s^2$) predictions as well as theoretically motivated optimized scale setting methods. The influence of higher order contributions was also investigated by using the method of Pad\'{e} approximants. Average $\alpha_s$ values derived from the different approaches are in good agreement.

33 data tables

The weighted value of ALPHA-S from all the measured observables using experimentally optimized renormalization scale values and corrected for the b-mass toleading order.

The value of ALPHA-S derived from the JCEF and corrected for heavy quark mass effects. The quoted errors are respectively due to experimental error, hadronization, renormalization scale and heavy quark mass correction uncertainties.

Energy Energy Correlation EEC.

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Studies of QCD in e+ e- ---> hadrons at E(cm) = 130-GeV and 136-GeV

The ALEPH collaboration Buskulic, D. ; De Bonis, I. ; Decamp, D. ; et al.
Z.Phys. C73 (1997) 409-420, 1997.
Inspire Record 421546 DOI 10.17182/hepdata.47802
8 data tables

Inclusive charged particle distribution as a function of XP.

Inclusive charged particle distribution as a function of rapidity (YRAP).

Inclusive charged particle distribution as a function of PT in the event plane.

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The Scale dependence of the hadron multiplicity in quark and gluon jets and a precise determination of C(A) / C(F)

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adye, T. ; et al.
Phys.Lett. B449 (1999) 383-400, 1999.
Inspire Record 495414 DOI 10.17182/hepdata.49173

Data collected at the Z resonance using the DELPHI detector at LEP are used to determine the charged hadron multiplicity in gluon and quark jets as a function of a transverse momentum-like scale. The colour factor ratio, \cacf, is directly observed in the increase of multiplicities with that scale. The smaller than expected multiplicity ratio in gluon to quark jets is understood by differences in the hadronization of the leading quark or gluon. From the dependence of the charged hadron multiplicity on the opening angle in symmetric three-jet events the colour factor ratio is measured to be: C_A/C_F = 2.246 \pm 0.062 (stat.) \pm 0.080 (syst.) \pm 0.095 (theo.)

3 data tables

Charged multiplicity in events with a hard photon, as a function of the apparent centre-of-mass energy (SQRT(S)) of the hadronic system. The errors shown are statistical only.

Charged multiplicity in symmetric three jet events as function of the opening angle between the low energetic jets, THETA1. Jets are defined from charged and neutral particles using the DURHAM algorithm. The errors shown are statistical only.

Twice the difference of the multiplicity in three jet events and in qqbar events of comparable scale 2(N_3jet-N_qqbar). The three-jet event multiplicity isequal to the data of Fig. 3c), the qqbar-multiplicity is taken from a fit of th e e+e- data corrected for the varying b-quark contribution. This multiplicity can be identified with the multiplicity of a hypothetical gluon-gluon event. Thereis a normalization uncertainty (i.e. a scale independent constant) of the gluon -gluon event multiplicity which should not influence the slope of the gg-multiplicity with scale (see paper). The errors shown are statistical only.


pi+-, K+-, p and anti-p production in Z0 ---> q anti-q, Z0 ---> b anti-b, Z0 ---> u anti-u, d anti-d, s anti-s

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adye, T. ; et al.
Eur.Phys.J. C5 (1998) 585-620, 1998.
Inspire Record 473409 DOI 10.17182/hepdata.49385
39 data tables

Mean particle multiplicities for Z0-->Q-QBAR events. The second systematic (DSYS) error is due to the extrapolation of the differential distributions to the full kinematic range.

Mean particle multiplicities for Z0-->B-BBAR events. The second systematic (DSYS) error is due to the extrapolation of the differential distributions to the full kinematic range.

Mean particle multiplicities for Z0-->(U-UBAR,D-DBAR,S-SBAR) events. The second systematic (DSYS) error is due to the extrapolation of the differential distributions to the full kinematic range.

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Charged particle multiplicities of quark and gluon jets in e+ e- annihilation at TRISTAN

The TOPAZ collaboration Nakabayashi, K. ; Yamauchi, M. ; Abe, K. ; et al.
Phys.Lett. B413 (1997) 447-452, 1997.
Inspire Record 454183 DOI 10.17182/hepdata.28238
4 data tables

No description provided.

Multiplicity measured for events with a Thrust of 2/3. These are three-foldsymmetric events.

Mean charged particle multiplicity as function of -log(1-THRUST).

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Measurement of the average lifetime of $b$ hadrons in $Z$ decays

The L3 collaboration Acciarri, M. ; Adriani, O. ; Aguilar-Benitez, M. ; et al.
Phys.Lett. B416 (1998) 220-232, 1998.
Inspire Record 449593 DOI 10.17182/hepdata.47380
2 data tables

No description provided.

No description provided.


Charged particle multiplicity in e+ e- ---> q anti-q events at 161-GeV and 172-GeV and from the decay of the W boson

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adye, T. ; et al.
Phys.Lett. B416 (1998) 233-246, 1998.
Inspire Record 449290 DOI 10.17182/hepdata.47398
3 data tables

No description provided.

No description provided.

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. C75 (1997) 193-207, 1997.
Inspire Record 440721 DOI 10.17182/hepdata.47487
26 data tables

Determination of alpha_s.

Multiplicity and higher moments.

Thrust distribution.

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Measurement of event shape and inclusive distributions at S**(1/2) = 130-GeV and 136-GeV

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adye, T. ; et al.
Z.Phys. C73 (1997) 229-242, 1997.
Inspire Record 424629 DOI 10.17182/hepdata.47715
26 data tables

mean values for event shape variables.

Integral of event shape distribution over the specified interval.

Integral of event shape distribution over the specified interval.

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Test of QCD analytic predictions for the multiplicity ratio between gluon and quark jets

The OPAL collaboration Alexander, G. ; Allison, John ; Altekamp, N. ; et al.
Phys.Lett. B388 (1996) 659-672, 1996.
Inspire Record 423486 DOI 10.17182/hepdata.47714
2 data tables

Mean charged particle multiplicity in gluon jets.

Mean charged particle multiplicity in single hemisphere light quark jets.


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. C72 (1996) 191-206, 1996.
Inspire Record 418007 DOI 10.17182/hepdata.47564
23 data tables

Determination of alpha_s.

Multiplicity and high moments.

Tmajor distribution.

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Study of the structure of hadronic events and determination of alpha-s at s**(1/2) = 130-GeV and 136-GeV

The L3 collaboration Acciarri, M. ; Adam, A. ; Adriani, O. ; et al.
Phys.Lett. B371 (1996) 137-148, 1996.
Inspire Record 404916 DOI 10.17182/hepdata.48010
3 data tables

Mean values of the event shape variables.

Mean charged particle multiplicity.

The value of alpha_s from the fits to the event shape variables : thrust (THRUST), scale heavy jet mass (MH**2/S), total jet broadening (BT)and wide jet broadening (BW). The last value is combined result (COMBINED). The second systematic error is due to uncertainties in the theory.


Charged particle multiplicity in e+ e-interactions at s**(1/2) = 130-GeV

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adye, T. ; et al.
Phys.Lett. B372 (1996) 172-180, 1996.
Inspire Record 415744 DOI 10.17182/hepdata.47831
1 data table

No description provided.


A Study of coherence of soft gluons in hadron jets

The OPAL collaboration Akrawy, M.Z. ; Alexander, G. ; Allison, J. ; et al.
Phys.Lett. B247 (1990) 617-628, 1990.
Inspire Record 297564 DOI 10.17182/hepdata.49561
1 data table

Statistical errors only. Overall systematic error of 5%.


Measurement of the longitudinal, transverse and asymmetry fragmentation functions at LEP

The OPAL collaboration Akers, R. ; Alexander, G. ; Allison, John ; et al.
Z.Phys. C68 (1995) 203-214, 1995.
Inspire Record 395450 DOI 10.17182/hepdata.48040
4 data tables

Transverse component of the fragmentation function.

Longitudinal component of the fragmentation function.

Asymmetry component of the fragmentation function.

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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. B357 (1995) 487-499, 1995.
Inspire Record 398195 DOI 10.17182/hepdata.47843
4 data tables

No description provided.

No description provided.

No description provided.

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Measurements of the charged particle multiplicity distribution in restricted rapidity intervals

The ALEPH collaboration Buskulic, D. ; Casper, D. ; De Bonis, I. ; et al.
Z.Phys. C69 (1995) 15-26, 1995.
Inspire Record 396889 DOI 10.17182/hepdata.48009
6 data tables

Unfolded charged particle multiplicity distribution given the probability to have an hadronic Z0 decay with MULT charged particles.

Unfolded multiplicity distributions for restricted rapidity bin <= 0.5 along the thrust axis.

Unfolded multiplicity distributions for restricted rapidity bin <= 1.0 along the thrust axis.

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Production of charged particles, K0(s), K+-, p and Lambda in Z --> b anti-b events and in the decay of b hadrons

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adye, T. ; et al.
Phys.Lett. B347 (1995) 447-466, 1995.
Inspire Record 392257 DOI 10.17182/hepdata.48180
9 data tables

Event multiplicity in bottom events.

Differential cross section for charged particles in BOTTOM tagged hemispheres.

Differential cross section for charged particles in untagged hemispheres.

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