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Charged particle multiplicities in nuclear collisions at 200-GeV/N

The NA35 collaboration Bächler, J. ; Bartke, J. ; Bialkowska, H. ; et al.

Z.Phys.C 51 (1991) 157-162, 1991.

Inspire Record 320907 DOI 10.17182/hepdata.14983

Data on multiplicities of charged particles produced in proton-nucleus and nucleus-nucleus collisions at 200 GeV per nucleon are presented. It is shown that the mean multiplicity of negative particles is proportional to the mean number of nucleons participating in the collision both for nucleus-nucleus and proton-nucleus collisions. The apparent consistency of pion multiplicity data with the assumption of an incoherent superposition of nucleon-nucleon collisions is critically discussed.

4 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Higher Moments of Net-proton Multiplicity Distributions at RHIC

The STAR collaboration Aggarwal, M.M. ; Ahammed, Z. ; Alakhverdyants, A.V. ; et al.

Phys.Rev.Lett. 105 (2010) 022302, 2010.

Inspire Record 853304 DOI 10.17182/hepdata.73344

We report the first measurements of the kurtosis (\kappa), skewness (S) and variance (\sigma^2) of net-proton multiplicity (N_p - N_pbar) distributions at midrapidity for Au+Au collisions at \sqrt(s_NN) = 19.6, 62.4, and 200 GeV corresponding to baryon chemical potentials (\mu_B) between 200 - 20 MeV. Our measurements of the products \kappa \sigma^2 and S \sigma, which can be related to theoretical calculations sensitive to baryon number susceptibilities and long range correlations, are constant as functions of collision centrality. We compare these products with results from lattice QCD and various models without a critical point and study the \sqrt(s_NN) dependence of \kappa \sigma^2. From the measurements at the three beam energies, we find no evidence for a critical point in the QCD phase diagram for \mu_B below 200 MeV.

40 data tables

Table 1

$\Delta N_p$ multiplicity distribution in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV for 0-5 percent central collisions at midrapidity (| y |< 0.5).

Table 2

$\Delta N_p$ multiplicity distribution in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV for 30-40 percent central collisions at midrapidity (| y |< 0.5).

Table 3

$\Delta N_p$ multiplicity distribution in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV for 70-80 percent central collisions at midrapidity (| y |< 0.5).

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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

Table 1

Table 2

Table 3

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Cumulative production of pi- mesons in pi C interactions at 40-GeV/c

Baatar, Ts. ; Batsaikhan, Ts. ; Ivanovskaya, I.A. ; et al.

Sov.J.Nucl.Phys. 52 (1990) 504-508, 1990.

Inspire Record 299082 DOI 10.17182/hepdata.38727

None

7 data tables

Table 1

HERE XL IS CUMULATIVE NUMBER, DEFINED AS FOLLOWS: (E-PL)/M(NUCLEON). THE DISTRIBUTION (1/N)*D(N)/D(XL) WAS FITTED BY THE SUM: CONST(1)* EXP(-SLOPE(1)*XL)+CONST(2)*EXP(-SLOPE(2)*XL).

Table 2

HERE XL IS CUMULATIVE NUMBER, DEFINED AS FOLLOWS: (E-PL)/M(NUCLEON). THE DISTRIBUTION (XL/N)*D(N)/D(XL) WAS FITTED BY THE SUM: CONST(1)* EXP(-SLOPE(1)*XL)+CONST(2)*EXP(-SLOPE(2)*XL).

Table 3

HERE XL IS CUMULATIVE NUMBER, DEFINED AS FOLLOWS: (E-PL)/M(NUCLEON).

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EXCLUSIVE MEASUREMENTS OF LIGHT FRAGMENT PRODUCTION AT FORWARD ANGLES IN Ne - Pb AND Ne - NaF COLLISIONS AT E/A = 400-MeV AND 800-MeV

Bastid, N. ; Alard, J.P. ; Arnold, J. ; et al.

Nucl.Phys.A 506 (1990) 637-654, 1990.

Inspire Record 25478 DOI 10.17182/hepdata.36887

Emission of light fragments at small angles is studied in relativistic heavy ion collisions using the Diogene plastic wall for both symmetrical and non-symmetrical target-projectile systems with 400 MeV per nucleon and 800 MeV per nucleon incident neon nuclei. Efficiency of multiplicity measurements in the small angle range for the selection of central or peripheral collisions is confirmed for asymmetric systems. Differential production cross sections of Z = 1 fragments show evidence for the existence of two emitting sources. The apparent temperature of each source is obtained from comparison with a thermodynamical model.

2 data tables

Table 1

THE NUCLEUS IS NAF. CHARGED PARTICLES IN THE CENTRAL DRIFT CHAMBER OF THE DIOGENE DETECTOR.

Table 2

THE NUCLEUS IS NAF. CHARGED PARTICLES IN THE CENTRAL DRIFT CHAMBER OF THE DIOGENE DETECTOR. THE EVENT SELECTION:A HEAVY FRAGMENT(Z>=6) IS REGISTRED IN THE PLASTIC WALL OF THE DIOGENE.

rivet Analysis
A Study of charged particle multiplicities in hadronic decays of the Z0

The OPAL collaboration Acton, P.D. ; Alexander, G. ; Allison, John ; et al.

Z.Phys.C 53 (1992) 539-554, 1992.

Inspire Record 321190 DOI 10.17182/hepdata.14774

We present an analysis of multiplicity distributions of charged particles produced inZ0 hadronic decays. The results are based on the analysis of 82941 events collected within 100 MeV of theZ0 peak energy with the OPAL detector at LEP. The charged particle multiplicity distribution, corrected for initial-state radiation and for detector acceptance and resolution, was found to have a mean 〈nch〉=21.40±0.02(stat.)±0.43(syst.) and a dispersionD=6.49±0.02(stat.)±0.20(syst.). The shape is well described by the Lognormal and Gamma distributions. A negative binomial parameterisation was found to describe the shape of the multiplicity distribution less well. A comparison with results obtained at lower energies confirms the validity of KNO(-G) scaling up to LEP energies. A separate analysis of events with low sphericity, typically associated with two-jet final states, shows the presence of features expected for models based on a stochastic production mechanism for particles. In all cases, the features observed in the data are well described by the Lund parton shower model JETSET.

8 data tables

Table 1

Distribution for whole event. The data at multiplicites 2 and 4 come from Monte Carlo data.

Table 2

Distribution for single hemisphere.

Table 3

Distribution for whole event. The data at multiplicites 2 and 4 come from Monte Carlo data.. Contributions from K0S and LAMBDA decays have been subtracted.

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Characteristics of helium fragments produced in Si-28 emulsion interactions at 14.5-A-GeV

Singh, G. ; Ismail, A.Z.M. ; Jain, P.L. ;

Phys.Rev.C 43 (1991) 2417-2421, 1991.

Inspire Record 323101 DOI 10.17182/hepdata.26112

We report the measurements on partial production cross sections of the multiple helium fragments emitted in the interactions of Si28 ions at 14.5A GeV in nuclear emulsion. Interaction mean free paths of the helium fragments have been investigated on the basis of helium multiplicity and size of the target nucleus as a function of the distance from their production points. Multiplicity scaling in the produced helium fragments is also observed.

5 data tables

Table 1

FIRST REACTION RESPECTS CENTRAL, SECOND - PERIPHERAL INELASTIC INTERACTION.

Table 2

FIRST REACTION RESPECTS CENTRAL, SECOND - PERIPHERAL INTERACTION. THIRD REACTION RESPECT 0HE PRODUCTION.

Table 3

MULT(FRAGT) IS AVERAGED NUMBER OF HEAVY TRACKS FROM THE TARGET NUCLEUS, MULT(SHOWER) IS AVERAGED NUMBER OF MINIMUM IONIZING SHOWER TRACKS WHICH INCLUDED THE NUMBER OF SINGLY CHARGED PROJECTILE PROTON TRACKS.

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Multiplicity Distributions in Pseudorapidity Intervals With $^{32}$S at 200-{GeV}/nucleon and $^{16}$O at 200-{GeV}/nucleon and 60-{GeV}/nucleon

Singh, G. ; Sengupta, K. ; Jain, P.L. ;

Phys.Rev.Lett. 61 (1988) 1073, 1988.

Inspire Record 24235 DOI 10.17182/hepdata.20129

We present results of our systematic studies of charged-shower-particle multiplicities and their dependence on pseudorapidity intervals for nearly central events produced by S32 at 200 GeV/nucleon and O16 at 200 and 60 GeV/nucleon in nuclear emulsion. An increase in the particle density with the increase of particle energy and mass is observed. We find an energy-independent linear relation between the maximum particle density (in a given pseudorapidity interval) and shower-particle multiplicity.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

Multiplicity of Charged Particles in 800-{GeV} $p p$ Interactions

The LEBC-MPS collaboration Ammar, R. ; Aziz, T. ; Banerjee, S. ; et al.

Phys.Lett.B 178 (1986) 124-128, 1986.

Inspire Record 231133 DOI 10.17182/hepdata.6558

Results are reported concerning the charged-particle multiplicity distribution obtained in an exposure of the high-resolution hydrogen bubble chamber LEBC to a beam of 800 GeV protons at the Fermilab MPS. This is the first time that such data have been available at this energy. The distribution of the number n ch of charged particles produced in inelastic interactions obeys KNO-scaling. The average multiplicity is 〈 n ch 〉 = 10.26±0.15. For n ch ⩾8 the data can be well fitted to a negative binomial. The difference between the overall experimental multiplicity distribution and that resulting from the latter fit is in agreement with the contribution expected from diffractive processes.

5 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.