QCD studies and determination of alpha(s) in e+ e- collisions at s**(1/2) = 161-GeV and 172-GeV.

The L3 collaboration Acciarri, M. ; Adriani, O. ; Aguilar-Benitez, M. ; et al.
Phys.Lett.B 404 (1997) 390-402, 1997.
Inspire Record 443563 DOI 10.17182/hepdata.47483

We present a study of the structure of hadronic events recorded by the L3 detector at LEP at the center of mass energies of 161 and 172 GeV. The data sample corresponds to an integrated luminosity of 21.25 pb −1 collected during the high energy runs of 1996. The distributions of event shape variables and the energy dependence of their mean values are well reproduced by QCD models. From a comparison of the data with resummed O ( α s 2 ) QCD calculations, we determine the strong coupling constant at the two energies. Combining this with our earlier measurements we find that the strong coupling constant decreases with increasing energy as expected in QCD.

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Study of inclusive strange-baryon production and search for pentaquarks in two-photon collisions at LEP.

The L3 collaboration Achard, P. ; Adriani, O. ; Aguilar-Benitez, M. ; et al.
Eur.Phys.J.C 49 (2007) 395-410, 2007.
Inspire Record 727262 DOI 10.17182/hepdata.51884

Measurements of inclusive production of the Lambda, Xi- and Xi*(1530) baryons in two-photon collisions with the L3 detector at LEP are presented. The inclusive differential cross sections for Lambda and Xi- are measured as a function of the baryon transverse momentum, pt, and pseudo-rapidity, eta. The mean number of Lambda, Xi- and Xi*(1530) baryons per hadronic two-photon event is determined in the kinematic range 0.4 GeV < pt< 2.5 GeV, |eta| < 1.2. Overall agreement with the theoretical models and Monte Carlo predictions is observed. A search for inclusive production of the pentaquark theta+(1540) in two-photon collisions through the decay theta+ -> proton K0s is also presented. No evidence for production of this state is found.

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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.B 577 (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.

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Studies of hadronic event structure in e+ e- annihilation from 30-GeV to 209-GeV with the L3 detector

The L3 collaboration Achard, P. ; Adriani, O. ; Aguilar-Benitez, M. ; et al.
Phys.Rept. 399 (2004) 71-174, 2004.
Inspire Record 652683 DOI 10.17182/hepdata.54900

In this Report, QCD results obtained from a study of hadronic event structure in high energy e^+e^- interactions with the L3 detector are presented. The operation of the LEP collider at many different collision energies from 91 GeV to 209 GeV offers a unique opportunity to test QCD by measuring the energy dependence of different observables. The main results concern the measurement of the strong coupling constant, \alpha_s, from hadronic event shapes and the study of effects of soft gluon coherence through charged particle multiplicity and momentum distributions.

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Differential distributions for event thrust.


Systematic Measurements of Identified Particle Spectra in pp, d+Au and Au+Au Collisions from STAR

The STAR collaboration Abelev, B.I. ; Aggarwal, M.M. ; Ahammed, Z. ; et al.
Phys.Rev.C 79 (2009) 034909, 2009.
Inspire Record 793126 DOI 10.17182/hepdata.104931

Identified charged particle spectra of $\pi^{\pm}$, $K^{\pm}$, $p$ and $\pbar$ at mid-rapidity ($|y|<0.1$) measured by the $\dedx$ method in the STAR-TPC are reported for $pp$ and d+Au collisions at $\snn = 200$ GeV and for Au+Au collisions at 62.4 GeV, 130 GeV, and 200 GeV. ... [Shortened for arXiv list. Full abstract in manuscript.]

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Uncorrected charged particle multiplicity distribution measured in the TPC in $|\eta| < 0.5$ for Au+Au collisions at 62.4 GeV and 200 GeV. The shaded regions indicate the centrality bins used in the analysis. The 200 GeV data are scaled by a factor 5 for clarity.

Uncorrected charged particle multiplicity distribution measured in the TPC in $|\eta| < 0.5$ for Au+Au collisions at 62.4 GeV and 200 GeV. The shaded regions indicate the centrality bins used in the analysis. The 200 GeV data are scaled by a factor 5 for clarity.

Uncorrected charged particle multiplicity distribution measured in the E-FTPC (Au-direction) within $−3.8 < |\eta| < −2.8$ in d+Au collisions at 200 GeV. The shaded regions indicate the centrality bins used in the analysis.

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Measurement of inclusive production of neutral hadrons from Z decays

The L3 collaboration Acciarri, M. ; Adam, A. ; Adriani, O. ; et al.
Phys.Lett.B 328 (1994) 223-233, 1994.
Inspire Record 374698 DOI 10.17182/hepdata.48189

We present a study of the inclusive production of π 0 , η, K s 0 and Λ based on 929,000 hadronic Z decays recorded with the L3 detector at LEP. The measured inclusive momentum distributions have been compared with predictions from parton shower models as well as an analytical Quantum Chromodynamics calculation. Comparing to low energy e + e - data, we find that QCD describes the energy evolution of the hadron spectrum.

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Neutral strange particle production in sulphur sulphur and proton sulphur collisions at 200-GeV/nucleon

The NA35 collaboration Bartke, J. ; Bialkowska, H. ; Bock, R. ; et al.
Z.Phys.C 48 (1990) 191-200, 1990.
Inspire Record 304994 DOI 10.17182/hepdata.15177

The production of Λ,\(\bar \Lambda\) andKs0 has been studied in 200 GeV/nucleonp+S and S+S collisions in the streamer chamber of the NA35 experiment at the CERN SPS. Significant enhancement of the multiplicities of all observed strange particles relative to negative hadrons was observed in central S+S collisions, as compared top+p andp+S collisions. The latter collisions show no overall (relative) strangeness enhancement overp+p, but the rapidity distributions and hadron multiplicities indicate some secondary cascading production of Λ particles in thep+S andp+Au collisions. The Λ polarization in central S+S collisions was found to be compatible with zero up topT=2 GeV/c.

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Tranverse kinetic energy spectra of neutral strange particles in P SU collisions.

Tranverse kinetic energy spectra of neutral strange particles in P SU collisions.

Tranverse kinetic energy spectra of neutral strange particles in SU SU collisions.

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Excitation of the Delta (1232) resonance in proton - nucleus collisions

Trzaska, M. ; Pelte, D. ; Lemaire, M. -C. ; et al.
Z.Phys.A 340 (1991) 325-331, 1991.
Inspire Record 314551 DOI 10.17182/hepdata.15689

The excitation of theΔ resonance is observed in proton collisions on C, Nb and Pb targets at 0.8 and 1.6 GeV incident energies. The mass E0 and widthΓ of the resonance are determined from the invariant mass spectra of correlated (p, π±)-pairs in the final state of the collision: The mass E0 is smaller than that of the free resonance, however by comparing to intra-nuclear cascade calculations, this reduction is traced back to the effects of Fermi motion, NN scattering and pion reabsorption in nuclear matter.

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Recent results from experiment NA35.

The NA35 collaboration Seyboth, P. ; Baechler, J. ; Bartke, J. ; et al.
Nucl.Phys.A 544 (1992) 293C-307C, 1992.
Inspire Record 343637 DOI 10.17182/hepdata.36668

Enhanced strange particle production, nonstatistical multiplicity fluctuations and two-pion Bose-Einstein correlations were measured in O, S-nucleus reactions at 60 and 200 GeV/nucleon. The results indicate significant collective effects in high-energy nucleus-nucleus collisions.

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CENTRAL COLLISIONS.

CENTRAL COLLISIONS.


Pion and kaon production in central Pb+Pb collisions at 20A and 30A GeV: Evidence for the onset of deconfinement

The NA49 collaboration Alt, C. ; Anticic, T. ; Baatar, B. ; et al.
Phys.Rev.C 77 (2008) 024903, 2008.
Inspire Record 762554 DOI 10.17182/hepdata.25169

Results on charged pion and kaon production in central Pb+Pb collisions at 20A and 30A GeV are presented and compared to data at lower and higher energies. A rapid change of the energy dependence is observed around 30A GeV for the yields of pions and kaons as well as for the shape of the transverse mass spectra. The change is compatible with the prediction that the threshold for production of a state of deconfined matter at the early stage of the collisions is located at low SPS energies.

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Transverse mass spectra for pion production in the central rapidity region for collisions at 20 GeV per nucleon.

Transverse mass spectra for pion production in the central rapidity region for collisions at 30 GeV per nucleon.

Transverse mass spectra for kaon production in the central rapidity region for collisions at 20 GeV per nucleon.

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