HEPData Search

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Transverse-energy distributions at midrapidity in $p$$+$$p$, $d$$+$Au, and Au$+$Au collisions at $\sqrt{s_{_{NN}}}=62.4$--200~GeV and implications for particle-production models

The PHENIX collaboration Adler, S.S. ; Afanasiev, S. ; Aidala, C. ; et al.

Phys.Rev.C 89 (2014) 044905, 2014.

Inspire Record 1273625 DOI 10.17182/hepdata.63512

Measurements of the midrapidity transverse energy distribution, $d\Et/d\eta$, are presented for $p$$+$$p$, $d$$+$Au, and Au$+$Au collisions at $\sqrt{s_{_{NN}}}=200$ GeV and additionally for Au$+$Au collisions at $\sqrt{s_{_{NN}}}=62.4$ and 130 GeV. The $d\Et/d\eta$ distributions are first compared with the number of nucleon participants $N_{\rm part}$, number of binary collisions $N_{\rm coll}$, and number of constituent-quark participants $N_{qp}$ calculated from a Glauber model based on the nuclear geometry. For Au$+$Au, $\mean{d\Et/d\eta}/N_{\rm part}$ increases with $N_{\rm part}$, while $\mean{d\Et/d\eta}/N_{qp}$ is approximately constant for all three energies. This indicates that the two component ansatz, $dE_{T}/d\eta \propto (1-x) N_{\rm part}/2 + x N_{\rm coll}$, which has been used to represent $E_T$ distributions, is simply a proxy for $N_{qp}$, and that the $N_{\rm coll}$ term does not represent a hard-scattering component in $E_T$ distributions. The $dE_{T}/d\eta$ distributions of Au$+$Au and $d$$+$Au are then calculated from the measured $p$$+$$p$ $E_T$ distribution using two models that both reproduce the Au$+$Au data. However, while the number-of-constituent-quark-participant model agrees well with the $d$$+$Au data, the additive-quark model does not.

42 data tables match query

Table 1

Et EMC distributions for sqrt(sNN) = 62.4 GeV Au+Au collisions shown in 5% wide centrality bins.

Table 3

Et EMC distributions for sqrt(sNN) = 62.4 GeV Au+Au collisions shown in 5% wide centrality bins.

Table 4

Et EMC distributions for sqrt(sNN) = 62.4 GeV Au+Au collisions shown in 5% wide centrality bins.

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Study of Inclusive Production of Boson Resonances in $\bar{p} p$ Interactions at 32-{GeV}/$c$

The French-Soviet & CERN-Soviet collaborations Starchenko, E.A. ; Chekulaev, S.V. ; Galyaev, N.A. ; et al.

Z.Phys.C 16 (1983) 181, 1983.

Inspire Record 168177 DOI 10.17182/hepdata.22268

The inclusive production ofK*±(890), ρρ(770), ω0(780) andf0(1,270) mesons is studied in$\bar pp$ experiment at 32GeV/c in the MIRABELLE bubble chamber by the analysis of (K0π±) and (π+π−) invariant mass distributions. The inclusive cross sections are σ(K*±)=2.45±0.30 mb, σ(ρ0)=8.8 ±0.9 mb, σ(ω+)≃6.2 mb, and σ(f0)=2.2±0.7 mb. The C.M. longitudinal distribution of theK*±(890) is slightly shifted to the primary particles fragmentation regions; the ρ0 is produced more centrally. The studied mesons alone are responsible for 40% of final state poins. The production features of various resonances are compared with quark models predictions.

13 data tables match query

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Properties of Hadronic Events in e$^{+} $e$^{-}$ Annihilation at $S^{(1/2)}=91$-{GeV}

The ALEPH collaboration Decamp, D. ; Deschizeaux, B. ; Lees, J.P. ; et al.

Phys.Lett.B 234 (1990) 209-218, 1990.

Inspire Record 283354 DOI 10.17182/hepdata.29739

We report on properties of hadronic events from e + e − annihilation observed by the ALEPH detector at the large Electron Positron Collider at CERN. The center-of-mass energy was s =91.0−91.3 GeV . Measured distributions of the global event-shape variables sphericity, aplanarity, thrust and minor value, and of the inclusive variables x p , p ⊥ in , p ⊥ out and y are presented. We measure a mean charged multiplicity in hadronic events of 〈 N ch 〉=21.3±0.1 (statistical)±0.6 (systematic). The data are in good agreement with QCD-based models which use the leading-logarithm approximation, and are less well described by a model using O( α s 2 ) QCD.

1 data table match query

Table 1

NO RAD. CORR APPLIED.

Scaling Violation Favoring High Multiplicity Events at 540-GeV CMS Energy

The UA5 collaboration Alner, G.J. ; Alpgard, K. ; Ansorge, R.E. ; et al.

Phys.Lett.B 138 (1984) 304-310, 1984.

Inspire Record 199419 DOI 10.17182/hepdata.30571

New data are presented on the charged multiplicity distribution for non single-diffractive events produced in pp̄ interactions at a CM energy s = 540 GeV . The distribution in the full pseudorapidity range is compared with data from the ISR. Using the scaling variable z = n 〈n〉 a change of shape is observed. The effect is manifested as an increase from 2% to 6% in the proportion of high multiplicity ( z > 2) events. For the central pseudorapidity range, | η | ⪅ 1.5, scaling is approximately valid up to s = 540 GeV .

1 data table match query

Table 4

MOMENTS OF THE CHARGED MULTIPLICITY DISTRIBUTIONS. DISPERSION IS MEAN(N-MEAN(N)**2). CQ IS MEAN(N**Q)/MEAN(N)**Q.

Vector and Tensor Meson Production in $K^- p$ Interactions at 32-{GeV}/$c$

The French-Soviet & CERN-Soviet collaborations Cochet, C. ; Lewin, C. ; Barloutaud, R. ; et al.

Nucl.Phys.B 155 (1979) 333-356, 1979.

Inspire Record 141994 DOI 10.17182/hepdata.34666

Inclusive production of vector and tensor mesons is studied in a K − p experiment at 32 GeV/ c in the MIRABELLE bubble chamber. The K ∗ 0 (890) , ϱ 0 and ω cross sections are comparable, about 4 mb each. The K ∗ 0 (1420 and cross sections are also comparable, about 1 mb each. The K ∗ o ̈ + (890), Φ, K ∗ o ̈ − (1420) and f cross sections beam fragmentation; ϱ production is almost forward-backward symmetric in the c.m.s. The p T production slopes of K ∗ o ̈ − (890) and ϱ are similar, the Φ slope is shallower. Vector and tensor mesons alone are responsible for ≅50% (≅60%) of final-state pions

1 data table match query

Table 1

No description provided.

Particle Multiplicities in K- p Interactions at 32-GeV/c

The French-Soviet & CERN-Soviet collaborations Cochet, C. ; Barloutaud, R. ; Berard, A. ; et al.

Nucl.Phys.B 124 (1977) 61-80, 1977.

Inspire Record 118795 DOI 10.17182/hepdata.35364

The inclusive cross section and the average multiplicity are evaluated for most of the charged ( π ± , p, K ± ) and neutral (γ, π 0 , K 0 , K 0 , Λ, Λ , n ) particles produced in 32 GeV/ c K − p interactions; corresponding results are obtained for each charged topology separately. New results are given for the total charged multiplicity cross sections. The average longitudinal momentum of neutrals is found to be roughly equal to that of charged particles. The π + and π − multiplicity distributions are reconstructed and compared to the π 0 and to the total charged multiplicity distributions.

6 data tables match query

Table 1

No description provided.

Table 2

Axis error includes +- 30/30 contribution (SYSTEMATIC ERROR FOR K0 MULTIPLICITY, WHICH IS EVALUATED FROM 2 ASSUMPTIONS: ALL K0'S COME FROM THE FINAL STATES (N K 2AK PIONS) OR (LAMBDA/SIGMA K AK PIONS) AND CHARGE DISTRIBUTION IN THESE FINAL STATES OBEYS A STATISTICAL ISOSPIN MODEL OF F.CERULUS,NC 19, 528. ALSO ASSUMED THAT SIG(K+)=SIG(KO). VALUES OF SIG(XI-) AND RATIOS SIG(SIGMA+)/SIG(LAMBDA), SIG(SIGMA-)/SIG(LAMBDA) ARE TAKEN FROM 14.3 GEV EXPERIMENT LOUEDEC 76,NC 41A, 166, STATISTICAL ERRORS BEING DOUBLED. FOR ALL ANTIBARYONS ASSUMED THAT SIG(ANTIBARYON)/SIG(BARYON)=SIG(ANTILAMBDA)/SIG(LAMBDA) =0.046+-0.020. SLOW PROTONS WITH PLAB < 1.2 GEV/C ARE IDENTIFIED, AN ESTIMATE FOR FAST PROTON PRODUCTION IS TAKEN FROM FACCINI 77,NP B127, 109).

Table 3

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Measurement of charged particle multiplicities in $pp$ collisions at ${\sqrt{s} =7}$TeV in the forward region

The LHCb collaboration Aaij, R. ; Abellan Beteta, C. ; Adeva, B. ; et al.

Eur.Phys.J.C 72 (2012) 1947, 2012.

Inspire Record 1082369 DOI 10.17182/hepdata.65435

The charged particle production in proton-proton collisions is studied with the LHCb detector at a centre-of-mass energy of ${\sqrt{s} =7}$TeV in different intervals of pseudorapidity $\eta$. The charged particles are reconstructed close to the interaction region in the vertex detector, which provides high reconstruction efficiency in the $\eta$ ranges $-2.5<\eta<-2.0$ and $2.0<\eta<4.5$. The data were taken with a minimum bias trigger, only requiring one or more reconstructed tracks in the vertex detector. By selecting an event sample with at least one track with a transverse momentum greater than 1 GeV/c a hard QCD subsample is investigated. Several event generators are compared with the data; none are able to describe fully the multiplicity distributions or the charged particle density distribution as a function of $\eta$. In general, the models underestimate the charged particle production.

8 data tables match query

Table 1

Charged particle multiplicity distribution in minimum bias events for different pseudorapidity bins. The first quoted uncertainty is statistical and the second is systematic.

Table 2

Charged particle multiplicity distribution in hard QCD events for different pseudorapidity bins. The first quoted uncertainty is statistical and the second is systematic.

Table 3

Charged particle multiplicity distribution for minimum bias events in the full pseudorapidity range. The first quoted uncertainty is statistical and the second is systematic.