HEPData Search

We have performed a high statistics measurement of the production rate and the energy flow pattern of hadron events between √ s =33 and 36.7 GeV. The data show no evidence for the production of a new quark with charge 2 3 e . Planar events in e + e − →hadrons are shown to have three well separated jets. The production rate and the shape of three-jet events are compared with many models and we find that only the QCD model can explain the data.

1 data table

Table 1

ENERGY SCAN WITH 7077 HADRON EVENTS.

Charged Particle Multiplicities in ($p p$) Interactions and Comparison With ($e^+ e^-$) Data

Basile, M. ; Cara Romeo, G. ; Cifarelli, L. ; et al.

Nuovo Cim.A 65 (1981) 400, 1981.

Inspire Record 166765 DOI 10.17182/hepdata.37470

By using three different c.m. energies in pp interactions,$\sqrt s $, 44, 62 GeV, it is shown that the average charged-particle multiplicity <nch> sclaes with$\sqrt s $ once the correct hadronic energy available for multiparticle production,Ehad, is used as basic parameter. The pp data, analysed in this way, are compared with e+e− data at equivalent energies. The agreement is very satisfactory.

6 data tables

Table 1

WITH SQRT(S) OF 30 GEV.

Table 2

WITH SQRT(S) OF 44 GEV.

Table 3

WITH SQRT(S) OF 62 GEV.

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Forward and Backward Multiplicities in $K^- p$ Interactions at 110-{GeV}/$c$

The Aachen-Berlin-CERN-Cracow-London-Vienna-Warsaw collaboration Gottgens, R. ; Kohli, J.M. ; Sixel, P. ; et al.

Z.Phys.C 11 (1981) 189, 1981.

Inspire Record 166387 DOI 10.17182/hepdata.16482

Multiplicity distributions and correlations between charged particles in the forward and back-ward c.m. hemispheres are studied inK−p interactions at 110 GeV/c and compared with other data on mesonnucleon scattering. The interpretation in terms of a simple quark-parton picture assuming that the forward multiplicity is dominated by quark fragmentation and the backward multiplicity by diquark fragmentation is supported by the experimental fact that the forward and the backward mean multiplicities are approximately equal to half of thee+e− andpp multiplicities, respectively. The 110 GeV/cK−p data show significant correlations between the numbers of slow forward and slow backward particles, whereas the multiplicities of fast forward and fast backward particles are independent.

2 data tables

Table 1

CHARGED MULTIPLICITY PER INELASTIC EVENT.

Table 2

NONDIFFRACTIVE SAMPLE ( -0.85 < XL < 0.85 ). CHARGED MULTIPLICITY PER INELASTIC EVENT.

Inclusive $\Lambda$ and $\bar{\Lambda}$ Production in $K^+ p$ Interactions at 70-{GeV}/$c$

The Brussels-CERN-Genoa-Mons-Nijmegen-Serpukhov collaboration Barth, M. ; De Clercq, C. ; De Wolf, E.A. ; et al.

Z.Phys.C 10 (1981) 205, 1981.

Inspire Record 166163 DOI 10.17182/hepdata.2217

Inclusive and semi-inclusive production of Λ and$\bar \Lambda$ inK+p interactions is studied at an incident momentum of 70 GeV/c. Cross sections and single particle distributions are presented and compared with data at lower energies. Scaling is observed between 32 and 70 GeV/c in the Feynmanx variable in the target and the beam fragmentation regions for Λ and$\bar \Lambda$ inclusive production respectively. An increase of Λ ($\bar \Lambda$) production is observed in the beam (target) fragmentation regions, whereas the data at 70 and 32 GeV/c are reasonably close in the central region. The dependence of the Λ($\bar \Lambda$) polarization as a function ofx is measured and found to be in general agreement with the results at 32 GeV/c. The (Λ$\bar \Lambda$) pair production cross section increases significantly from 32 to 70 GeV/c. The Λ and$\bar \Lambda$ production associated with an identified proton is also studied.

4 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Inclusive Neutral Strange Particle Production in Neutrino $p$ Interactions

The Aachen-Bonn-CERN-Munich-Oxford collaboration Grassler, H. ; Lanske, D. ; Schulte, R. ; et al.

Nucl.Phys.B 194 (1982) 1-20, 1982.

Inspire Record 166157 DOI 10.17182/hepdata.34244

In a selected sample of 6770 charged current (CC) events of νp interactions with 〈 E ν 〉 = 43 GeV and 〈W〉 = 4.6 GeV , 359 K 0 , 180 Λ and 13 Λ have been observed, which corresponds to a corrected production rate at least one neutral strange particle in (17.4±0.8)% of the CC events. The ratio of the inclusive Λ to K 0 production cross section is found to be 0.26±0.03. The number of CC events containing at least one K 0 increases with increasing E ν and Q 2 , while the CC events containing at least one Λ remain practically constant. The fractions of the total hadronic energy carried by K 0 and Λ are found to be approximately the same in νp as in ep and μp interactions. In the hadronic c.m.s., the K 0 are produced mostly forwards, the Λ mostly backwards, with asymmetry parameters of +0.32±0.02 and −0.45±0.06, respectively. The total strange particle production cross section is estimated to be (25±4)% of the cross section for production of CC events with W >1.5 GeV and that for charm production (10±2)% of the CC cross section well above charm threshold ( W >3 GeV). The production of the resonances K ∗+ (890) and Σ + (1385) has been observed. The production rate of K ∗+ (890) is comparable to that of D ∗+ (2009), above the corresponding thresholds.

1 data table

Table 1

No description provided.

Study of Longitudinal Distributions in the Fragmentation Regions, Using the Quark - Parton Model in $K^- p$ Interactions at 70-{GeV}/$c$

de Billy, L. ; Briand, H. ; Dumarchez, J. ; et al.

Nucl.Phys.B 191 (1981) 574-590, 1981.

Inspire Record 10816 DOI 10.17182/hepdata.34218

The study of π ± , π 0 , K 0 and Λ production in the fragmentation regions (| x |0.2) of K − p interactions at 70 GeV/ c shows that the x -dependence of each invariant cross section is well described by the power law (1−| x |) n suggested by the dimensional counting rule. Furthermore, pion production is found, both in K − and proton fragmentation regions, to be very similar to their production in ν( ν ) p interactions as expected from quark-parton models. The quark and diquark fragmentation functions D u π , D uu π and D ud π are extracted from our data.

1 data table

Table 1

No description provided.

A-dependence of Muon Pair Production in $\pi^-$ Nucleus Interactions at 280-{GeV}/$c$

Falciano, S. ; Freudenreich, K. ; Juillot, P. ; et al.

Phys.Lett.B 104 (1981) 416-420, 1981.

Inspire Record 166161 DOI 10.17182/hepdata.31061

We have measured the relative cross sections for muon pair production by 280 GeV/ c negative pions on three different targets: carbon, copper, and tungsten. The value of α obtained from the parametrization σ = constant × A α is 0.94 ± 0.02 ± 0.02, whereas the parametrization σ≈σ 0 ( Z A ) A α′ , where σ 0 ( Z A ) is given by the Drell-Yan model, leads to α ′ = 0.97 ±0.02±0.02. This last result is in agreement with the quark additivity rule which is inherent in the Drell-Yan model, no dependence is observed on the transverse momentum of the muon pair.

2 data tables

Table 1

PARAMETRISATION OF CROSS-SECTION IS SIG=CONST.*A**POWER.

Table 2

PARAMETRISATION OF CROSS-SECTION IS SIG=SIG0(Z/A)*A**POWER WHERE SIG0(Z/A) IS GIVEN BY DRELL-YAN MODEL.

rivet Analysis
Baryon Production in e+ e- Annihilation at PETRA

The JADE collaboration Bartel, W. ; Cords, D. ; Dittmann, P. ; et al.

Phys.Lett.B 104 (1981) 325-329, 1981.

Inspire Record 166363 DOI 10.17182/hepdata.31062

Data on p and Λ production by e + e − -annihilation at CM energies between 30 and 36 GeV are presented. Indication for an angular anticorrelation in events with baryon-antibaryon pairs is seen.

3 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

AVERAGE NUMBER OF ANTIBARYONS PER HADRONIC EVENT. AN EXPONENTIAL SLOPE OF 2.5 GEV*-1 IN E WAS ASSUMED IN EXTRAPOLATING E*D3(SIG)/DP**3 TO ALL MOMENTA.

Forward Produced Protons and Anti-protons in Deep Inelastic Muon Proton Scattering

The European Muon collaboration Aubert, J.J. ; Bassompierre, G. ; Becks, K.H. ; et al.

Phys.Lett.B 103 (1981) 388, 1981.

Inspire Record 166178 DOI 10.17182/hepdata.31185

A significant rate of forward proton and antiproton production has been observed in 120 and 280 GeV muon-proton scattering. The z and p T 2 distributions are presented. The dependence of the normalized production cross section on the muon variables x and Q 2 is studied.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

Date

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CM Energies (GeV)

Authors Reset

OBSERVATION OF pi- MESON CORRELATED EMISSION IN C - Ta INTERACTIONS AT P (0) = 4.2-GEV/c PER NUCLEON

rivet Analysis
Measurement of Hadron Production and Three Jet Event Properties at {PETRA} {MIT}

Charged Particle Multiplicities in ($p p$) Interactions and Comparison With ($e^+ e^-$) Data

Forward and Backward Multiplicities in $K^- p$ Interactions at 110-{GeV}/$c$

Inclusive $\Lambda$ and $\bar{\Lambda}$ Production in $K^+ p$ Interactions at 70-{GeV}/$c$

Inclusive Neutral Strange Particle Production in Neutrino $p$ Interactions

Study of Longitudinal Distributions in the Fragmentation Regions, Using the Quark - Parton Model in $K^- p$ Interactions at 70-{GeV}/$c$

A-dependence of Muon Pair Production in $\pi^-$ Nucleus Interactions at 280-{GeV}/$c$

rivet Analysis
Baryon Production in e+ e- Annihilation at PETRA

Forward Produced Protons and Anti-protons in Deep Inelastic Muon Proton Scattering