Ansari, R.
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rivet Analysis
First Observation of $\gamma \gamma \to K^*+ K^*$-

The ARGUS collaboration Albrecht, H. ; Bockmann, P. ; Glaser, R. ; et al.
Phys.Lett.B 212 (1988) 528-532, 1988.
Inspire Record 262713 DOI 10.17182/hepdata.29893

The final states K S 0 K S 0 π + π − and K S 0 K ∓ π 0 π ± , produced in two-photon reactions, have been studied using the ARGUS detector at the e + e − storage ring DORIS II at DESY. The reaction γγ→ K ∗+ K ∗− has been observed for the first time. Its cross section is about eight times larger than that for γγ→ K ∗0 K ∗0 , but it has a similar W γγ dependence.

4 data tables
Table 1

No description provided.

Table 2

Topological cross section.

Table 3

Topological cross section.

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THE DEPENDENCE OF CHARACTERISTICS OF pi+- MESONS PRODUCED IN pi- C INTERACTIONS AT 40-GeV/c ON TOTAL ENERGY IN THE CMS AND QCD OF SEMIHARD PROCESS

Baatar, Ts. ; Ivanovskaya, I.A. ; Serdamba, L. ; et al.
JINR-P1-88-469, 1988.
Inspire Record 267040 DOI 10.17182/hepdata.38869

None

3 data tables
Table 1

THE MULTIPLICITY OF CHARGED PIONS HAS BEEN FITTED BY THE FORMULA: MULT(PI+-)=CONST(Q=1)+CONST(Q=2)*EXP(+SLOPE*2*SQRT(LN(S))), WHERE S IS THE TOTAL ENERGY SQUERED OF THE SYSTEM PROJECTILE - PARTICIPATOR AND IS DEFINED AS 2*E(P=1)*(TARGET MASS), WHERE TARGET MASS HAS BEEN OBTAINED AS A SUM OF (E-PL) OVER SECONDARY PARTICLES.

Table 2

THE AVERAGE PT OF CHARGED PIONS HAS BEEN FITTED BY THE FORMULA: MEAN(N=PT)=CONST(Q=1)+CONST(Q=2)*EXP(SLOPE*SQRT(LN(S))), WHERE S IS THE TOTAL ENERGY SQUERED OF THE SYSTEM PROJECTILE - PARTICIPATOR AND IS DEFINED AS 2*E(P=1)*(TARGET MASS), WHERE TARGET MASS HAS BEEN OBTAINED AS A SUM OF (E-PL) OVER SECONDARY PARTICLES.

Table 3

THE AVERAGE PT**2 OF CHARGED PIONS HAS BEEN FITTED BY THE FORMULA: MEAN(N=PT**2)=CONST(Q=1)+CONST(Q=2)*EXP(SLOPE*SQRT(LN(S))), WHERE S IS THE TOTAL ENERGY SQUERED OF THE SYSTEM PROJECTILE - PARTICIPATOR AND IS DEFINED AS 2*E(P=1)*(TARGET MASS), WHERE TARGET MASS HAS BEEN OBTAINED AS A SUM OF (E-PL) OVER SECONDARY PARTICLES.


rivet Analysis
Inclusive $\phi$ Meson Production in Electron - Positron Interactions in the Energy Region of the $\Upsilon$ Resonances

The ARGUS collaboration Albrecht, H. ; Bockmann, P. ; Glaser, R. ; et al.
Z.Phys.C 41 (1989) 557, 1989.
Inspire Record 262551 DOI 10.17182/hepdata.15528

We report on a high precision measurement of ϕ-meson production in continuum events and in direct decays of the Υ(1S)- and Υ(2S)-mesons. The ratio of the total production rate of ϕ-mesons in direct Υ(1S)- and Υ(2S)-decays over that in continuum events is 1.32±0.08±0.09 and 1.07±0.13±0.11 respectively. This is compatible with the corresponding ratio obtained for lighter mesons, but is appreciably smaller than the relative baryon production rate.

6 data tables
Table 1

PHI meson cross section on the continuum.

Table 2

Differential particle density for PHI mesons in decays of upsilon(1S) and upsilon(2S).

Table 3

No description provided.

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rivet Analysis
Charged Particle Production in $K^+ p$, $\pi^+ p$ and $p p$ Interactions at 250-{GeV}/$c$

The EHS/NA22 collaboration Adamus, M. ; Azhinenko, I.V. ; Ataian, M.R. ; et al.
Z.Phys.C 39 (1988) 311-329, 1988.
Inspire Record 265504 DOI 10.17182/hepdata.15620

None

6 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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rivet Analysis
Charged Particle Correlations in $\bar{P} P$ Collisions at c.m. Energies of 200-{GeV}, 546-{GeV} and 900-{GeV}

The UA5 collaboration Ansorge, R.E. ; Åsman, B. ; Booth, C.N. ; et al.
Z.Phys.C 37 (1988) 191-213, 1988.
Inspire Record 263399 DOI 10.17182/hepdata.15683

We present data on two-particle pseudorapidity and multiplicity correlations of charged particles for non single-diffractive\(p\bar p - collisions\) at c.m. energies of 200, 546 and 900 GeV. Pseudorapidity correlations interpreted in terms of a cluster model, which has been motivated by this and other experiments, require on average about two charged particles per cluster. The decay width of the clusters in pseudorapidity is approximately independent of multiplicity and of c.m. energy. The investigations of correlations in terms of pseudorapidity gaps confirm the picture of cluster production. The strength of forward-backward multiplicity correlations increases linearly with ins and depends strongly on position and size of the pseudorapidity gap separating the forward and backward interval. All our correlation studies can be understood in terms of a cluster model in which clusters contain on average about two charged particles, i.e. are of similar magnitude to earlier estimates from the ISR.

3 data tables
Table 1

Correlation strength for different choices of pseudorapidity intervals.

Table 2

Correlation strength as a function of the central gap size for the symmetric data.

Table 3

Correlation strength as a function of the centre of the separating gap for a gap size of 2.


Comparative Properties of 400-{GeV}/$c$ Proton - Proton Interactions With and Without Charm Production

The LEBC-EHS collaboration Aguilar-Benitez, M. ; Allison, W.W. M. ; Bailly, J.L. ; et al.
Z.Phys.C 41 (1988) 191, 1988.
Inspire Record 263783 DOI 10.17182/hepdata.57563

A comparative analysis of the global properties of 400 GeV/c proton-proton interactions with and without charm production is presented. Multiplicities, momentum distributions, sphericity and thrust of these interactions are compared.

2 data tables
Table 1

Charged particle multiplicity distributions for 400 GeV/c proton-proton interactions without charmproduction. The data shown are corrected for trigger losses. No information on cuts and systematic errors, data extracted with g3data.

Table 2

Charged particle multiplicity distributions for 400 GeV/c proton-proton interactions with charmproduction. The data shown are corrected for trigger losses. No information on cuts and systematic errors, data extracted with g3data.


rivet Analysis
Measurement of the Reaction $e^+ e^- \to \eta \pi^+ \pi^-$ in the Center-of-mass Energy Interval 1350-{MeV} to 2400-{MeV}

The DM2 collaboration Antonelli, A. ; Baldini, R. ; Calcaterra, A. ; et al.
Phys.Lett.B 212 (1988) 133-138, 1988.
Inspire Record 264144 DOI 10.17182/hepdata.29912

The e + e − → ηπ + π − reaction has been measured in the center of mass energy interval 1350–2400 MeV by the magnetic detector DM2 at the Orsay storage ring DCI. Under the hypothesis of only one large resonance the cross section is not fit in a satisfactory way. The branching ratio τ − → η − π 0 ν τ =(0.13 ± 0.02)% is deduced via CVC from the above measurement.

1 data table
Table 1

No description provided.


rivet Analysis
Observation of the Charmed Baryon $\Sigma(c$) in $e^+ e^-$ Annihilations

The ARGUS collaboration Albrecht, H. ; Bockmann, P. ; Glaser, R. ; et al.
Phys.Lett.B 211 (1988) 489-492, 1988.
Inspire Record 261672 DOI 10.17182/hepdata.29913

Using the ARGUS detector at the DORIS II storage ring, we have observed the charmed baryons Σ c ++ and Σ c 0 , through their decays to Λ c + π ± . We have measured the mean Σ c −Λ c + mass difference as 167.6±0.3±1.6 MeV/ c 2 . The isospin mass splitting between the Σ c ++ and the Σ c 0 was found to be 1.2±0.7±0.3 MeV/ c 2 . The rate of Λ c + production from Σ c decays was found to be (36±12±11)% of the total rate of Λ c + production. The Σ c χ p spectrum was observed to be similar to that of the Λ c + , with a Peterson function parameter ϵ of 0.29±0.06.

1 data table
Table 1

DATA FROM UPSI(4S) WAS EXCLUDED.


Shadowing in deep inelastic muon scattering from nuclear targets

The European Muon collaboration Arneodo, M. ; Arvidson, A. ; Aubert, J.J. ; et al.
Phys.Lett.B 211 (1988) 493-499, 1988.
Inspire Record 262246 DOI 10.17182/hepdata.29908

Results are presented on the ratio of the inelastic muon-nucleus cross section per nucleon for carbon and calcium relative to that for deuterium. The measurements were made in the kinematic range of low x (0.003–0.1) and low Q 2 (0.3–3.2 GeV 2 ) at an incident muon energy of 280 GeV. The calcium to deuterium ratio shows a significant x dependence which is interpreted as a shadowing effect. No strong Q 2 dependence is observed. This suggests that the effect is due at least partially to parton interactions within the nucleus.

4 data tables
Table 1

VALUES OF Q**2 AT EACH POINT ARE:- 0.52,0.60,0.61,0.61,0.63,0.68,0.90.

Table 2

VALUES OF Q**2 AT EACH POINT ARE:- 1.09,1.25,1.54,1.74,1.76,1.68,1.71, 2.29.

Table 3

VALUES OF X AT EACH POINT ARE:- 0.009,0.011,0.010,0.010,0.010,0.011, 0.013,0.015.

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EXPERIMENTAL MASS LIMIT FOR A FOURTH GENERATION SEQUENTIAL LEPTON FROM e+ e- ANNIHILATIONS AT S**(1/2) = 56-GeV

The AMY collaboration Kim, G.N. ; Kim, E.J. ; Son, D. ; et al.
Phys.Rev.Lett. 61 (1988) 911, 1988.
Inspire Record 261848 DOI 10.17182/hepdata.20055

A search for pair production of fourth-generation sequential leptons in e+e− annihilation at a center-of-mass energy s=56 GeV is reported. Event topologies corresponding to the cases where one particle decays leptonically while the other decays hadronically as well as those where both particles decay hadronically were explored. We set a 95%-confidence-level lower limit of 27.6 GeV/c2 for the mass of a fourth-generation lepton.

1 data table
Table 1

No description provided.