Date

NUCLEUS IS NUCLEAR PHOTOEMULSION. EVENT WITH A TOTAL CHARGE OF ALL SPECTATOR FRAGMENTS OF A PROJECTILE = 0.

NUCLEUS IS NUCLEAR PHOTOEMULSION. EVENT WITH A TOTAL CHARGET OF ALL SPECTATOR FRAGMENTS OF A PROJECTILE = 1.

NUCLEUS IS NUCLEAR PHOTOEMULSION.

More…

Studies of Jet Production Rates in $e^+ e^-$ Annihilation at $e$({CM}) = 29-{GeV}

Bethke, S. ; Abrams, G. ; Adolphsen, C.E. ; et al.
Z.Phys.C 43 (1989) 325, 1989.
Inspire Record 277772 DOI 10.17182/hepdata.15472

Production rates of multijet hadronic final states are studied ine+e− annihilation at 29 GeV center of mass energy. QCD shower model calculations with exact first order matrix element weighting at the first gluon vertex are capable of reproducing the observed multijet event rates over a large range of jet pair masses. The method used to reconstruct jets is well suited for directly comparing experimental jet rates with parton rates calculated in perturbative QCD. Evidence for the energy dependene of αs is obtained by comparing the observed production rates of 3-jet events with results of similar studies performed at higher center of mass energies.

2 data tables

Observed production rates relative to the total hadronic cross section.

Production rates corrected for fragmentation, initial state radiation and detector effects.


Charged Particle Multiplicity Distributions at 200-GeV and 900-GeV Center-Of-Mass Energy

The UA5 collaboration Ansorge, R.E. ; Åsman, B. ; Burow, L. ; et al.
Z.Phys.C 43 (1989) 357, 1989.
Inspire Record 267179 DOI 10.17182/hepdata.15457

Multiplicity distributions of charged particles produced in non single-diffractive collisions between protons and antiprotons at centre of mass energies of 200 and 900 GeV are presented. The data were recorded in the UA5 streamer chambers at the CERN Collider, which was operated in a pulsed mode between the two energies. A new method to correct for acceptance limitations and inefficiencies based on the principle of maximum entropy has been used. Multiplicity distributions in full phase space and in intervals of pseudorapidity are presented in tabular form. The violation of KNO scaling in full phase space found by the UA5 group at an energy of 546 GeV is confirmed also at 200 and 900 GeV. The shape of the 900 GeV distribution in full phase space is narrower in the peak region than at 200 GeV but exhibits a pronounced high multiplicity tail. The negative binomial distribution fits data at 200 GeV in all pseudorapidity intervals and in small intervals at 900 GeV. In large intervals at 900 GeV, however, the negative binomial distribution. Fits to the partially coherent laser distribution are also presented as well as comparisons with predictions of the Dual Parton, the Fritiof and the Pythia models.

12 data tables

No description provided.

No description provided.

No description provided.

More…

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

Correlation strength for different choices of pseudorapidity intervals.

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

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


Kaon Production at 200-{GeV} and 900-{GeV} Center-of-mass Energy

The UA5 collaboration Ansorge, R.E. ; Asman, B. ; Booth, C.N. ; et al.
Phys.Lett.B 199 (1987) 311-316, 1987.
Inspire Record 254608 DOI 10.17182/hepdata.30057

Results on inclusive kaon production at 200 and 900 GeV centre of mass (CM) energy obtained with the UA5 detector at the pulsed CERN SPS antiproton-proton Collider are presented and compared with our earlier data at 546 GeV. The average transverse momentum 〈 p t 〉 of kaons has been estimated to be (0.50±0.04) GeV/ c at 200 GeV and (0.63±0.03) GeV/ c at 900 GeV in the central region and shows an increase with CM energy that is smore rapid than that expected from previous ISR data. The yield of kaons per inelastic p p event is found to be (0.72±0.12) at 200 GeV and (1.31±0.14) at 900 GeV. Finally, the K/π ratio has been found to exhibit a very slow increase with CM energy.

1 data table

No description provided.


No description provided.

No description provided.


Determination of $\alpha^- s$ From Energy-energy Correlations in $e^+ e^-$ Annihilation at 29-{GeV}

Wood, D.R. ; Petersen, A. ; Abrams, G.S. ; et al.
Phys.Rev.D 37 (1988) 3091, 1988.
Inspire Record 250899 DOI 10.17182/hepdata.23323

We have studied the energy-energy correlation in e+e− annihilation into hadrons at √s =29 GeV using the Mark II detector at the SLAC storage ring PEP. We find to O(αs2) that αs=0.158±0.003±0.008 if hadronization is described by string fragmentation. Independent fragmentation schemes give αs=0.10–0.14, and give poor agreement with the data. A leading-log shower fragmentation model is found to describe the data well.

6 data tables

Correlation data from the original PEP-5 detector.

Correlation Asymmetry data from the original PEP-5 detector.

Correlation data from the upgraded detector.

More…

Fragmentation of Ne-22 in Emulsion at 4.1-a/GeV/c

El-Naghy, A. ; Krasnov, S.A. ; Tolstov, K.D. ; et al.
J.Phys.G 14 (1988) 1125-1137, 1988.
Inspire Record 251875 DOI 10.17182/hepdata.39460

Charge distributions of projectile fragments produced in the interactions of 22Ne beams with emulsion at 4.1A GeV/c have been studied. Correlations between projectile and target fragments and among projectile fragments are presented. The change of charge yield distribution with the violence of the collision has been shown. The present analysis contradicts theoretical calculations describing the inclusive charge yield distribution of fragments by a single process.

4 data tables
More…

No description provided.

No description provided.

No description provided.

More…

UA5: A general study of proton-antiproton physics at s**(1/2) = 546-GeV

The UA5 collaboration Alner, G.J. ; Alpgard, K. ; Anderer, P. ; et al.
Phys.Rept. 154 (1987) 247-383, 1987.
Inspire Record 244829 DOI 10.17182/hepdata.19330

None

3 data tables

Mean charged multiplicity for NSD events extrapolated to the full phase space.

Charged particle pseudorapidity density for NSD events at pseudorapidiy = 0.

Corrected charged particle multiplicity distribution for NSD events.