Date

Scaling of Pseudorapidity Distributions at c.m. Energies Up to 0.9-TeV

The UA5 collaboration Alner, G.J. ; Ansorge, R.E. ; Asman, B. ; et al.
Z.Phys.C 33 (1986) 1-6, 1986.
Inspire Record 233599 DOI 10.17182/hepdata.15816

New data are presented on charged particle pseudorapidity distributions for inelastic events produced at c.m. energies\(\sqrt s \)=200 and 900 GeV. The data were obtained at the CERN antiproton-proton Collider operated in a new pulsed mode. The rise of the central density ρ(0) at energies up to\(\sqrt s \)=900 GeV has been studied. A new form of central region scaling is found involving the densityρn(0) for charged multiplicityn, namely that the scaled central densityρn(0)/ρ(0) expressed as a function ofz=n/〈n〉 is independent ofs. Scaling in the fragmentation region holds to 10–20%, and the small amount of scalebreaking observed here could be accommodated within the framework suggested by Wdowcyk and Wolfendale to account for both accelerator and cosmic ray data.

4 data tables
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Observation of $\Xi^-$ Production in $e^+ e^-$ Annihilation at 29-{GeV}

Klein, S. ; Himel, T. ; Abrams, G.S. ; et al.
Phys.Rev.Lett. 58 (1987) 644, 1987.
Inspire Record 234976 DOI 10.17182/hepdata.20187

Inclusive Ξ− production in e+e− annihilation at 29 GeV has been measured with the Mark II detector. From an integrated luminosity of 207 pb−1, we determine a production rate of 0.017±0.004±0.004 Ξ−+Ξ¯+ per hadronic event. A search for Ξ*0(1530)→Ξ−π+ leads to an upper limit of N(Ξ*0)/N(Ξ−)<0.35 at a 90% confidence level.

2 data tables

Numerical values supplied by S. Klein.

Extrapolation over full x range using LUND Monte Carlo.


Inclusive Charm Cross-Sections in 800-GeV/c p p Interactions

The LEBC-MPS collaboration Ammar, R. ; Banerjee, S. ; Baland, J.F. ; et al.
Phys.Lett.B 183 (1987) 110, 1987.
Inspire Record 233423 DOI 10.17182/hepdata.42573

We report a measurement of the inclusive D/D̄ production cross section in 800 GeV/ c proton-proton interactions. The experiment used the high resolution bubble chamber LEBC exposed to an 800 GeV/ c proton beam at the Fermilab MPS. We obtain σ( D/ D ̄ )=59 −15 +22 μ b (statistical errors), having analysed 25% of the total data sample. Comparison with 400 GeV/ c pp dat a obtained with LEBC at CERN shows a D/D̄ cross section increase by a factor of 1.7 −0.5 +0.7 . This is in good agreement with fusion model calculations.

7 data tables

No description provided.

No description provided.

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Asymmetry in the Angular Distribution of Inclusive $\Lambda$ Baryons From $e^+ e^-$ Annihilations at $\sqrt{s}=29$-{GeV}

Abachi, S. ; Baringer, Philip S. ; Bylsma, B.G. ; et al.
Phys.Lett.B 181 (1986) 403-406, 1986.
Inspire Record 18955 DOI 10.17182/hepdata.30215

A forward-backward asymmetry A , consistent with that expected from the γ − Z 0 interference term in the process e + e − → q q , is observed in the laboratory production angular distribution of high-momentum ∧ baryons. The data were collected with the High Resolution Spectrometer at PEP. The asymmetry for ∧ baryons with fractional energy z= 2E s greater than 0.3 is A = (−23± 8 plusmn ; 2)%.

2 data tables

No description provided.

Data read from graph.


Observation of Charge Asymmetry in Hadron Jets From $e^+ e^-$ Annihilation at $\sqrt{s}=29$-{GeV}

Ash, W. ; Band, H. ; Camporesi, T. ; et al.
Phys.Rev.Lett. 58 (1987) 1080, 1987.
Inspire Record 231267 DOI 10.17182/hepdata.20184

A charge asymmetry has been observed in final-state jets from e+e− annihilation into hadrons at √s =29 GeV. The measured asymmetry is consistent with the prediction of electroweak theory. The product of axial-vector weak coupling constants, averaged over all quark flavors, is determined to be 〈gAegAq〉=-0.34±0.06±0.05.

1 data table

Measured differential cross section after efficiency and radiative cross sections. THETA is the polar-angle of the thrust axis defined to be the angle between the direction of the incident positron and the thrust axis taken in the direction of the positron jet. Numerical values requested from the authors. Data are normalised to the total expected QED cross section.


Observation of Tensor and Scalar Mesons Produced in $e^+ e^-$ Annihilation at 29-{GeV}

Abachi, S. ; Baringer, Philip S. ; Bylsma, B.G. ; et al.
Phys.Rev.Lett. 57 (1986) 1990, 1986.
Inspire Record 18688 DOI 10.17182/hepdata.20227

The production of the tensor mesons f0(1270) and K*0(1430) and the scalar meson S(975) has been observed in e+e− annihilation at 29 GeV center-of-mass energy by use of data obtained with the high-resolution spectrometer at the SLAC e+e− storage ring PEP. The mean multiplicities for meson momenta greater than 1450 MeV/c are 〈nf0〉=0.11±0.04, 〈nK*0(1430)〉=0.10±0.06, and 〈nS〉=0.05±0.02 per hadronic event. The fragmentation functions of the tensor mesons are in good agreement with the predictions of the Webber cluster model. The data are consistent with a predominant strange-quark content on the S meson.

2 data tables

No description provided.

No description provided.


Inclusive $\eta$ Production at Low Transverse Momentum in 63-{GeV} $p p$ Collisions at the {CERN} Intersecting Storage Rings

The Axial Field Spectrometer collaboration Akesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Phys.Lett.B 178 (1986) 447, 1986.
Inspire Record 230636 DOI 10.17182/hepdata.30230

The inclusive production of η-mesons in pp collisions at √ s =63GeV and ϑ CM =90° has been measured for p T <1.5GeV/c. The η/π ratio decreases from its previously measured asymptotic value of η/π ∼ 0.5 at high transverse momentum, to η/π ≈0.3 at P T = 750MeV/c and η/π ≈ 0.01 at P T =300MeV/c, in a way that consistent with phase-space considerations, e.g. m T scaling. The η/π ratio, integrated from 0.2–1.5 GeV/ c , is found to be η/π=0.07±0.055.

1 data table

No description provided.


Angular Distributions for High Mass Jet Pairs and a Limit on the Energy Scale of Compositeness for Quarks from the CERN p anti-p Collider

The UA1 collaboration Arnison, G. ; Albajar, C. ; Albrow, M.G. ; et al.
Phys.Lett.B 177 (1986) 244-250, 1986.
Inspire Record 230633 DOI 10.17182/hepdata.30248

Angular distributions of high-mass jet pairs (180< m 2 J <350 GeV) have been measured in the UA1 experiment at the CERN pp̄ Collider ( s =630 GeV ) . We show that angular distributions are independent of the subprocess centre-of-mass (CM) energy over this range, and use the data to put constraints on the definition of the Q 2 scale. The distribution for the very high mass jet pairs (240< m 2 J <300 GeV) has also been used to obtain a lower limit on the energy scale Λ c of compositeness of quarks. We find Λ c >415 GeV at 95% confidence level.

2 data tables

No description provided.

No description provided.


COMPARISON OF THE PARTICLE FLOW IN q anti-q g AND q anti-q gamma EVENTS IN e+ e- ANNIHILATION

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Avery, R.E. ; et al.
Phys.Rev.Lett. 57 (1986) 945, 1986.
Inspire Record 230224 DOI 10.17182/hepdata.38183

We compare the particle flow in the event plane of three-jet qq¯g (quark-antiquark-gluon) events with the particle flow in radiative annihilation events qq¯γ (quark-antiquark-photon) for similar kinematic configurations. In the angular region between quark and antiquark jet, we find a significant decrease in particle density for qq¯g as compared to qq¯γ. This effect is predicted in QCD as a result of destructive interference between soft-gluon radiation from quark, antiquark, and hard gluon.

2 data tables

No description provided.

No description provided.


PRODUCTION OF BACKWARD PROTONS IN LAB SYSTEM WITH 0.2-GeV/c - 0.5-GeV/c MOMENTA IN anti-p A INTERACTIONS AT 40-GeV/c

Gabunia, L.L. ; Dzhavrishvili, A.K. ; Ivanova, A.B. ; et al.
Yad.Fiz. 46 (1987) 540-548, 1987.
Inspire Record 236228 DOI 10.17182/hepdata.39002

None

14 data tables

NUCLEUS IS C6J.

NUCLEUS IS C6J.

NUCLEUS IS C6J.

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