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An Investigation of Multiplicity Distributions in Different Pseudorapidity Intervals in anti-p p Reactions at a CMS Energy of 540-GeV

The UA5 collaboration Alner, G.J. ; Alpgard, K. ; Anderer, P. ; et al.

Phys.Lett.B 160 (1985) 193-198, 1985.

Inspire Record 213986 DOI 10.17182/hepdata.6545

Multiplicity distributions of charged particles for inelastic, non single-diffractive events in proton-antiproton collisions at a centre of mass energy of 540 GeV are presented for various pseudorapidity (Δη) intervals. The widths of the multiplicity distributions, scaled to their means, increase as Δη is made smaller, and the deviation from a Poisson distribution becomes progressively more pronounced. It is found that the data are remarkably well described by a negative binomial distribution. The parameters of the distributions vary smoothly with the size of the acceptance interval.

31 data tables

Table 1

Data for full phase space.

Table 2

No description provided.

Table 3

No description provided.

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Inclusive Photoproduction of Strange Baryons at 20-{GeV}

The SLAC Hybrid Facility Photon collaboration Abe, K. ; Armenteros, R. ; Bacon, T.C. ; et al.

Phys.Rev.D 32 (1985) 2869-2882, 1985.

Inspire Record 213727 DOI 10.17182/hepdata.23548

Cross sections are presented for the inclusive photoproduction of KS0, Λ, Λ¯, Ξ−, Ξ¯−, Σ0, and Σ*±(1385) at 20 GeV. An upper limit to Ω− production is also given. The data come from 284 000 hadronic events photoproduced in the SLAC 1-m hydrogen-bubble-chamber hybrid facility exposed to a nearly monochromatic, polarized 20-GeV backscattered photon beam. A comparison of the KS0, Λ, Λ¯, and Ξ− rates per inelastic event to π±p data show that γp rates are consistent with being higher than the π±p rates, providing evidence of an ss¯ component of the photon. The pair cross sections for KS0KS0, KS0Λ, KSoΛ¯, and ΛΛ¯ are presented. The xF distributions of the Λ, Λ¯, and Ξ− are compared to a quark-diquark fusion model, giving information on strange-baryon photoproduction mechanisms.

1 data table

Table 1

No description provided.

Measurements of Triple and Double Spin Parameters in Elastic $p p$ Scattering at 6-{GeV}/$c$

Auer, I.P. ; Chalmers, J. ; Colton, E. ; et al.

Phys.Rev.D 32 (1985) 1609, 1985.

Inspire Record 213562 DOI 10.17182/hepdata.23547

Toward the goal of experimentally determining the p-p elastic-scattering amplitudes at 6 GeV/c, we have measured a number of triple- and double-spin correlation parameters over the ‖t‖ range between 0.2 and 1.0 (GeV/c)2. These new data permit the first nucleon-nucleon amplitude determination in the multi-GeV energy range. Polarized beams from the Argonne Zero Gradient Synchrotron and polarized targets were utilized. The polarization of the recoil proton was measured with a carbon polarimeter. A total of 14 different spin observables were measured (five spin transfer, four depolarization, and five triple-spin correlation parameters). These have been combined with earlier results, resulting in a data set of typically 30 measurements of 20 different spin observables for each of six ‖t‖ values between 0.2 and 1.0 (GeV/c)2. A solution for the amplitudes has been found at each ‖t‖, and comparisons are presented with several different models. The spin-nonflip helicity amplitudes are found to be much larger than the spin-flip amplitudes.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

Search for Fractionally Charged Particles Produced in $e^+ e^-$ Annihilation

The ARGUS collaboration Albrecht, H. ; Binder, U. ; Harder, G. ; et al.

Phys.Lett.B 156 (1985) 134-138, 1985.

Inspire Record 214357 DOI 10.17182/hepdata.45210

A search has been made for particles with charge Q = 1 3 , Q = 2 3 and Q = 4 3 produced in e + e − annihilation using the ARGUS detector at the e + e − storage ring DORIS, operating at a centre of mass energy around 10 GeV. No candidate events were found in 84.5 pb −1 of collected data. Upper limits are established for the cross section for the production of fractionally charged particles with masses up to 4 GeV c 2 , improving on previously obtained limits.

1 data table

Table 1

Two different models (I and II) are considered (see text).

Kaon production in $p$ reactions at a centre-of-mass energy of 540 GeV

The Bonn UA5 & Brussels UA5 & Cambridge UA5 & CERN UA5 & Stockholm UA5 collaborations Alner, G.J. ; Alpgard, K. ; Anderer, P. ; et al.

Nucl.Phys.B 258 (1985) 90624 505-539, 1985.

Inspire Record 214234 DOI 10.17182/hepdata.8127

Using the UA5 detector, the inclusive central production of Ks⁰ and K^± mesons has been measured in non-single-diffractive interactions at the CERN SPS $p$ Collider at a c.m. energy of 540 GeV. The average transverse momentum is found to be 〈pT〉 = 0.57±0.03 GeV/c in the rapidity range |y|<2.5, which is an increase of about 30% over the top ISR energy. The K/π ratio has increased from about 8% at ISR energies to 9.5±0.9±0.7% (the last error is systematic) at 540 GeV. The average number of Ks⁰ per non-single-diffractive event is 1.1±0.1 and the inclusive inelastic cross section is estimated at 49±5 mb.

6 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Neutral $K^*$ (890) and $\rho^0$ Meson Production in $e^+ e^-$ Annihilation at the $\sqrt{s}=29$-{GeV}

Derrick, M. ; Kooijman, P. ; Loos, J.S. ; et al.

Phys.Lett.B 158 (1985) 519-524, 1985.

Inspire Record 16663 DOI 10.17182/hepdata.30388

The production of neutral K ∗ (890) and ρ 0 mesons was studied in e + e − annihilation at s =29 GeV using the High Resolution Spectrometer at PEP. Differential cross sections are presented as a function of the scaled energy variable z and compared to π 0 and K 0 production. The measured multiplicities are 0.84±0.08 ϱ 0 mesons and 0.57±0.09 K ∗0 (890) mesons per event for a meson momentum greater than 725 MeV/ c . The ratios of vector meson to pseudoscalar meson production for (u,d), s and c quark are compared to predictions of the Lund model.

3 data tables

Table 1

Data requested from authors.

Table 2

No description provided.

Table 3

No description provided.

Upper Limit of B0 anti-B0 Mixing in e+ e- Annihilation at 29-GeV

Schaad, T. ; Nelson, M.E. ; Abrams, G. ; et al.

Phys.Lett.B 160 (1985) 188-192, 1985.

Inspire Record 214576 DOI 10.17182/hepdata.38117

None

1 data table

Table 1

Pt of the leptons is determined relative to the thrust axis. B-DECAY, C-DECAY, C-SECONDARY and BKG are corresponded to fractions of leptons originationg from primary BQ deacy, primary CQ decay, secondary decay, and from background.