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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.

rivet Analysis
A Study of Photon Production in Hadronic $e^+ e^-$ Annihilation

The JADE collaboration Bartel, W. ; Becker, L. ; Cords, D. ; et al.

Z.Phys.C 28 (1985) 343, 1985.

Inspire Record 213948 DOI 10.17182/hepdata.16076

The production of photons ine+e−→γ+hadrons is investigated at three centre of mass energies around 14, 22 and 34 GeV. On average, photons carry 25% of the total available energy, with a multiplicity similar to the charged multiplicity. The inclusive photon spectra are found to scale with the centre of mass energy as a function of the Feynman variablex. π0 and η mesons are reconstructed from their decay photons. The slopes of the spectra are similar to that for charged pions and approximate scaling is observed for π0 production. The mean π0 and η multiplicities are given. The observed photon yield can be fully accounted for by hadron decays and initial state radiation. However, up to one extra photon per event from other sources cannot be excluded.

8 data tables

Table 1

No description provided.

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$\psi \psi$ Production and Limits on Beauty Meson Production From 400-{GeV}/$c$ Protons

The NA3 collaboration Badier, J. ; Boucrot, J. ; Bourotte, J. ; et al.

Phys.Lett.B 158 (1985) 85, 1985.

Inspire Record 213878 DOI 10.17182/hepdata.30379

From a study of multimuon events obtained in a high luminosity proton-platinum experiment at 400 GeV/ c , we find 5 ± 4 ψψ events, which correspond to a production cross section σ ( ψψ = 27 ± 10 pb. The observed production is compared to the ψψ events previously found in the same apparatus from incoming π − ; a comparison with QCD predictions is performed, giving a good agreement with expectations from gluon-gluon fusion. Finally, using like-sign dimuon, trimuon and quadrimuon events, we give model-dependent upper limits on beauty meson production: 2 nb/nucleon for central models, 20 nb/nucleon for diffractive production.

1 data table

Table 1

No description provided.

Observation of Anti-deuteron Production in Electron - Positron Annihilation at 10-{GeV} Center-of-mass Energy

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

Phys.Lett.B 157 (1985) 326-332, 1985.

Inspire Record 214358 DOI 10.17182/hepdata.30409

The production of antideuterons has been observed in electron-positron annihilations at center-of-mass energies around 10 GeV. Antideuterons have been identified unambiguously by their energy loss in the drift chamber, their time-of-flight and the pattern of their energy deposition in the shower counters of the ARGUS detector. The production rate in the momentum range (0.6−1.8) GeV/ c is (1.6 −0.7 +1.0 ) × 10 −5 per hadronic event.

2 data tables

Table 1

Results from 6 antideuterons detected (3 from UPSI(2S), 2 from (IS) and 1 from (4S)).

Table 2

No description provided.

A comparison of direct photon, $\pi^0$, and $\eta$ production in $p\bar{p}$p and $pp$ interactions at the CERN ISR

The Axial Field Spectrometer collaboration Akesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.

Phys.Lett.B 158 (1985) 282-288, 1985.

Inspire Record 213984 DOI 10.17182/hepdata.30391

We have measured the production of direct photons, π 0 's, and η's in p p and pp collisions at √ s =53 GeV in the range 2≈ p T ≈6 GeV/ c for the central rapidity region | y | 0.4. No statistically significant difference between pp̄ and pp interactions is observed.

5 data tables

Table 1

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rivet Analysis
Production of $\phi$ and F (1970) $\to \phi \pi$ in $e^+ e^-$ Annihilation at 29-{GeV}

Derrick, M. ; Fernandez, E. ; Fries, R. ; et al.

Phys.Rev.Lett. 54 (1985) 2568, 1985.

Inspire Record 213242 DOI 10.17182/hepdata.20340

Data from the high-resolution spectrometer at PEP have been used to study the inclusive production of φ mesons and F± mesons decaying into φπ±. Fragmentation functions and cross sections are presented and compared to existing data. The total φ cross section at 29 GeV is 40±6 pb. The observed F signal in the region z>0.4, given the assumption that R(F)[R(F)+R(D)]=0.15, corresponds to an F→φπ branching ratio of (3.3±1.1)%. The measured F mass is 1963±3±3 MeV/c2.

5 data tables

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WITH THE FOLLOWING ANGLE CUTS ON THE DECAY REGIONS. PHI DECAY - ABS(COS(THETA)) >0.5.

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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).

Elastic Scattering at the {CERN} {SPS} Collider Up to a Four Momentum Transfer of 1.55-{GeV}**2

The UA4 collaboration Bozzo, M. ; Braccini, P.L. ; Carbonara, F. ; et al.

Phys.Lett.B 155 (1985) 197-202, 1985.

Inspire Record 213385 DOI 10.17182/hepdata.30410

Proton-antiproton elastic scattering was measured at the center-of-mass energy s =546 GeV in the four-momentum transfer range 0.45⩽−⩽1.55GeV 2 . The shape of the t -distribution is quite different from that observed in proton-proton scattering at the ISR. Rather than a dip-bump structure, a kink is present at − ≈0.9GeV 2 followed by a shoulder. The cross section at the second maximum is more than one order of magnitude higher than at the ISR.

1 data table

Table 1

No description provided.

Multiplicities of charged hadrons in 280 GeV/c muon-proton scattering

The European Muon collaboration Arneodo, M. ; Arvidson, A. ; Aubert, J.J. ; et al.

Nucl.Phys.B 258 (1985) 90611 249-266, 1985.

Inspire Record 213391 DOI 10.17182/hepdata.33787

Properties of the hadron multiplicity distributions in 280 GeV/c μ⁺p interactions have been investigated. The c.m. energy dependence in the range from 4 to 20 GeV of the total charged multiplicities are presented. No variation faster than logarithmic is seen in the energy range of this experiment. Comparison with νp and $ν p$ data at lower energy has been made and shows good agreement between μ⁺p and $ν p$ total charged multiplicities. It has been found that the average forward multiplicity (charged hadrons with xF > 0) exceeds the average backward multiplicity (charged hadrons with xF < 0) in the whole energy range and presents a different energy variation. The average forward multiplicity has been compared to e⁺e⁻ data and shows a similar dependence on energy. Little correlation was observed between the forward and backward multiplicities indicating that the current and target regions fragment almost independently.

8 data tables

Table 1

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