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Measurement of Jet Production Properties at the CERN anti-p p Collider

The UA2 & Bern-CERN-Copenhagen-Orsay-Pavia-Saclay collaborations Bagnaia, P. ; Banner, M. ; Battiston, R. ; et al.

Phys.Lett.B 144 (1984) 283-290, 1984.

Inspire Record 202658 DOI 10.17182/hepdata.30516

Jet production properties at s = 540 GeV have been measured in the UA2 detector at the CERN p p Collider. Results on the total transverse momentum of the jet system, on the parton density in the nucleon (structure function) and on the two-jet angular distributions are reported. The data are compared with QCD predictions and extrapolations from lower energy experiments.

2 data tables

Table 1

DISTRIBUTION OF THE SCATTERING ANGLE OF THE 2-JET AXIS IN THE 2-JET COM FRAME WITH A NORMALISATION FIXED AT 1 FOR COS(THETA*) = 0.

Table 2

STRUCTURE FUNCTION IS DEFINED AS F(X) WHERE D3(SIG)/DX1/DX2/DCOS(THETA) = (F(X1)/X1)*(F(X2)/X2)*D(SIG)/DCOS(THETA).

Near-threshold photoproduction of $\Lambda(1520)$ from protons and deuterons

Muramatsu, N. ; Chen, J.Y. ; Chang, W.C. ; et al.

Phys.Rev.Lett. 103 (2009) 012001, 2009.

Inspire Record 817890 DOI 10.17182/hepdata.22937

Photoproduction of $\Lambda$(1520) with liquid hydrogen and deuterium targets was examined at photon energies below 2.4 GeV in the SPring-8/LEPS experiment. For the first time, the differential cross sections were measured at low energies and with a deuterium target. A large asymmetry of the production cross sections from protons and neutrons was observed at backward K$^{+/0}$ angles. This suggests the importance of the contact term, which coexists with t-channel K exchange under gauge invariance. This interpretation was compatible with the differential cross sections, decay asymmetry, and photon beam asymmetry measured in the production from protons at forward K$^+$ angles.

4 data tables

Table 1

The measured differential cross sections from the liquid hydrogen target, protons, as a function the K+ polar angle.

Table 2

The measured differential cross sections from the liquid hydrogen target, protons, as a function the photon energy at forward K+ polar angles of 19-43 degrees .

Table 3

The measured of differential cross section at backward K+/K0 polar angles of 120-150 degrees as a function of photon energy from the liquid hydrogen target, protons, and liquid deuterium target, deuterons.

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Central Collisions of 800-{GeV} Protons With Ag / Br Nuclei in Nuclear Emulsion

The BATON ROUGE-KRAKOW-MOSCOW-TASHKENT collaboration Abduzhamilov, A. ; Barbier, L.M. ; Chernova, L.P. ; et al.

Phys.Rev.D 39 (1989) 86-91, 1989.

Inspire Record 280844 DOI 10.17182/hepdata.3813

Central collisions of 800-GeV protons with the heavy components of nuclear emulsion, Ag107 and Br80, have been investigated to determine the characteristics of small-impact-parameter collisions and, by comparison with the analysis of inclusive proton-emulsion inelastic interactions and inelastic proton-nucleon collisions, to study the dependence of the interaction process on the mean number of intranuclear collisions 〈ν〉. The data are also compared with the results obtained in proton-emulsion collisions, both central and inclusive, at 200 GeV. The variations in the secondary-particle multiplicities and the normalized pseudorapidity density correlate with 〈ν〉 and demonstrate that proton-nucleus interactions, both central and inclusive, can be described adequately by the incoherent superposition of proton-nucleon collisions.

5 data tables

Table 1

NUCLEUS IS AVERAGE NUCLEUS OF EMULSION.

Table 2

NUCLEUS IS AVERAGE NUCLEUS OF EMULSION.

Table 3

NUCLEUS IS AVERAGE NUCLEUS OF EMULSION.

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Two Particle Correlations in $e^+ e^-$ Annihilation

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.

Phys.Lett.B 90 (1980) 312, 1980.

Inspire Record 144112 DOI 10.17182/hepdata.27256

We present measurements of two-particle angular correlations in hadron jets produced in e + e − annihilation between 7.7 and 31.6 GeV c.m. energy. The data are compared to predictions of high order perturbative QCD calculations.

1 data table

Table 1

No description provided.

DIFFRACTIVE PRODUCTION OF A NARROW BARYON IN NEUTRON CARBON INTERACTIONS

The BIS-2 collaboration Aleev, A.N. ; Arefev, V.A. ; Balandin, V.P. ; et al.

Dubna Jinr - 83-602 (83,REC.NOV.) 6p, 1983.

Inspire Record 196394 DOI 10.17182/hepdata.39600

None

6 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Production of $\pi^0 \pi^0$ and $\pi^0 \eta$ in Photon - Photon Collisions

Edwards, C. ; Partridge, Richard ; Peck, C. ; et al.

Phys.Lett.B 110 (1982) 82-86, 1982.

Inspire Record 168793 DOI 10.17182/hepdata.30959

We investigate the four-photon final state produced in γγ colissions. In the π 0 π 0 channel we observe f(1270) production with predominantly helicity 2 and measure a partial width Γ γγ 2.9 +0.6 −0.4 ± keV (independent of assumptions on the helicity). We observe A 2 (1310) production in the π 0 η channel and find a partial width Γ γγ = 0.77 ± 0.18 ± 0.27 KeV (assuming helicity 2). We give an upper limit for f ≈ ηη .

3 data tables

Table 1

Data read from graph. Systematic error on M is of order of 2% or less.

Table 2

Data read from graph.

Table 3

No description provided.

Exclusive Production of Hadron Pairs at Large Momentum Transfer in Photon-photon Interactions

The PLUTO collaboration Berger, Christoph ; Deuter, A. ; Genzel, H. ; et al.

Phys.Lett.B 137 (1984) 267-271, 1984.

Inspire Record 194772 DOI 10.17182/hepdata.30576

We report on the exclusive production of π, K and proton pairs from photon-photon interactions at momentum transfers | t |⩾1 GeV 2 . Using the PLUTO detector at the e + e − storage ring PETRA, we have observed 15 events in an integrated luminosity of 41.7 pb −1 . The data lie far below the expectations for point-like hadrons, and are in reasonable agreement with the QCD-based predictions of Brodsky and Lepage.

3 data tables

Table 1

THIS METHOD OF ANALYSIS OF THE OBSERVED RATIO OF HADRON TO MUON PAIRS, IS TIED TO THE SPECIFIC DETECTOR ACCEPTANCE, BUT HAS THE ADVANTAGE OF BEING VIRTUALLY INDEPENDENT OF THE HADRON MASSES.

Table 2

SEE COMMENT IN PREVIOUS TABLE.

Table 3

THIS METHOD OF ANALYSIS OF THE CROSS SECTION AT 90 DEG IN THE CM AS A FUNCTION OF PCM IS MORE EASILY COMPARED WITH THEORETICAL PREDICTIONS BUT MORE DEPENDENT ON THE SPECIFIC HADRON MASSES.

CHARACTERISTICS OF SECONDARY PROTONS FROM INELASTIC INTERACTIONS OF PROTONS WITH NE NUCLEI AND NUCLEONS AT THE MOMENTUM P = 300-GEV/C. (IN RUSSIAN)

Allaberdin, M.L. ; Inogamova, T.Ya. ; Kosonovsky, E.A. ; et al.

Yad.Fiz. 39 (1984) 662-674, 1984.

Inspire Record 206660 DOI 10.17182/hepdata.2646

None

19 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Production of the F(0) Meson in Photon-photon Collisions

The CELLO collaboration Behrend, H.J. ; Fenner, H. ; Schachter, M.J. ; et al.

Z.Phys.C 23 (1984) 223, 1984.

Inspire Record 199731 DOI 10.17182/hepdata.16320

The production of thef0 in two photon collisions, with the subsequent decayf0→π+π− has been observed in the CELLO detector at PETRA. Thef0 peak was found to lie on a dipion continuum and to be shifted downwards in mass by ≃50 MeV/c2. The ππ mass spectrum from 0.8 to 1.5 GeV/c2 was well fitted by the model of Mennessier using only a unitarised Born amplitude and helicity 2f0 amplitude. The previously observed mass shift and distortion of thef0 peak are explained by strong interference between the Born andf0 amplitudes. The only free parameter in the fit of the data to the model is the radiative widthΓγγ(f0). It was found that:Γγγ(f0)=2.5±0.1±0.5 keV where the first (second) quoted errors are statistical (systematic).

2 data tables

Table 1

Data read from graph.

Table 2

Data read from graph.