Chen, A.
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Pion Pair Production in Photon-photon Collisions at Dci

The DM1-DM2 collaboration Ajaltouni, Z. ; Falvard, A. ; Jousset, J. ; et al.
Phys.Lett.B 194 (1987) 573, 1987.
Inspire Record 248992 DOI 10.17182/hepdata.30109

This paper presents experimental results on π + π − production threshold from the collision of quasi-real photons. The data, obtained at the e + e − collider DCI, are a combination of the results from the DM1 and DM2 experiments. Using the e + e − and π + π − production for normalization and cross-checks, we observe a pion pair yield at low invariant mass ( W < 500 MeV/ c 2 ) which is approximately twice the one expected from Born terms.

2 data tables
Table 1

Data read from graph.

Table 2

Data read from graph.


OBSERVATION OF THE ASYMMETRY IN THE REACTION pi- p (polarized) ---> (pi0 pi0) n

Apokin, V.D. ; Belikov, N.I. ; Derevshchikov, A.A. ; et al.
Sov.J.Nucl.Phys. 47 (1988) 465, 1988.
Inspire Record 246899 DOI 10.17182/hepdata.40790

None

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Multiparticle Production in Proton - Nucleus Collisions at 360-{GeV}/$c$ Using the European Hybrid Spectrometer

The EHS-RCBC collaboration Bailly, J.L. ; Banerjee, S. ; Bartl, W. ; et al.
Z.Phys.C 35 (1987) 301, 1987.
Inspire Record 245414 DOI 10.17182/hepdata.15776

360 GeV/c proton interactions with aluminium (Al) and gold (Au) targets are studied using the European Hybrid Spectrometer (EHS) equipped with the Rapid Cycling Bubble Chamber (RCBC). Multiplicities, rapidity distributions and correlations between leading and other produced particles are presented and compared with Monte Carlo calculations based on the multi-chain and Lund models.

1 data table
Table 1

No description provided.


HIGH-ENERGY DIFFRACTION DISSOCIATION OF K0(L) INTO EXCLUSIVE FINAL STATES

Lamm, M.J. ; Wiss, J.E. ; Avery, P. ; et al.
Phys.Rev.D 36 (1987) 3341-3352, 1987.
Inspire Record 244943 DOI 10.17182/hepdata.23353

We have observed diffraction dissociation of KL0 mesons with a carbon target into the exclusive final states KS0π+π−, KS0ω, and KS0φ. The diffraction production cross section for these states is not strongly dependent on the incident energy, varying at most by 30% between 75 and 150 GeV. The mass distributions do not change appreciably as a function of laboratory energy. The ratio of the diffractive mass-threshold production of K*±π∓, KS0ρ, KS0ω, and KS0φ is compared with previously obtained lower-energy data.

4 data tables
Table 1

TP (=T-TMIN) distribution for K0S PI+ PI- events satisfying the diffractive cuts.

Table 2

TP distributions for K0S OMEGA and K0S PHI events which satisfy the diffractive cuts.

Table 3

CROSS SECTIONS PER NUCLEUS.

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Measurement of the Ratio of $\Sigma^0$ to $\Lambda^0$ Inclusive Production From 28.5-{GeV}/$c$ Protons on Beryllium

Sullivan, Marilyn W. ; Jensen, Douglas A. ; Kreisler, Michael N. ; et al.
Phys.Rev.D 36 (1987) 674, 1987.
Inspire Record 21321 DOI 10.17182/hepdata.23320

The ratio of the cross section for Σ0 inclusive production to the cross section for Λ0 inclusive production has been measured with 28.5-GeV/c protons incident on a beryllium target at an average laboratory production angle of 4°. This ratio was measured to be 0.278±0.011±0.05, where the uncertainties are statistical and systematic in that order. The ratio does not depend strongly on the momentum of the produced particle between 10 and 24 GeV/c. The effect of Σ0 contamination on previous determinations of the polarization of inclusively produced Λ0’s is discussed.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


$D$ Meson Production From 400 GeV/$c p p$ Interactions

The LEBC-EHS collaboration Aguilar-Benitez, M. ; Allison, W.W.M. ; Bailly, J.L. ; et al.
Phys.Lett.B 189 (1987) 476, 1987.
Inspire Record 245101 DOI 10.17182/hepdata.12913

We have measured the inclusive production properties of D and D messons produced from pp interactions at s =27.4 GeV . The differential production cross section is well represented by the empirical form d 2 σ d x F d P 2 T = 1 2 [σ ( D / D )(n+1)b](1−|x F |) n exp (−bp 2 T ) with n=4.9 ± 0.5, b=(1.0±0.1)( GeV /c) −2 , and the inclusive D / D cross section σ ( D / D ) is (30.2±3.3) ωb. The QCD fusion model predicts D / D production which is in good agreement with our data except for the magnitude of the cross section which depends sensitively on the assumed mass of the charm quark.

11 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Study of the Reaction $\bar{p} p \to \bar{\Lambda} \Lambda$ Near Threshold

Barnes, P.D. ; Besold, R. ; Birien, P. ; et al.
Phys.Lett.B 189 (1987) 249-253, 1987.
Inspire Record 244883 DOI 10.17182/hepdata.30178

Results are presented from a study of the reaction p p→ Λ Λ near threshold. Over 3000 events recorded at s values 14.6 and 25.5 MeV above the Λ Λ threshold (2231.2 MeV) have been analysed. Results for the production cross section, differential cross section, and the Λ and Λ polarization are given at both energies and are compared with recent theoretical calculations of this process.

3 data tables
Table 1

Statistical errors only.

Table 2

No description provided.

Table 3

No description provided.


A Measurement of the Muon Pair Production in $e^+ e^-$ Annihilation at 38.3-{GeV} $\le \sqrt{s} \le$ 46.8-{GeV}

The CELLO collaboration Behrend, H.J. ; Burger, J. ; Criegee, L. ; et al.
Phys.Lett.B 191 (1987) 209-216, 1987.
Inspire Record 244835 DOI 10.17182/hepdata.30180

The e + e − → μ + μ − reaction has been studied at centre of mass energies ranging between 38.3 abd 46.8 GeV with the CELLO detector at PETRA. We present results on the cross section and the charge asymmetry for this channel. Combining all the data at the average energy 〈 s 〉=43 GeV we obtain R μμ =〈 σ μμ / σ 0 〉=0.98±0.04±0.04, 〈 A μμ 〉=(−14.1±3.7±1.0)%, where σ 0 is the QED cross section and A μμ is the charge asymmetry corrected for pure radiative effects. These results are in good agreement with the expected values of R μμ =1.01 and A μμ =−14.5% at that energy.

3 data tables
Table 1

Mu-pair cross sections.

Table 2

Corrected angular distributions with data sample divided into two energy regions with means 39 and 44 GeV and total energy region.

Table 3

Forward-backward asymmetry.


THE STUDY OF THE DIFFRACTION PROCESSES IN THE anti-p p ---> anti-p p pi+ pi- pi0 REACTION AT 22.4-GeV/c

The Alma Ata-Dubna-Moscow-Prague-Sofiya-Helsinki collaboration Batyunya, B.V. ; Boguslavsky, I.V. ; Bruncko, D. ; et al.
Sov.J.Nucl.Phys. 47 (1988) 261, 1988.
Inspire Record 247861 DOI 10.17182/hepdata.38866

None

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Measurement of Anti-proton - Proton Small Angle Elastic Scattering at Low Momentum

Linssen, L. ; Beard, C.I. ; Birsa, R. ; et al.
Nucl.Phys.A 469 (1987) 726, 1987.
Inspire Record 245092 DOI 10.17182/hepdata.37014

Two high statistics measurements of antiproton-proton small-angle elastic scattering, at p = 233 MeV/ c and p = 272 MeV/ c , are presented. The measurements were carried out at the LEAR facility at CERN. By the Coulomb-nuclear interference method, values are obtained for the real-to-imaginary ratio ρ of the p̄p forward nuclear scattering amplitude and for its exponential slope b : ρ = + 0.041 ± 0.026 and b = 71.5 ± 4.5 (GeV/ c ) −2 at 233 MeV/ c and ρ = −0.014 ± 0.027 and b = 47.7 ± 2.7 (GeV/ c ) −2 at 272 MeV/ c . The method to derive these values is discussed in detail and so are the uncertainties contributing to their systematic error. The results are compared with predictions from forward dispersion relation calculations and with predictions from p̄p potential models.

3 data tables
Table 1

The corrected cross section is the measured divided by the average folding correction given in the paper.

Table 2

The corrected cross section is the measured divided by the average folding Correction given in the paper.

Table 3

Fits to data use the value of total cross sections of 263 & 296 mb for 272 & 233 Mev respectively derived from the authors total cross sections measurement. ETA is the spin dependence parameter.