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Elastic and total $\pi^{+}\pi^{-}$ cross-sections from a high statistics measurement of the reaction $\pi^{-}p \to \pi^{+}\pi^{-}n$ at 63 GeV/c

Weilhammer, P. ; Berglund, A. ; Chabaud, V. ; et al.

2 (1979) 628-635, 1979.

Inspire Record 148986 DOI 10.17182/hepdata.75420

A sample of about 230000 events of the reaction pi /sup -/p to pi /sup +/ pi /sup -/n, measured with a magnetic forward spectrometer set up in an unseparated pi /sup -/ beam with a momentum of 63 GeV/c at the SPS has been analysed in terms of one pion exchange. The elastic pi /sup +/ pi /sup -/ cross section has been determined using an extrapolation to the pion pole in the mass range up to m( pi /sup +/ pi /sup -/)=4 GeV. The total pi /sup +/ pi /sup -/ cross section is obtained via the optical theorem. (7 refs).

5 data tables

Table 1

INTEGRATED 2- S-WAVE INTENSITY FOR 1500 TO 1800 MEV, INCLUDING SIGNIFICANT BACKGROUND.

Table 2

No description provided.

Table 3

No description provided.

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ANTI-NEUTRINO - NUCLEON TOTAL CROSS-SECTION AND RATIO OF ANTI-NEUTRINO CROSS-SECTION ON NEUTRONS AND PROTONS

Erriquez, O. ; Fogli-Muciaccia, M.T. ; Natali, S. ; et al.

Phys.Lett.B 80 (1979) 309-313, 1979.

Inspire Record 143176 DOI 10.17182/hepdata.27366

On a selected sample of 2171 events, observed in the big heavy liquid bubble chamber Gargamelle at CERN, the charged current total cross section for antineutrino on nucleons has been determined up to the laboratory energy E v ̄ = 8 GeV . The total cross section is found to be a linear function of the antineutrino energy expressed by σ tot (E v ̄ ) = (0.26 ± 0.020) × 10 −38 × E v ̄ ( GeV ) cm 2 . The energy dependence of 〈q 2 〉 v ̄ is found to be given by 〈q 2 〉 v ̄ = (0.15 ± 0.04)E v ̄ + (0.05 ± 0.12) ( GeV /c) 2 . With a simplified nuclear model the ratio of cross sections on neutrons andprotons has been estimated as a function of energy and for two different values of the scaling variable x . The results are compared with the prediction of the naive quark parton model.

1 data table

Table 1

Measured charged current total cross section.

Coherent $K$(s) Regeneration on Protons From 30-{GeV}/$c$ to 130-{GeV}/$c$

Bock, G.J. ; Aronson, S.H. ; Freudenreich, K. ; et al.

Phys.Rev.Lett. 42 (1979) 350, 1979.

Inspire Record 7461 DOI 10.17182/hepdata.20779

Precise measurements att=0 of the KLp→KSp amplitude (modulus and phase) were made. Over 50000 Kπ2 decays along with normalizing Kμ3 events were detected behind a 7.2-m-long liquid-hydrogen regenerator. The momentum dependence of the modulus and phase are presented, and the results are combined with those of other experiments to extract the relevant parameters of ω exchange.

2 data tables

Table 1

RESULTS USING ETA+- = 2.15E-3.

Table 2

RESULTS USING ETA+- = 2.27E-3.

MEASUREMENT OF TWO AND THREE SPIN PARAMETERS AT 6-GEV/C USING A TRANSVERSELY POLARIZED BEAM AND TARGET

Beretvas, A. ; Miller, D. ; Auer, I.P. ; et al.

Phys.Rev.D 20 (1979) 21-32, 1979.

Inspire Record 146770 DOI 10.17182/hepdata.24227

Toward the goal of experimentally determining pp elastic scattering amplitudes at 6 GeV/c, we have measured a linear combination of triple-spin correlation parameters and also a linear combination of spintransfer parameters over the |t| range between 0.2 and 1.0 (GeV/c)2. A horizontally polarized beam (S direction) was obtained by precessing the spin of the polarized beam from the Argonne Zero Gradient Synchrotron using a superconducting solenoid. The target protons were polarized vertically (N direction) and the polarization of the recoil protons was measured with a carbon polarimeter. The results are consistent with the amplitude corresponding to π exchange being almost real and positive.

1 data table

Table 1

KSS = (S00S) AND HSNS = (SN0S) MEASURED HERE CONTAIN SMALL ADMIXTURES OF THE OTHER SPIN-TRANSFER AND TRIPLE-SPIN CORRELATION PARAMETERS RESPECTIVELY DUE TO THE POLARIZED TARGET MAGNETIC FIELD - SEE TEXT. MEAN VALUE OF HSNS OVER THIS T-RANGE IS 0.098 +- 0.085. PARITY CONSERVATION REQUIRES THE VANISHING OF THE PARAMETERS KSN, HSNN, (000S) AND DNS, WHILE (000N) MUST AGREE WITH THE SINGLE SCATTERING POLARIZATION PARAMETER (0N00).

Y* K AND Y* K* PRODUCTION IN pi+ p INTERACTIONS AT 10.3-GeV/c

Goddard, M.C. ; Key, A.W. ; Luste, G.J. ; et al.

Phys.Rev.D 19 (1979) 1350, 1979.

Inspire Record 7416 DOI 10.17182/hepdata.24321

The reactions π+p→Σ+(1385)K+ and π+p→Σ+(1385)K*+(890) are examined. The Σ+(1385)K+ differential cross section for −t′<0.5 GeV2 and spin density matrix elements agree with a Regge-pole model incorporating (nondegenerate) vector and tensor K* exchange with dominant M1 coupling. The Σ+(1385)K*+(890) density matrix elements are consistent with the quark-additivity predictions. A Y*+ at a mass of 1700 MeV is also observed in the Λπ+ mass distribution, produced opposite both K+ and K*+(890).

6 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

GOTTFRIED-JACKSON FRAME.

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INCLUSIVE PRODUCTION OF K*+- (890) AND SIGMA+- (1385) RESONANCES IN ANTI-P P INTERACTIONS AT 14.75-GEV/C

Canter, J. ; Chang, C.C ; Dao, F.T. ; et al.

Phys.Rev.D 20 (1979) 1029-1036, 1979.

Inspire Record 144992 DOI 10.17182/hepdata.24210

The inclusive and semi-inclusive cross sections for K*±(890) and Σ±(1385) resonances are determined in p¯p interactions at 14.75 GeV/c. They account for a large fraction of the KS0 and Λ0 produced. The K*-resonance production also affects the low-pT2 distribution of inclusive KS0. The x distributions of the resonance production are studied in terms of a simple quark-recombination model.

4 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Measurement of the Relative Total Hadronic Cross-section R at {PETRA}

The Aachen-DESY-Annecy(LAPP)-MIT-NIKHEF-Beijing collaboration Barber, D. ; Becker, U. ; Boehm, A. ; et al.

Phys.Rev.Lett. 42 (1979) 1113, 1979.

Inspire Record 140059 DOI 10.17182/hepdata.3235

We report the first measurement of the ratio R=(σe+e−→hadrons)(σe+e−→μ+μ−) (with negligible τ-lepton contribution) at a center-of-mass energy s=13 GeV and s=17 GeV, from the just finished electron-positron colliding-beam facility PETRA. The detector, MARK-J, has an approximately 4π solid angle and measures γ, e, μ, and charged and neutral hadrons simultaneously. Our results yield R(s=17 GeV)=4.9±0.6 (statistical) ±0.7 (systematic error), and R(s=13 GeV)=4.6±0.5 (statistical) ±0.7 (systematic error). The ratio R(s=17 GeV)R(s=13 GeV) is 1.08±0.18.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

RESULTS FROM DASP ON E+ E- ANNIHILATION BETWEEN 3.1-GEV AND 5.2-GEV

The DASP collaboration Brandelik, R. ; Braunschweig, W. ; Martyn, H.U. ; et al.

Z.Phys.C 1 (1979) 233-256, 1979.

Inspire Record 145403 DOI 10.17182/hepdata.16476

This paper summarizes the measurements one+e− annihilation performed by the DASP Collaboration in the energy range between 3.1 and 5.2 GeV. The following topics are covered: total cross section, production and two body decays of the narrow resonances, radiative decays of theJ/ψ and ψ′ resonances and evidence for theX(2.82), ψ′ cascade decays, inclusive η production and evidence for theF meson, semileptonic decays of charmed mesons and properties of the heavy lepton.

5 data tables

Table 1

THESE DATA ON R WERE PUBLISHED IN R. BRANDELIK ET AL., PL 76B, 361 (1978), THE RECORD OF WHICH HAS TABULATED CROSS SECTIONS WITH AND WITHOUT THE TAU HEAVY LEPTON CONTRIBUTION.

Table 2

OBSERVATION OF J/PSI RESONANCE.

Table 3

OBSERVATION OF PSI(3700)0 RESONANCE.