HEPData Search

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Production of $\rho^\pm$, $G^\pm$(1700), $A2^\pm$, $K^{\pm}$(890) and $K^{\pm}$(1420) at 50-{GeV}/c

Delfosse, A. ; Dorsaz, P.A. ; Extermann, P. ; et al.

Nucl.Phys.B 183 (1981) 349-366, 1981.

Inspire Record 170363 DOI 10.17182/hepdata.34280

Mesons decaying into π 0 or η and one charged meson were studied using a liquid-argon calorimeter in a non-magnetic double-arm spectrometer. Cross sections and energy dependences are presented. The ϱ ± production mechanisms are discussed in detail: ω and π exchange contribute the largest fractions, but also A 2 exchange is present. ϱ ± production by ω exchange is shown to follow the energy behaviour predicted by the Regge trajectory α ω ( t ) = 0.4 − | t |.

2 data tables

Table 1

Axis error includes +- 0.0/0.0 contribution (13 TO 25////STATISTICAL ERRORS ARE SMALLER THAN THE SYSTEMATIC ERRORS).

Table 2

No description provided.

Lepton Pair Production and Search for a New Heavy Lepton in $e^+ e^-$ Annihilation

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

Phys.Lett.B 99 (1981) 489-494, 1981.

Inspire Record 164302 DOI 10.17182/hepdata.27110

We have measured the reaction ee → μμ and ee → ττ at center of mass energies from 9.4 to 31.6 GeV. The production cross sections are in agreement with the predictions of quantum electrodynamics, resulting in cutoff parameter limits of 70–100 GeV at 95% c.l. The branching ratio for τ → μν ν has been determined as [1.78 ± 2.0 (statist.) ± 1.8(syst.)]% The existence of a new sequential heavy lepton with a mass <14.5 GeV is excluded at 95% c.l.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

Observation of a $K \bar{K}$ Enhancement at 1.85-{GeV} in the Reaction $K^- P \to K \bar{K} \Lambda$ at 8.25-{GeV}/c

The BIRMINGHAM-CERN-GLASGOW-MICHIGAN STATE-PARIS collaboration Al- Harran, S. ; Amirzadeh, J. ; Baubillier, M. ; et al.

Phys.Lett.B 101 (1981) 357-360, 1981.

Inspire Record 170589 DOI 10.17182/hepdata.31206

In a high statistics ( ∼150 eV μb ) bubble chamber experiment on K − p interactions at 8.25 GeV c , the study of the reaction K − p → KK Λ provides evidence for an enhancement in the KK system with a mass of (1850 ± 10) MeV and a width of (80 −30 +40 ) MeV. Its possible identification with the missing isosinglet of the 3 − nonet is discussed. A K ∗ K decay mode is also observed.

1 data table

Table 1

No description provided.

$\Delta (\Sigma^-$l) and $\Delta$ (Sigma-t) Between 200-{MeV} and 520-{MeV}

Axen, D. ; Shypit, R. ; Comyn, M. ; et al.

J.Phys.G 7 (1981) L225-L230, 1981.

Inspire Record 171520 DOI 10.17182/hepdata.38530

New pp measurements of Delta sigma L and Delta sigma T between 200 and 520 MeV disagree with earlier Argonne data, and resolve discrepancies with inelastic data, phase-shift analysis and forward dispersion relations.

2 data tables

Table 1

TOTAL CROSS SECTION DIFFERENCE FOR PURE TRANSVERSE SPIN STATES (ANTIPARALLEL MINUS PARALLEL).

Table 2

TOTAL CROSS SECTION DIFFERENCE FOR PURE LONGITUDINAL SPIN STATES (ANTIPARALLEL MINUS PARALLEL).

Hadronic Cross-section in $e^+ e^-$ Annihilation From 1.45-{GeV} to 1.80-{GeV}

Esposito, B. ; Marini, A. ; Piano Mortari, Giovanni ; et al.

Lett.Nuovo Cim. 30 (1981) 65-71, 1981.

Inspire Record 170172 DOI 10.17182/hepdata.37368

None

2 data tables

Table 1

CROSS SECTION EXCLUDES ANY CONTRIBUTION FROM TWO-BODY FINAL STATES (PI+ PI- AND K+ K-).

Table 2

CHARGED AND NEUTRAL MULTIPLICITIES.

DELTA (1236) PRODUCTION IN ANTI-NEUTRINO n ---> mu+ n pi- REACTION AT HIGH-ENERGIES

Efremenko, V.I. ; Fedotov, A.V. ; Gorichev, P.A. ; et al.

ITEP-83-1981, 1981.

Inspire Record 167553 DOI 10.17182/hepdata.40191

None

5 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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BACKWARD PRODUCTION OF THE B (1235) MESON IN 11.46-GEV/C PI+ P INTERACTIONS

Wong, M.K. ; Key, A.W. ; Schwarzschild, B.M. ; et al.

Phys.Rev.Lett. 46 (1981) 974, 1981.

Inspire Record 169864 DOI 10.17182/hepdata.20643

Evidence for the backward production of the B(1235) meson in the final state π+p→pfπ+ω at 11.46 GeV/c with σ(|u′|<1.5 GeV2)=1.28±0.26 μb is presented. When nucleon exchange is assumed to dominate, estimates for the SU(3) mixing parameter FD as well as the B coupling to the nucleon-antinucleon are given. Some indication of a narrow enhancement at M(π+ω)≃1.03 GeV/c2 is seen, but confirmation of this as a resonant state is not yet possible.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

REACTION K- P ---> ANTI-K0 P PI- AT 6.5-GeV/c

Toaff, S. ; Musgrave, B. ; Phelan, J.J. ; et al.

Phys.Rev.D 23 (1981) 1500-1513, 1981.

Inspire Record 167202 DOI 10.17182/hepdata.24089

Data from the ANL 12-foot bubble chamber have been used to study the K¯0π− system in the reaction K−p→K¯0pπ− at 6.5 GeV/c. Signals for the production of K*(892), K*(1430), and K*(1780) were observed with cross sections of 181±22, 41.2±6, and 8.4±2.9 ≥b, respectively. The partial waves contributing to the production of the K¯0π− system from threshold up to 1.7 GeV were studied. The principal conclusions are: (i) K*(892) and K*(1430) production is dominated by natural-parity exchange, (ii) the ratio of unnatural- to natural-parity exchange increases with the resonance mass, consistent with the predictions of a triple-Regge model, (iii) there is evidence for a broad 0+ s-wave enhancement, with considerable s−d and s−p interference, centered at 1.2 GeV, and (iv) the m=2 amplitudes are negligible.

3 data tables

Table 1

<AK0 PI-> EFFECTIVE-MASS DISTRIBUTION FITTED WITH BREIT-WIGNER FUNCTIONS AND CUBIC POLYNOMIAL BACKGROUND. FITTED MASS OF KN(1800)- IS 1762 +- 9 MEV.

Table 2

THE LARGE BACKGROUND UNDER THE K*(1420)- IS SUBTRACTED USING A LINEAR FIT.

Table 3

NOT CORRECTED FOR PRESENCE OF BACKGROUND.