Lai, Kwan-Wu
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Production of the g(1640) Meson in pi p Interactions at 6 GeV/c

Crennell, D.J. ; Karshon, U. ; Lai, K.W. ; et al.
Phys.Lett.B 28 (1968) 136-139, 1968.
Inspire Record 54727 DOI 10.17182/hepdata.29107

We present the results of a spin determination of the g 1 − (1640) meson from an analysis of its dipion decay mode (π − π 0 ), and find that spin three (or maybe greater) is favored [1,2]. We also report on the observation of an isospin one KK̄ enhancement at 1640 MeV which is consistent with a new decay mode of the g meson. A relative branching ratio of (K K ̄ /ππ) = 8 ± 3 8 % is obtain from our analysis.

2 data tables
Table 1

The values of the cross sections were presented for reactions with KS finalstates for visible KS decays only.

Table 2

The cross section value is corrected for invisible KS decay.


Two-body strange-particle final states in pi- p interactions at 4.5 and 6 gev/c

Crennell, D.J. ; Gordon, H.A. ; Lai, Kwan-Wu ; et al.
Phys.Rev.D 6 (1972) 1220-1254, 1972.
Inspire Record 73936 DOI 10.17182/hepdata.3601

Results on the following π−p reactions involving a hyperon are studied at 4.5 and 6.0 GeV/c from a high-statistics bubble-chamber experiment. (1) π−p→(Λ, Σ0)K0: Differential cross sections and hyperon polarizations are presented. Comparison with the line-reversed reactions K¯N→(Λ, Σ0)π indicates the failure of the predictions of K*(890) and K*(1420) exchange degeneracy. Effective trajectories for these two reactions are compared. Shrinkage is observed in K¯N→Λπ and not in π−p→ΛK0. (2) π−p→(Λ, Σ0)K*(890)0: Differential cross sections, hyperon polarizations, and K*(890)0 density-matrix elements are determined. ΛK*(890)0 decay correlations are found to impose strong constraints on the scattering amplitudes. The data indicate that both natural- and unnatural-parity exchanges contribute large, but opposite, Λ polarizations. This behavior cannot be explained by a simple exchange model utilizing K and the exchange-degenerate K*(890) and K*(1420) only. Additional trajectories or absorption effects are required to obtain the observed Λ-polarization effects. Comparison of ΛK*(890)0 and Σ0K*(890)0 indicates the greater importance of unnatural-parity exchange in the former reaction. We observe no evidence for deviations from isospin predictions in ΛK*(890)0 production where K*(890)0→K+π− and KS0π0. (3) π−p→ΛK*(1420)0 and ΛK*(1300)0: K*(1420)0 density-matrix elements satisfying positivity constraints are determined allowing for s-wave interference effects. Evidence of the existence of a narrow K*(1300)0→Kππ with a dominant K+ρ− decay mode is observed in the 4.5- and 6-GeV/c data. (4) Σ(1385), Λ(1405), Λ(1520) production: Differential cross sections for the quasi-two-body reactions π−p→Y0K0, where Y0 is Λ(1405), Λ(1520), or Σ(1385)0, are presented and found to have a very similar flat slope in the forward direction. Data for forward K+ scattering in the reaction π−p→Σ(1385)−K+ are presented and discussed. It is argued that this forward peak cannot be explained by kinematic reflection or an s-channel effect and therefore must be due to either two-particle exchange or a single exotic exchange in the t channel.

39 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

FIT FOR FORWARD CROSS SECTION AND SLOPE.

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Strange Particle Cross-Sections from pi+ p Interactions at 10.3-GeV/c

Goddard, M.C. ; Gilbert, D. ; Key, A.W. ; et al.
Phys.Rev.D 16 (1977) 7, 1977.
Inspire Record 5358 DOI 10.17182/hepdata.24450

Cross sections are presented for production of final states with two strange particles from π+p interactions at 10.3 GeV/c in a 31.1-event/μb bubble-chamber experiment.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Production and Decay of a High Mass I = 3/2 Baryon Enhancement in 10.3-GeV/c pi+ p Interactions

Zemany, P.D. ; Beaufays, J. ; Goddard, M.C. ; et al.
Nucl.Phys.B 137 (1978) 365-376, 1978.
Inspire Record 5279 DOI 10.17182/hepdata.35058

A high-mass Δ resonance is observed in several final states from π + p interactions at 10.3 GeV/ c . We obtain fitted mass and width values for this structure of 1871 ± 22 MeV and 205 ± 43 MeV, respectively. The branching ratios for decays to π + p, p π + π 0 , n π + π + and Σ + K + are found to be 0.48 ± 0.15, 0.26 ± 0.07, 0.24 ± 0.07 and 0.03 ± 0.01, respectively. The Δϱ, Δω differential cross sections and the ϱ 0 density matrix elements are examined.

3 data tables
Table 1

DEL(1950B) (OR DEL(1880B)) FITTED WITH BRIET-WIGNER RESONANCE AND POLYNOMIAL BACKGROUND.

Table 2

No description provided.

Table 3

No description provided.


rivet Analysis
Observation of a Resonance in e+ e- Annihilation Just Above Charm Threshold

Rapidis, Petros A. ; Gobbi, B. ; Luke, D. ; et al.
Phys.Rev.Lett. 39 (1977) 526, 1977.
Inspire Record 119979 DOI 10.17182/hepdata.20971

We observe a resonance in the total cross section for hadron production in e+e− annihilation at a mass of 3772±6 MeV/c2 having a total width of 28±5 MeV/c2 and a partial width to electron pairs of 370±90 eV/c2.

2 data tables
Table 1

BEFORE ANY RADIATIVE CORRECTIONS.

Table 2

AFTER APPLYING ALL RADIATIVE CORRECTIONS.


Study of D Mesons Produced in the Decay of the psi-prime-prime (3772)

Peruzzi, I. ; Piccolo, M. ; Feldman, G.J. ; et al.
Phys.Rev.Lett. 39 (1977) 1301, 1977.
Inspire Record 120878 DOI 10.17182/hepdata.21003

From a study of D mesons produced in the decay ψ(3772)→DD¯, we have determined the masses of the D0 and D+ mesons to be 1863.3±0.9 MeV/c2 and 1868.3±0.9 MeV/c2, respectively. Under the assumption that the ψ(3772) has a definite isospin and decays only to DD¯, the D0 branching fractions to K−π+, K¯0π+π−, and K−π+π−π+ are (2.2±0.6)%, (4.0 ± 1.3)%, and (3.2±1.1)% and the D+ branching fractions to K¯0π+ and K−π+π+ are (1.5±0.6)% and (3.9±1.0)%.

1 data table
Table 1

AROUND PSI(3772)0 PEAK. UPPER BOUNDS EACH SIDE OF PEAK ARE TABULATED IN M. PICCOLO ET AL., PL 86B, 220 (1979).


Inclusive Baryon Production in e+ e- Annihilation

Piccolo, M. ; Peruzzi, I. ; Luke, D. ; et al.
Phys.Rev.Lett. 39 (1977) 1503, 1977.
Inspire Record 121395 DOI 10.17182/hepdata.20965

The inclusive production of antiprotons and Λ's in e+e− annihilation has been measured as a function of the c.m. energy in the range 3.7-7.6 GeV. We find that the baryon cross section has a behavior different from the total hadronic production. Our results show a rapid rise in the ratio σp¯σμμ between 4.4 and 5 GeV, consistent with what would be expected from charmed baryon production. Λ¯ production is 10-15% of p¯ production at all energies.

1 data table
Table 1

NOT INCLUDING SYSTEMATIC ERRORS.


Inclusive eta Production at Large Transverse Momenta

Donaldson, G.J. ; Gordon, H.A. ; Lai, K.-W. ; et al.
Phys.Rev.Lett. 40 (1978) 684, 1978.
Inspire Record 122477 DOI 10.17182/hepdata.20917

We have measured the ratio of inclusive production of η to π0 at transverse momenta above 1.5 GeV/c. Results are presented for various meson and proton beams with momenta of 100, 200, and 300 GeV/c incident upon a hydrogen target. The ηπ0 production ratio is found to be independent of incident beam momentum and of the transverse and longitudinal momenta of production. The ratio for pion- and proton-induced reactions is 0.44 ± 0.05; for kaons, it is 0.74 ± 0.12.

11 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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rivet Analysis
Inclusive Production of $D$ Mesons in $e^+ e^-$ Annihilation at 7-{GeV}

Rapidis, P.A. ; Feldman, G.J. ; Abrams, G.S. ; et al.
Phys.Lett.B 84 (1979) 507-510, 1979.
Inspire Record 133123 DOI 10.17182/hepdata.27331

Inclusive momentum and energy spectra of neutral and charged D-mesons produced in e + e − annihilation at energies near 7 GeV are presented. The slope of the energy spectrum is similar to the charged pion spectrum at the same energy. The inclusive cross section σ(e + e − → D or D + anything) at 7 GeV is 4.8±1.3 nb.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

SCALING VARIABLE IS X(P=3,DEF=2*E(P=3)/SQRT(S)) > 0.54.

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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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