Nilsson, S.
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AN AMPLITUDE ANALYSIS OF THE K+ K- SYSTEM PRODUCED IN THE REACTION PI- P ---> K+ K- N AT 10-GEV/C

The BARI-BONN-CERN-GLASGOW-LIVERPOOL-MILAN-VIENNA collaboration Costa, G. ; Donald, R.A. ; Edwards, D.N. ; et al.
Nucl.Phys.B 175 (1980) 402-434, 1980.
Inspire Record 159739 DOI 10.17182/hepdata.34458

We present results on an amplitude analysis of the K + K − system produced in the reaction π − p→K + K − n from threshold up to 2.2 GeV. The branching ratios of f 0 and f' to K K have been determined. In the low mass region of the K K system the observation of an S-wave enhancement at 1.3 GeV and the interference of the f 0 -A 2 -f' mesons are studied. We observe a 3 − structure in the mass region of 1.7 GeV which is consistent with g 0 production. With this interpretation the branching ratio g→ K K has been determined. Evidence for a new structure in the J p = 2 + wave around 1.8 GeV with a width of ∼200 MeV is presented.

2 data tables
Table 1

HELICITY ZERO D-WAVE AMPLITUDE FITTED BY SUM OF BREIT-WIGNER RESONANCES. F 14 GIVES T-DEPENDENCE. ALSO EVIDENCE FOR 1.8 GEV STATE WITH 0.60 +- 0.13 MUB PRODUCTION CROSS SECTION.

Table 2

FROM HELICITY ZERO F-WAVE AMPLITUDE ASSUMING PREDOMINANTLY G(1680)0 PRODUCTION. F 16 GIVES T-DEPENDENCE.


Observation and Quantum Numbers Determination of the E(1420) Meson in pi- p Interactions at 3.95-GeV/c

The CERN-College de France-Madrid-Stockholm collaboration Dionisi, C. ; Gavillet, P. ; Armenteros, R. ; et al.
Nucl.Phys.B 169 (1980) 1-19, 1980.
Inspire Record 152746 DOI 10.17182/hepdata.34515

In a high statistics (90 events/μb) bubble chamber experiment, the reactions π − p→K s 0 K ± π ∓ n have been studied at 3.95 GeV/ c . A significant enhancement is observed in the ( K K π) system which we attribute to the production of the E(1420) meson. For its mass, M , and width, Λ, we find M =1426±6 MeV and Γ =40±15 MeV. The E(1420) quantum numbers are determined to be I G J P =0 + 1 + with a branching ratio E → K ∗ K + c.c E →[δπ+( K ∗ K + c.c. )]=0.86±0.12 , where δ→ K K . The cross section for the reaction π − p→En, with E→K 0 K ± π ± , is 8.2±1.0 μ b. Forward and backward productions are observed in the approximate ratio 2:1. The SU(3) assignment of the E(1420) meson is discussed.

3 data tables
Table 1

BACKGROUND SUBTRACTED.

Table 2

No description provided.

Table 3

No description provided.


K*0 (890) POLARIZATION MEASUREMENTS IN THE HYPERCHARGE EXCHANGE REACTION PI- P ---> K*0 (890) LAMBDA0 / SIGMA0 AT 10-GEV/C

The BARI-BONN-CERN-DARESBURY-GLASGOW-LIVERPOOL-MILAN-VIENNA collaboration Evangelista, C. ; Ghidini, B. ; Palano, A. ; et al.
Nucl.Phys.B 165 (1980) 383-394, 1980.
Inspire Record 157497 DOI 10.17182/hepdata.34585

K ∗0 (890) production in the hyperchange exchange reaction π − p → K ∗0 (890) Λ 0 Σ 0 at 10 GeV/ c (28 448 events) is discussed. An amplitude analysis in the t ′ range up to 1 GeV 2 shows that the production mechanism is dominated by natural parity exchange (∼84%). Comparisons are made with predictions from a Regge model and a quark model.

2 data tables
Table 1

DENSITY MATRIX ELEMENTS IN THE GOTTFRIED-JACKSON SYSTEM ALLOWING FOR COHERENT S-WAVE BACKGROUND TO P-WAVE BREIT-WIGNER K*(892)0 RESONANCE.

Table 2

No description provided.


Characteristics of J/$\psi$ and $\Upsilon$ production at the {CERN} intersecting storage rings

Kourkoumelis, C. ; Resvanis, L. ; Filippas, T.A. ; et al.
Phys.Lett.B 91 (1980) 481-486, 1980.
Inspire Record 152744 DOI 10.17182/hepdata.27235

We present the B( d θ d y ) y=0 for J /ψ over thefull range of ISR energies and for ϒ at √ s = 53 and 63 GeV, using their dielectron decay mode. The average transverse momentum and the decay angles are presented. We found ( p T ) = 1.75 ± 0.19 GeV for ϒ, being higher than ( p T ) of the continuum and rising with √s. We present a comparison of the cross sections of J/ψ and ϒ with those of the continuum, at the same masses, as a function of √s. An appropriate scaling of the hadronic production of quark-antiquark narrow bound states involving ⋉, J/ψ, ψ′, ϒ, and ϒ′ is presented as a function of m /√ s at y = 0, and is compared with Drell-Yan scaling.

2 data tables
Table 1

No description provided.

Table 2

UPSILON HERE = UPSILON+UPSILON PRIME.


Study of Massive Electron Pair Production at the {CERN} Intersecting Storage Rings

Kourkoumelis, C. ; Resvanis, L.K. ; Filippas, T.A. ; et al.
Phys.Lett.B 91 (1980) 475-480, 1980.
Inspire Record 152742 DOI 10.17182/hepdata.27237

Data from a study of electron pairs produced in pp collisions (√ s = 5 and 63 GeV) are used to extend measurements of the scaling function down to m /√ s ≈ 0.07 (4.5 < m < 19 GeV). The dilepton continuum can be described by the scaling formula (fx475-1)

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Observation of the $\rho^-$prime (1600) in the Channel $\gamma p \to \pi^+ \pi^- p$

The Bonn-CERN-Ecole Poly-Glasgow-Lancaster-Manchester-Orsay-Paris-Rutherford-Sheffield collaboration Aston, D. ; Atkinson, M. ; Bailey, R. ; et al.
Phys.Lett.B 92 (1980) 215-218, 1980.
Inspire Record 152747 DOI 10.17182/hepdata.27241

A dipion enhancement of mass 1.59 GeV and width 0.23 GeV is observed in the channel γp→π + π − p. The spin-parity of the enhancement is consistent with being 1 − .

1 data table
Table 1

No description provided.


rivet Analysis
Search for Narrow Resonances in $e^+ e^-$ Annihilation at {PETRA}

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Phys.Lett.B 91 (1980) 148-151, 1980.
Inspire Record 152291 DOI 10.17182/hepdata.27236

We have performed a search for narrow resonances in the center of mass energy range from 29.90 to 31.46 GeV using the e + e − storage ring PETRA at DESY. We present the total cross section for hadron production and an upper limit for resonance production, indicating that no bound state of charge- 2 3 quarks exists in this energy range.

2 data tables
Table 1

AVERAGE VALUE OF R OVER THE SCAN REGION.

Table 2

THESE MEASUREMENTS COMBINED WITH PREVIOUS DATA AT 30.0 AND 31.6 GEV REPORTED IN CH. BERGER ET AL., PL 86B, 413 (1979).


Search for Narrow Resonances in $e^+ e^-$ Annihilation at c.m. Energies Between 29.90-{GeV} and 31.46-{GeV}

The JADE collaboration Bartel, W. ; Cords, D. ; Dittmann, P. ; et al.
Phys.Lett.B 91 (1980) 152-154, 1980.
Inspire Record 152290 DOI 10.17182/hepdata.27258

A search for narrow resonances in e + e − annihilation at c.m. energies between 29.90 and 31.46 GeV provides no evidence for the existence of such states. The 90% confidence upper limit on the integrated resonance cross section is 38 nb MeV, significantly below the value expected for the lowest (t,t̄) bound state.

1 data table
Table 1

No description provided.


STUDY OF (PI+ PI- PI+ PI-) AND (PI+ PI- PI0) CHANNEL IN E+ E- ANNIHILATION AT 1.450-GEV - 1.875-GEV center-of-mass ENERGY

Esposito, B. ; Marini, A. ; Ronga, F. ; et al.
Lett.Nuovo Cim. 28 (1980) 195-200, 1980.
Inspire Record 158282 DOI 10.17182/hepdata.37366

None

2 data tables
Table 1

No description provided.

Table 2

POSSIBLE EVIDENCE FOR OMEGA(1670) RESONANCE.


MEASUREMENTS OF THE EM TIMELIKE FORM-FACTORS FOR KAON AND PION AT S**(1/2) = 1.5-GEV

Esposito, B. ; Marini, A. ; Piano Mortari, Giovanni ; et al.
Lett.Nuovo Cim. 28 (1980) 337-342, 1980.
Inspire Record 158283 DOI 10.17182/hepdata.37369

None

1 data table
Table 1

No description provided.