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Production of Sigma (1660) in K- p Interactions at 4.2-GeV/c

The Amsterdam-CERN-Nijmegen-Oxford collaboration Timmermans, Jan ; Engelen, J.J. ; Heinen, P.M. ; et al.
Nucl.Phys.B 112 (1976) 77-106, 1976.
Inspire Record 108671 DOI 10.17182/hepdata.35709

The reaction of K − p → Σ + (1660) π − was studied in a 65 event/μb sample of Σππ(π), Λππ(π) and p K 0 π − final states. The main production features observed are that the Σ (1660) decaying into Σππ is mostly Λ (1405) π and is produced only at small t ; the Σ (1660) decaying into Σπ shows both forward and backward production. This confirms earlier results suggesting the existence of two Σ (1660) resonances. An Adair analysis and a (model-dependent) moments analysis find a J = 3 2 preference for the Σ + (1660)→ Λ (1405) π + → Σ + π − π + ; a Dalitz-Miller analysis of the decay Σ + (1660) → Λ (1405) π + → Σ − π + π + determines J P to be 3 2 − . For the Σ + (1660) → Σ 0 π + a moments analysis suggests J = 3 2 . Branching ratios are determined, which (with the exceptation of the Λ (1405) π mode) are in reasonable agreement with results from formation experiments for the J P = 3 2 − Σ(1660) resonance. We compare our branching ratios with SU(3) and SU(6) predictions; the latter comparison suggests that, unless there is strong configuration mixing, Σ (1660) → Λ (1405) π , if 3 2 − , cannot be a member of the (70, 1 − ) multiplet.

4 data tables
Table 1

No description provided.

Table 2

PRODUCTION ANGULAR DISTRIBUTIONS OF SIG(1670D13)+ DIFFER FOR THE TWO FINAL STATES <LAM(1405S01) PI+> AND <SIGMA PION> SUGGESTING THE EXISTENCE OF TWO SIG(1660) RESONANCES.

Table 3

VALUES IN STRONG DISAGREEMENT WITH THE STODOLSKY-SAKURAI MODEL PREDICTIONS.

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Study of Hypercharge Exchange Reactions of the Type K- p --> 1- 3/2+- at 4.2-GeV/c

The Amsterdam-CERN-Nijmegen-Oxford collaboration Aguilar-Benitez, M. ; Barreiro, F. ; Hemingway, R.J. ; et al.
Nucl.Phys.B 124 (1977) 189-228, 1977.
Inspire Record 101289 DOI 10.17182/hepdata.50024

Results are presented for the quasi two-body hypercharge exchange reactions of the type using data from a high statistics bubble chamber experiment. Total and differential cross sections and the momentum transfer dependence of the meson and hyperon resonance single density matrix elements are discussed. Amplitude analyses are performed for the first two reactions. The results are compared with quark model and duality predictions and with those from other related reactions.

20 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Production and Decay of xi* (1820) in K- p Reactions at 4.2-GeV/c

The Amsterdam-CERN-Nijmegen-Oxford collaboration Gay, J.B. ; Armenteros, R. ; Berge, J.P. ; et al.
Phys.Lett.B 62 (1976) 477-480, 1976.
Inspire Record 108822 DOI 10.17182/hepdata.27651

Using a high statistics sample of K − p interactions at 4.2 GeV/ c , the production and decay properties of the Ξ ∗ (1820) are discussed. The mass and width are found to be M = (1823 ± 2) MeV and Γ = (21 ± 7) MeV. Evidence is found for Ξ ∗ (2030) in the Σ K ̄ channel and for a new Ξ ∗ at a mass of 2120 MeV in the ΛK − channel.

2 data tables
Table 1

XI(1820)- PRODUCTION CROSS SECTIONS ARE FOR -UP < 3 GEV**2 AND ARE CORRECTED FOR ISOSPIN AND UNSEEN DECAY MODES.

Table 2

No description provided.


Backward Production of a Spin Parity 1+ rho pi Enhancement at 1.04-GeV

The Amsterdam-CERN-Nijmegen-Oxford collaboration Gavillet, P. ; Berge, J.P. ; Ferrando, A. ; et al.
Phys.Lett.B 69 (1977) 119, 1977.
Inspire Record 120469 DOI 10.17182/hepdata.27551

A spin-parity 1 + ϱπ enhancement is observed for the 3π mass spectrum in the reaction K − p → Σ − π + π + π − where events with a small (K − → Σ − ) momentum transfer are selected. The mass (1040 MeV) and width (230 MeV) of this enhancement are reminiscent of the A 1 → ϱπ bump which has mainly been observed in the diffractive-like processes. The cross section for this enhancement at 4.15 GeV/ c incident K − momentum is (3.6 ± 0.5) μ b.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


The Reactions K- p --> Lambda pi0, Lambda eta, Lambda eta' at 4.2-GeV/c

The Amsterdam-CERN-Nijmegen-Oxford collaboration Marzano, F. ; Hemingway, R.J. ; Loverre, P.F. ; et al.
Nucl.Phys.B 123 (1977) 203-222, 1977.
Inspire Record 119257 DOI 10.17182/hepdata.35450

In a high statistics CERN 2 m bubble chamber experiment the differential cross sections and polarizations of the Λ for the reactions K − p → Λπ 0 , Λη , Λη ′ at 4.2 GeV/ c have been measured. The reaction K − p → Λη exhibits a pronounced dip around − t ∼0.5 ( GeV / c ) 2 and all three reactions show a significant backward peaking (− u < 1.0 (GeV/ c ) 2 ). The Λ polarization in the reaction K − p → Λπ 0 is measured to be significantly different from zero throughout most of the available t -range. Forward cross sections enable a determination of R T , the ratio of singlet/octet coupling η 1 KK ∗∗ η 8 KK ∗∗ . Backward cross sections are utilized to estimate the effective η-nucleon coupling constant g η NN 2 over the − u range 0–1.5 ( GeV /c) 2 .

15 data tables
Table 1

QUOTED VALUES OF THE KINEMATIC LOWER LIMITS OF -T AND -U.

Table 2

Axis error includes +- 5/5 contribution.

Table 3

Axis error includes +- 5/5 contribution.

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The K- p Charge Exchange and Elastic Scattering Reactions at 4.2-GeV/c

The Amsterdam-CERN-Nijmegen-Oxford collaboration Marzano, F. ; Toet, D.Z. ; Gavillet, P. ; et al.
Phys.Lett.B 68 (1977) 292, 1977.
Inspire Record 119361 DOI 10.17182/hepdata.48927

In this letter results are presented on the reactions K − p → K 0 n and K − p → K − p from a high statistics CERN 2-metre hydrogen bubble chamber exposure at 4.15 GeV/ c . The behaviour of the differential cross section as a function of four-momentum transfer shows remarkable similarities between the two reactions studied. From a comparison of our data with K + p elastic scattering at 4.27 GeV/ c we draw some conclusions concerning the magnitude of the contributing amplitudes.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Xi* (2030) Production in K- p Reactions at 4.2-GeV/c

The Amsterdam-CERN-Nijmegen-Oxford collaboration Hemingway, R.J. ; Armenteros, R. ; Berge, J.P. ; et al.
Phys.Lett.B 68 (1977) 197, 1977.
Inspire Record 119852 DOI 10.17182/hepdata.27567

Significant production of (2030) is observed in the channel K − p → (Σ K − K + from a high statistics bubble chamber exposure at 4.2 GeV/ c . The mass and width are determined to be 2024 ± 2 MeV and 16 ± 5 MeV respectively. Apart from Σ K , the only other decay channel is found to be Λ K .

1 data table
Table 1

ASSUMING XI(2030) HAS ISOSPIN HALF, CROSS SECTIONS CORRECTED FOR UNOBSERVED NEUTRAL DECAYS.


Observation of the B Meson in K- p Interactions at 4.2-GeV/c

The Amsterdam-CERN-Nijmegen-Oxford collaboration Flatte, Stanley M. ; Gay, J.B. ; Hemingway, R.J. ; et al.
Phys.Lett.B 64 (1976) 225-229, 1976.
Inspire Record 109851 DOI 10.17182/hepdata.27607

A πω enhancement at 1245 MeV is observed in the reaction K − p → Σ + π − ω. Its properties agree with those of a B meson produced by natural-parity exchange thus establishing a coupling of the B to a K K ∗ system.

2 data tables
Table 1

No description provided.

Table 2

THE DATA FOR B+ PRODUCTION ARE QUOTED FROM CHUNG ET AL., PR D11, 2426 (1975) USING THE SLAC 82 IN HBC. 1.08 < M(PI OMEGA) < 1.38 GEV.


The Reactions K- p --> pi-+ Sigma+- (1385) at 4.2-GeV/c

The Amsterdam-CERN-Nijmegen-Oxford collaboration Holmgren, S.O. ; Aguilar-Benitez, M. ; Barreiro, F. ; et al.
Nucl.Phys.B 119 (1977) 261-291, 1977.
Inspire Record 110408 DOI 10.17182/hepdata.35566

The reactions K − p→ π − Σ + (1385) and K − p→ π + Σ − (1385) are studied at 4.2 GeV c incident momentum using data from a high statistics bubble chamber experiment corresponding to ∼80 events/μb. The total and differential cross sections are presented. Amplitude analyses are performed and the complete Σ ± (1385) helicity spin density matrices are extracted. The results are compared with the predictions of the additive quark model and exchange degeneracy. A substantial cross section is observed for the reaction K − p→ π + Σ − (1385) in the forward direction, which implies exotic meson quantum numbers in the t -channel. One possible interpretation of this process provides an explanation for the small but significant violations of the additive quark model predictions observed in the reaction K − p→ π − Σ + (1385) at low four-momentum transfer. In the backward direction unnatural parity exchange is shown to give a larger contribution to K − p→ Σ − (1385) π + than natural parity exchange.

11 data tables
Table 1

Axis error includes +- 5/5 contribution.

Table 2

Axis error includes +- 5/5 contribution.

Table 3

Axis error includes +- 5/5 contribution.

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Production and Decay Properties of f-prime (1514) in K- p Interactions at 4.2-GeV/c

The Amsterdam-CERN-Nijmegen-Oxford collaboration Barreiro, F. ; Diaz, J. ; Gay, J.B. ; et al.
Nucl.Phys.B 121 (1977) 237-250, 1977.
Inspire Record 111490 DOI 10.17182/hepdata.35514

Results are presented for the hypercharge exchange reaction K − p→ f ′(1514) Λ at a beam momentum of 4.15 GeV/ c . Total and differential cross sections have been determined. The Λ polarization and the tensor meson density matrix elements are given as a function of t ′.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

ALL EVENTS WITH 1.46<M(KS KS)<1.60GEV.