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Production of upsilon(1S) mesons from chi(b) decays in p anti-p collisions at S**(1/2) = 1.8-TeV

The CDF collaboration Affolder, T. ; Akimoto, H. ; Akopian, A. ; et al.

Phys.Rev.Lett. 84 (2000) 2094-2099, 2000.

Inspire Record 508395 DOI 10.17182/hepdata.50106

We have reconstructed the radiative decays $\chi_{b}(1P) \to \Upsilon(1S) \gamma $ and $\chi_{b}(2P) \to \Upsilon(1S) \gamma $ in $p \bar{p}$ collisions at $\sqrt{s} = 1.8$ TeV, and measured the fraction of $\Upsilon(1S)$ mesons that originate from these decays. For $\Upsilon(1S)$ mesons with $p^{\Upsilon}_{T}>8.0$ GeV/$c$, the fractions that come from $\chi_{b}(1P)$ and $\chi_{b}(2P)$ decays are $(27.1\pm6.9(stat)\pm4.4(sys))%$ and $(10.5\pm4.4(stat)\pm1.4(sys))%$, respectively. We have derived the fraction of directly produced $\Upsilon(1S)$ mesons to be $(50.9\pm8.2(stat)\pm9.0(sys))%$.

1 data table

Table 1

No description provided.

AZIMUTHAL ASYMMETRY OF NEGATIVELY CHARGED HADRONS IN THE REACTION ANTI-NEUTRINO N ---> MU+ H- X

Ammosov, V.V. ; Asratian, A.E. ; Berge, J.P. ; et al.

JETP Lett. 38 (1983) 248-251, 1983.

Inspire Record 202188 DOI 10.17182/hepdata.69924

None

2 data tables

Table 1

No description provided.

Table 2

No description provided.

TOTAL ANTI-NEUTRINOS NUCLEON CHARGED CURRENT CROSS-SECTION IN THE ENERGY RANGE 10-GEV - 50-GEV

Asratian, A.E. ; Efremenko, V.I. ; Fedotov, A.V. ; et al.

Phys.Lett.B 137 (1984) 122-124, 1984.

Inspire Record 203433 DOI 10.17182/hepdata.30593

The total v μ N charged current cross section in the energy interval 10–50 GeV is unfolded from 15' bubble chamber antineutrino data. The method is to isolate the quasielastic events and determine their relative contribution to the overall charged current sample. The scale parameter is found to be (0.29 ± 0.03) × 10 −38 cm 2 GeV −1 . Relevance of the method for neutrino oscillation studies is discussed.

3 data tables

Table 1

Measured charged current total cross section.

Table 2

Measured charged current total cross section.

Table 3

Measured charged current total cross section.

Study of Sigma+- (1385) Inclusive Production in K- p Interactions at 4.2-GeV/c

The Amsterdam-CERN-Nijmegen-Oxford collaboration Barreiro, F. ; Berge, J.P. ; Ganguli, S.N. ; et al.

Nucl.Phys.B 126 (1977) 319-339, 1977.

Inspire Record 111752 DOI 10.17182/hepdata.35325

Properties of Σ ± (1385) inclusively produced in 4.2 GeV/ c K − p interactions are studied. Inclusive cross sections are presented together with differential cross sections as functions of x and p t 2 for both Σ + (1385) and Σ − (1385). The complete density matrix for Σ + (1385) production at small momentum transfer is studied as a function of t and of recoil mass MM 2 . Substantial agreement with the predictions of the additive quark model is found. The Σ + (1385) production in the target fragmentation region is studied in the framework of the triple-Regge model.

3 data tables

Table 1

Axis error includes +- 5/5 contribution (ERROR OF NORMALIZATION).

Table 2

Axis error includes +- 5/5 contribution (ERROR OF NORMALIZATION).

Table 3

Axis error includes +- 5/5 contribution (ERROR OF NORMALIZATION).

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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A Study of Inclusive xi- Production from K- p Interaction at 4.2-GeV/c

The Amsterdam-CERN-Nijmegen-Oxford collaboration Ganguli, S.N. ; Berge, J.P. ; Gavillet, P. ; et al.

Nucl.Phys.B 128 (1977) 408-420, 1977.

Inspire Record 111753 DOI 10.17182/hepdata.36076

A study of inclusive Ξ − production from a high statistics K − p experiment at 4.2 GeV/ c has been made. The total Ξ − production cross section is 157 ± 8 μ b. Approximately 15% of the Ξ − arise from decay of the Ξ ∗0 (1530) resonance. The polarization of the Ξ − is found to be negative and is nearly equal in value to that of the Λ 0 from the inclusive reaction K − + p → Λ 0 + anything. An analysis of the inclusive production of Ξ − has been made in the framework of the triple-Reege formalism.

2 data tables

Table 1

No description provided.

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.

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.

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.