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Production of charmonium states in pi- Be collisions at 515-GeV/c

The E672-E706 collaboration Koreshev, V. ; Jesik, R. ; Mendez, H. ; et al.

Phys.Rev.Lett. 77 (1996) 4294-4297, 1996.

Inspire Record 419626 DOI 10.17182/hepdata.42234

We report on χc1 and χc2 production in the Feynman-x range 0.1<xF<0.8 in 515GeV/c π−Be collisions. The χc states are observed via their radiative decays into J/ψ's. The resulting photons are detected either as showers in the electromagnetic calorimeter or after conversion in the target as e+e− pairs in the tracking system. The fraction of J/ψ production due to χc1 and χc2 decays is 0.443±0.041±0.035. The ratio of the χc1 to χc2 cross section is 0.57±0.18±0.06. Our results on J/ψ, ψ(2S), and χc production indicate that 0.454±0.044±0.042 of J/ψ's are produced directly.

3 data tables

Table 1

No description provided.

Table 2

Cross section for the direct J/PSI production.

Table 3

No description provided.

Production of J / psi and psi (2S) mesons in pi- Be collisions at 515-GeV/c

The E672 & E706 collaborations Gribushin, A. ; Abramov, V. ; Antipov, Yu. ; et al.

Phys.Rev.D 53 (1996) 4723-4733, 1996.

Inspire Record 401108 DOI 10.17182/hepdata.42344

We have studied the production of J/ψ and ψ(2S) charmonium mesons in 515 GeV/c π−Be collisions in the Feynman-x range 0.1<xF<0.8. J/ψ mesons were detected via their decay into μ+μ−, and ψ(2S) mesons were studied in both the μ+μ− and J/ψπ+π− decay modes. J/ψ differential cross sections have been measured as functions of xF,pT2, and the cosine of the Gottfried-Jackson decay angle. We measure an inclusive J/ψ cross section of B(J/ψ→μ+μ−)σ(π−Be→J/ψ+X)/A= [9.3±0.1(stat)±1.1(syst)] nb/nucleon for J/ψ xF≳0.1. Our results are compared with those from other experiments performed at lower beam energies. We also measure the differential ψ(2S) cross section as a function of both xF and pT2, and a ψ(2S) inclusive cross section of B(ψ(2S)→J/ψπ+π−)σ(π−Be→ψ(2S)+X)/A=[7. 4±1.5(stat)±1.2(syst)] nb/nucleon for ψ(2S) xF≳0.1. The fraction of the inclusive J/ψ yield due to ψ(2S) meson decays is 0.083±0.017(stat) ±0.013(syst), and the observed ratio of ψ(2S) decay rates is B(ψ(2S)→J/ψπ+π−)/B(ψ(2S)→μ+μ−) =30.2±7.2(stat)±6.8(syst). We have searched for production of ‘‘hidden’’ charm resonances decaying into either J/ψπ±,ψ(2S)π±, or J/ψπ+π− systems, and report an upper limit of 3.1 nb/nucleon for the product of branching ratio and cross section for the recently reported enhancement at a J/ψπ+π− mass of 3.836 GeV/c2. © 1996 The American Physical Society.

7 data tables

Table 1

Statistical errors only. Normalization uncertainty is 12%.

Table 2

Statistical errors only. Normalization uncertainty is 12%.

Table 3

Statistical errors only. Normalization uncertainty is 12%.. Theta is the angle between the MU+ and the beam axis in the J/PSI restframe (Gottfried-Jackson decay angle).

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Bottom production in pi- - Be collisions at 515-GeV/c

The E672/E706 collaboration Jesik, R. ; Abramov, V. ; Antipov, Yu. ; et al.

Phys.Rev.Lett. 74 (1995) 495-498, 1995.

Inspire Record 374151 DOI 10.17182/hepdata.42447

We report on a sample of Jψ mesons coming from secondary vertices, a characteristic of heavyquark decay, detected in the Fermilab Meson West spectrometer. Based on eight signal events in which a Jψ emerges from a secondary vertex occurring in an air-gap region, we obtain an inclusive bb¯ cross section of 75 ± 31 ± 26 nb/nucleon. This result is compared to recent QCD predictions. We have also observed several events in the exclusive decay modes B±→Jψ+K± and B0→Jψ+K0* in which the B mass is fully reconstructed.

2 data tables

Table 1

The cross section is multiplied on Br(J/PSI --> MU+ MU-).

Table 2

No description provided.

The Production of J/psi and Associated Particles in the Collision of 530-GeV/c Protons and Pions with Nuclear Targets

De, K. ; Crittenden, R. ; Dzierba, A. ; et al.

(1989) 467-472, 1989.

Inspire Record 280605 DOI 10.17182/hepdata.22998

None

3 data tables

Table 1

Interacting beam cross-section.

Table 2

No description provided.

Table 3

No description provided.

Properties of $J / \psi$ Production in $\pi^-$ Be and p Be Collisions at 530 GeV/c

The E672/706 collaboration Abramov, V. ; Antipov, Yu. ; Baldin, B. ; et al.

FERMILAB-PUB-91-062-E, 1991.

Inspire Record 315071 DOI 10.17182/hepdata.42566

None

2 data tables

Table 1

Data is extrapolated to full x range.

Table 2

Data requested from authors.

Analysis of the Reaction K- p --> K- pi- pi+ p at 40-GeV/c

The CERN-Serpukhov Boson Spectrometer Group collaboration Antipov, Yu.M. ; Ascoli, G. ; Busnello, R. ; et al.

Nucl.Phys.B 86 (1975) 381-402, 1975.

Inspire Record 90643 DOI 10.17182/hepdata.32087

The reaction K − p → K − π − π + p has been measured at 25 and 40 GeV/ c at the Serpukhov Proton Accelerator. The production cross section at 25 and 40 GeV/ c as a function of momentum transfer and K ππ mass is presented, and results of the partial-wave analysis of the K ππ system yielding information about Q(1300), K ∗ (1400) and L(1770) mesons are discussed.

3 data tables

Table 1

No description provided.

Table 2

K** DEFINED BY 1.30 < M(K PI PI) < 1.54 GEV.

Table 3

L IS DEFINED AS THE 2- STATE WITH 1.6 < M(K PI PI) < 1.9 GEV.

Boson States in the Reaction pi- p --> pi- pi- pi+ p with Leading pi+ Meson at 25-GeV/c

The Serpukhov-CERN collaboration Antipov, Yu.M. ; Busnello, R. ; Damgaard, G. ; et al.

Nucl.Phys.B 119 (1977) 45-59, 1977.

Inspire Record 109772 DOI 10.17182/hepdata.35516

The reaction π − + p → π − + π − + π + + p at 25 GeV/ c was studied in the mass region M 3 π ⩾ 1.8 GeV with leading π + . The mass spectrum of the π + π − system shows peaks corresponding to the ϱ 0 , f and g 0 resonances and an enhancement around 1.9 GeV. Evidence is presented for a J P = 3 + s-wave g 0 π − state (A 4 ) similar to the ϱ 0 π − (A 1 ) and fπ − (A 3 ) threshold enhancements.

1 data table

Table 1

No description provided.