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J / psi and psi-prime production at the CERN p anti-p collider

The UA1 collaboration Albajar, C. ; Albrow, M.G. ; Allkofer, O.C. ; et al.

Phys.Lett.B 256 (1991) 112-120, 1991.

Inspire Record 300862 DOI 10.17182/hepdata.26999

We have measured the production cross-section times branching ratio for J/ψ→μ + μ − in pp̄ interactions at √ s = 630 GeV in the kinematic range |y|<2.0 and p T >5 GeV /c, BR ( J /ψ→μ + μ − )σ( p p ̄ → J /ψ)=6.18±0.24±0.81 nb . The data sample collected in 1988 and 1989 for an integrated luminosity of 4.7 pb −1 represents a fivefold improvement over the statistics in our earlier study of the J / ψ production process, and the p T distribution which is measured extends to 28 GeV / c . Using event topology we show that the rate for the direct production of J / ψ , via radiative decays of χ states, is larger than that for production via B-hadrons. Production of ψ′ is also studied using the decay modes < ψ ′→ μ + μ − and ψ ′→ J / ψπ + ψ − .

4 data tables

Table 1

Numerical values supplied by Nick Ellis.

Table 2

Table 3

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Experimental study of the annihilation of anti-protons at rest in nuclear photoemulsion and the optical cascade approach

Batusov, Yu.A. ; Bunyatov, S.A. ; Falomkin, I.V. ; et al.

JINR-E1-90-486, 1990.

Inspire Record 303148 DOI 10.17182/hepdata.39437

None

1 data table

Table 1

ANTIPROTONS STOPPING IN THE PHOTOEMULSION.

Inclusive D*+- production in photon-photon collisions

The TPC/Two-Gamma collaboration Alston-Garnjost, M. ; Avery, R.E. ; Barker, A.R. ; et al.

Phys.Lett.B 252 (1990) 499-504, 1990.

Inspire Record 299662 DOI 10.17182/hepdata.29510

The TPC/Two-Gamma Collaboration has measured the inclusive cross section for production of charmed D ∗± mesons in photon-photon collisions. The reaction utilized was e + e - →e + e - D ∗± X, with D ∗± →D O π +- , D O →K -+ π ± , and either zero or one outgoing e ± detected. The result, σ(e + e - → e + e - D ∗± X) = 74±26±19 pb , is in agreement with the quark parton mo del prediction for e + e - → e + e - c c , combined with a Lund model for the hadronization of the charmed quarks.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

Beauty production at the CERN p anti-p collider

The UA1 collaboration Albajar, C. ; Albrow, M.G. ; Allkofer, O.C. ; et al.

Phys.Lett.B 256 (1991) 121-128, 1991.

Inspire Record 302583 DOI 10.17182/hepdata.48531

We report measurements of b-quark and B-hadron production in pp̄ collisions at √ s =630 GeV. We use muon samples to extract beauty production cross-sections over a wide range of transverse momentum in the central rapidity range | y | < 1.5. We compare our results to an O(α s 3 ) QCD prediction and find good agreement over the measured b-quark transverse momentum range 6 GeV / c to 54 GeV / c . Using the shape of the p T and y distribution predicted by QCD to extrapolate our data, we infer a total cross-section for b-quark production at √s=630 GeV of σ( p p ̄ → b b ̄ + X )=19.3±7( exp. )±9( th. μ b .

10 data tables

Table 1

No description provided.

Table 2

The cross section is multipled on the B(J/PSI --> MU+ MU-).

Table 3

No description provided.

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A Study of the recombination scheme dependence of jet production rates and of alpha-s (m(Z0)) in hadronic Z0 decays

The OPAL collaboration Akrawy, M.Z. ; Alexander, G. ; Allison, John ; et al.

Z.Phys.C 49 (1991) 375-384, 1991.

Inspire Record 299833 DOI 10.17182/hepdata.15085

The error includes the experimental uncertainties (±0.003), uncertainties of hadronisation corrections and of the degree of parton virtualities to which the data are corrected, as well as the uncertainty of choosing the renormalisation scale.

9 data tables

Table 1

Jet production rates using the E0 recombination scheme.

Table 2

Jet production rates using the E recombination scheme.

Table 3

Jet production rates using the p0 recombination scheme.

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Photoproduction of D Mesons

The E-687 collaboration Buchholz, D. ; Frabetti, P.L. ; Bogart, C.W. ; et al.

FERMILAB-FN-0555, 1990.

Inspire Record 300996 DOI 10.17182/hepdata.43002

Preliminary results are presented using the Wide Band photon beam at Fermilab to measure the cross-section of $D^{*\pm}$ and $D^{\pm}$ photoproduction on a Be target over the photon energy range from 100 GeV to 350 GeV....

3 data tables

Table 1

INCLUDES THE FOLLOWING DECAYS: D*(2010)+- --> D0 PI+-, D0 --> K- PI+.

Table 2

INCLUDES THE FOLLOWING DECAYS: D*(2010)+- --> D0 PI+-, D0 --> K- PI+, D0 --> K- 2PI+ PI-.

Table 3

INCLUDES THE DECAYS: D+ --> K- 2PI+.

A Measurement of sigma B (W ---> e neutrino) and sigma B (Z0 ---> e+ e-) in anti-p p collisions at s**(1/2) = 1800-GeV

The CDF collaboration Abe, F. ; Amidei, D. ; Apollinari, G. ; et al.

Phys.Rev.D 44 (1991) 29-52, 1991.

Inspire Record 302820 DOI 10.17182/hepdata.42696

An analysis of high-transverse-momentum electrons using data from the Collider Detector at Fermilab (CDF) of p¯p collisions at s=1800 GeV yields values of the production cross section times branching ratio for W and Z0 bosons of σ(p¯p→WX→eνX)=2.19±0.04(stat)±0.21(syst) nb and σ(p¯p→Z0X→e+e−X)=0.209±0.013(stat)±0.017(syst) nb. Detailed descriptions of the CDF electron identification, background, efficiency, and acceptance are included. Theoretical predictions of the cross sections that include a mass for the top quark larger than the W mass, current values of the W and Z0 masses, and higher-order QCD corrections are in good agreement with these measured values.

1 data table

Table 1

No description provided.

The (pi+, K+) reaction on C-12 and Fe-56

Akel, M. ; Amann, J.F. ; Chiba, J. ; et al.

Nucl.Phys.A 534 (1991) 478-492, 1991.

Inspire Record 300837 DOI 10.17182/hepdata.36713

None

2 data tables

Table 1

Axis error includes +- 0.0/0.0 contribution (?////).

Table 2

Axis error includes +- 0.0/0.0 contribution (?////).

Study of the reaction anti-p p ---> anti-Lambda Lambda at 1.546-GeV/c and 1.695-GeV/c

Barnes, P.D. ; Diebold, G. ; Franklin, G. ; et al.

Nucl.Phys.A 526 (1991) 575-601, 1991.

Inspire Record 301648 DOI 10.17182/hepdata.36756

The PS185 experiment at the CERN Low Energy Antiproton Ring (LEAR) has studied the reaction p ̄ p → \ ̄ gLΛ at several momenta. In this paper results from two runs with high statistics at 1.546 GeV/ c and 1.695 GeV/ c are described. Based on 4063 and 11362 analysed events, respectively, differential and integrated cross sections, polarizations and spin correlations are presented. The singlet fraction, extracted from the spin correlations, is consistent with zero at both momenta, showing that the \ ̄ gLΛ pairs are produced in a pure triplet state. A comparison of the decay asymmetry parameters of Λ and \ ̄ gL reduces the upper limits for the violation of the CP invariance for this system.

10 data tables

Table 1

No description provided.

Table 2

THE BESTFIT WITH LMAX=3, HI2=1.204.

Table 3

THE BESTFIT WITH LMAX=6, HI2=0.547.