Alekseev, G.D.
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Photo-production of psi(2S) mesons at HERA.

The H1 collaboration Adloff, C. ; Aid, S. ; Anderson, M. ; et al.
Phys.Lett.B 421 (1998) 385-394, 1998.
Inspire Record 451266 DOI 10.17182/hepdata.44434

Quasi-elastic (z >0.95) photo-production of psi' mesons has been observed at HERA for photon-proton centre-of-mass energies in the range 40 to 160 GeV. The psi' mesons were identified through their decays to l+l- and to J/psi pi+ pi-, where the J/psi subsequently decays to l+l-, the lepton l being either a muon or an electron. The cross-section for quasi-elastic photoproduction was measured to be [18.0 +- 2.8 (stat) +- 3.0(syst)] nb at a photon-proton centre-of-mass energy of 80 GeV. The ratio of the psi' to J/psi quasi-elastic cross-sections is 0.150 +- 0.027 (stat) +- 0.022 (syst).

9 data tables
Table 1

Overall value for photoproduction cross section combining the different decay modes and data sample.. 1994 and 1995 data.. The second systematic error is from the branching ratio uncertainties.

Table 2

Combined cross section from PSI(3685) --> J/PSI(1S) < E+ E- > PI+ PI- and PSI(3685) --> J/PSI(1S) < MU+ MU- > PI+ PI- modes using both the 1994 and 1995 data.. The second systematic error is from the branching ratio uncertainties.

Table 3

Cross section from PSI(3685) --> J/PSI(1S) < E+ E- > PI+ PI- mode.

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Search for promptly produced heavy quarkonium states in hadronic Z decays

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adye, T. ; et al.
Z.Phys.C 69 (1996) 575-584, 1996.
Inspire Record 401612 DOI 10.17182/hepdata.48135

A search has been made for direct production of heavy quarkonium states in more than 3 million hadronic Z0 decays in the 1991–1994 DELPHI data. Prompt J/ψ, ψ(2S) and Υ candidates have been searched for through their leptonic decay modes using criteria based on the kinematics and decay vertex positions. New upperlimits are set at the 90% confidence level for Br(Z0 → (QQ) X)/Br (Z0 → hadrons) for various strong production mechanisms of J/ψ and Υ these range down to 0.9 × 10−4. The limits are set in the presence of a small excess (∼ 1% statistical probability of a background fluctuation) in the sum of candidates from prompt J/ψ, ψ(2S), Υ(1S),Υ(2S) and Υ(3S) relative to the estimated background.

2 data tables
Table 1

The analysis of hadrons (from X) provides to distinguish of the various decay modes of Z-boson (see text).

Table 2

No description provided.


Measurement of the average b baryon lifetime and the product branching ratio f (b --> Lambda(b)) x BR (Lambda(b) --> Lambda lepton- anti-neutrino X)

The OPAL collaboration Akers, R. ; Alexander, G. ; Allison, John ; et al.
Z.Phys.C 69 (1996) 195-214, 1996.
Inspire Record 397395 DOI 10.17182/hepdata.51966

None

1 data table
Table 1

Charged conjugate state is assumed.


rivet Analysis
B* production in Z decays

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adye, T. ; et al.
Z.Phys.C 68 (1995) 353-362, 1995.
Inspire Record 395026 DOI 10.17182/hepdata.52359

None

2 data tables
Table 1

No description provided.

Table 2

No description provided.