J / psi production via chi(c) decays in 920-GeV pA interactions

The HERA-B collaboration Abt, I. ; Abyzov, A. ; Adams, M. ; et al.
Phys.Lett.B 561 (2003) 61-72, 2003.
Inspire Record 601830 DOI 10.17182/hepdata.57487

Using data collected by the HERA-B experiment, we have measured the fraction of J\psi's produced via radiative chi_c decays in interactions of 920 GeV protons with carbon and titanium targets. We obtained R_{\chi_c} = 0.32 \pm 0.06_{stat} \pm 0.04_{sys} for the fraction of J\psi from chi_c decays averaged over proton-carbon and proton-titanium collisions. This result is in agreement with previous measurements and is compared with theoretical predictions.

4 data tables

Ratio of CHIC to J/PSI production cross section in P C interactions for the E+ E- and MU+ MU- channels separately.

Ratio of CHI/C to J/PSI production cross section in P TI interactions for the E+ E- and MU+ MU- channels separately.

Averaged ratio of CHIC to J/PSI production cross section in P C and P Ti interactions.

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Measurement of the J/psi production cross section in 920-GeV/c fixed-target proton-nucleus interactions

The HERA-B collaboration Abt, I. ; Adams, M. ; Agari, M. ; et al.
Phys.Lett.B 638 (2006) 407-414, 2006.
Inspire Record 700309 DOI 10.17182/hepdata.57500

The mid-rapidity (dsigma_(pN)/dy at y=0) and total sigma_(pN) production cross sections of J/Psi mesons are measured in proton-nucleus interactions. Data collected by the HERA-B experiment in interactions of 920 GeV/c protons with carbon, titanium and tungsten targets are used for this analysis. The J/Psi mesons are reconstructed by their decay into lepton pairs. The total production cross section obtained is sigma_(pN)(J/Psi) = 663 +- 74 +- 46 nb/nucleon. In addition, our result is compared with previous measurements.

4 data tables

Cross section for the individual targets for the visible rapidity region.

Total cross section for the individual targets extrapolated to the full phase space.

Total cross section for P NUCLEON --> J/PSI X for the full phase space.

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Improved measurement of the b anti-b production cross section in 920-GeV fixed-target proton nucleus collisions.

The HERA-B collaboration Abt, I. ; Adams, M. ; Agari, M. ; et al.
Phys.Rev.D 73 (2006) 052005, 2006.
Inspire Record 700310 DOI 10.17182/hepdata.57501

A new measurement of the b-bbar production cross section in 920 GeV proton-nucleus collisions is presented by the HERA-B collaboration. The b-bbar production is tagged via inclusive bottom quark decays into J/psi mesons, by exploiting the longitudinal separation of J/psi->ll decay vertices from the primary proton-nucleus interaction point. Both e+e- and mu+mu- channels are reconstructed, for a total of 83 +- 12 inclusive b->J/psi X events found. The combined analysis yields a b-bbar to prompt J/psi cross section ratio of ${\frac{{\Delta\sigma(bbbar)}}{{\Delta\sigma_{\jpsi}}}} = 0.032\pm 0.005 \stat \pm 0.004 \sys$ measured in the x_f acceptance (-0.35 <x_f <0.15), extrapolated to $\sigma(bbbar) = 14.9 \pm 2.2 \stat \pm 2.4 \sys $ nb/nucleon in the total phase space.

7 data tables

Ratio of prompt J/PSI to B-BBAR production cross section in P C interactions in the Feynmann X range -0.35 to 0.15 for the E+ E- and MU+ MU- channels separately and combined.

Ratio of prompt J/PSI to B-BBAR production cross section in P TI interactions in the Feynmann X range -0.35 to 0.15 for the E+ E- and MU+ MU- channels separately and combined.

Ratio of prompt J/PSI to B-BBAR production cross section in P WT interactions in the Feynmann X range -0.35 to 0.15 for the E+ E- and MU+ MU- channels separately and combined.

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J/psi Production by 24-GeV/c Protons

The Annecy(LAPP)-Brussels-Freiburg collaboration Bamberger, A. ; Binon, F.G. ; Bricman, C. ; et al.
Nucl.Phys.B 134 (1978) 1-13, 1978.
Inspire Record 122150 DOI 10.17182/hepdata.35143

We report measurements at the CERN PS of the production cross section of J/ψ(3.1) by 24 GeV protons on hydrogen, carbon, and tungsten.

2 data tables

No description provided.

ASSUME B.R.(E+E-) =0.069.