Hadroproduction of the chi1 and chi2 states of charmonium in 800-GeV/c proton silicon interactions.

The E771 collaboration Alexopoulos, T. ; Antoniazzi, L. ; Arenton, M. ; et al.
Phys.Rev.D 62 (2000) 032006, 2000.
Inspire Record 504991 DOI 10.17182/hepdata.41516

The cross sections for the hadroproduction of the Chi1 and Chi2 states of charmonium in proton-silicon collisions at sqrt{s}=38.8 GeV have been measured in Fermilab fixed target Experiment 771. The Chi states were observed via their radiative decay to J/psi+gamma, where the photon converted to e+e- in the material of the spectrometer. The measured values for the Chi1 and Chi2 cross sections for x_F>0 are 263+-69(stat)+-32(syst) and 498+-143(stat)+-67(syst) nb per nucleon respectively. The resulting sigma(Chi1}/sigma(Chi2) ratio of 0.53+-0.20(stat)+-0.07(syst), although somewhat larger than most theoretical expectations, can be accomodated by the latest theoretical estimates.

1 data table

No description provided.


DIFFERENCES BETWEEN PROTON AND PI- INDUCED PRODUCTION OF THE CHARMONIUM CHI STATES

Bauer, Daniel A. ; Graff, T.L. ; Lukens, P.T. ; et al.
Phys.Rev.Lett. 54 (1985) 753-756, 1985.
Inspire Record 216287 DOI 10.17182/hepdata.20333

The charmonium χ states are observed in both π− and p Be interactions near 200 GeV/c via their radiative decay into J/ψ. The χ(3510) and χ(3555) are produced with roughly equal cross sections in π− collisions while the χ(3555) dominates in p collisions. Simple gluon fusion can account for χ production with incident protons but additional mechanisms are needed for incident π−.

1 data table

No description provided.