Study of charmonium chi states produced in proton and negative pion interactions with a beryllium target

Thesis/Dissertation · Tue Jan 01 04:00:00 EST 1985

OSTI ID:5613310

Wilson, J R

We have observed the production of charmonium in ..pi../sup -/-Be interactions at 190 GeV and p-Be interactions at 200 and 250 GeV. We detected the states chi(3510) and chi(3555) (chi/sub 1/ and chi/sub 2/) through their decay to j/psi + ..gamma... For ..pi../sup -/ production we measured sigma(chi/sub 1/)/sigma(chi/sub 2/) = 1.2 +/- 0.8 and found the fraction of J/psis coming from chi decay (F/sub psi chi/) to be 0.35 +/- 0.13. We see no clear chi/sub 1/ signal in the proton sample, so we quote a 90% confidence level upper limit of sigma(chi/sub 1/)/sigma(chi/sub 2/) < 0.72. We measure F/sub psi chi/ = 0.54 +/- 0.25 for production by a proton beam. The J/psi samples for each beam were divided in half based on the x/sub F/ of the J/psi. In the ..pi../sup -/ sample of J/psis with x/sub F/ greater than or equal to 0.43 we found sigma(chi/sub 1/)sigma(chi/sub 2/) = 0.70 +/- 0.44 and f/sub psi chi/ = 0.41 +/- 0.16; for the ..pi../sup -/ sample with x/sub F/ < 0.43, F/sub psi chi/ = 0.27 +/- 0.11. In the proton sample of J/psis with x/sub F/ greater than or equal to 0.31 we found F/sub psi chi/ = 0.77 +/- 0.42 and for J/psis with x/sub F/ < 0.31 we found F/sub psi chi/ = 0.24 +/- 0.38. The differences in charmonium production for different beam particles and x/sub F/ regions disagree with the predictions of the color nonsinglet model. It may be possible to account for these differences using color singlet processes only.

• Research Organization: Purdue Univ., Lafayette, IN (USA)
• OSTI ID: 5613310
• Country of Publication: United States
• Language: English

Related Subjects

645104* -- High Energy Physics-- Particle Interactions &amp; Properties-Experimental-- Strong Meson-Induced Interactions-- (-1987)
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ALKALINE EARTH METALS
BARYON REACTIONS
BERYLLIUM
CHARGED-PARTICLE REACTIONS
CHI-3500 RESONANCES
CHI-3550 RESONANCES
COLOR MODEL
COMPOSITE MODELS
CROSS SECTIONS
DATA
ELEMENTS
EXPERIMENTAL DATA
HADRON REACTIONS
INFORMATION
MATHEMATICAL MODELS
MESON REACTIONS
METALS
NUCLEAR REACTIONS
NUCLEON REACTIONS
NUMERICAL DATA
PARTICLE MODELS
PARTICLE PRODUCTION
PION MINUS REACTIONS
PION REACTIONS
PROTON REACTIONS
PSI-3105 RESONANCES
QUARK MODEL