MULTIPLE-PION PRODUCTION B 2-Bev $pi$$sup -$

Journal Article · Sun Apr 12 23:00:00 EST 1964 · Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D

DOI:https://doi.org/10.1103/PhysRev.134.B207· OSTI ID:4082762

Satterblom, P H; Walker, W D; Erwin, A R

A report is given of a study of pion-proton interactions in a liquid- hydrogen bubble chamber. A 2.1-Bev/c negative pion beam incident upon a 14-in.- diam chamber caused interactions from which those with four charged secondaries were selected and measured. Fits were attempted to the following final states: 3 pi + p, 3 pi + p + pi /sup 0/, and 4 pi + n. By normalizing to a total cross section of 35.7 mb, the partial cross sections for the above-listed final states are foundto be 1.67 plus or minus 0.08, 1.17 plus or minus 0.06, and0.37 plus or minus 0.02 mb. The 3 pi + p reaction was found to be dominated by the production of the 3/2-3/2 pion-nucleon isobar. The cross section for this process is 0.53 plus or minus 0.05 mb. Evidence for the eta and omega mesons was found in the 3 pi + p + pi /sup 0/ final state. Their cross sections are 0.037 plus or minus 0.015 and 0.26 plus or minus 0.035 mb, respectively. A Dalitz plot for eta decays is presented. Evidence is given for a double peak in the neutral two-pion mass spectrum for 3 pi + p and 4 pi + n events. The peaks coincide with those attributed to the rho meson in other experiments. The second of the two peaks corresponds well with the mass of the omega /sup 0/. A branching ratio of ( omega /sup 0/ yields 2 pi )/( omega /sup 0/ yields 3 pi ) is found to be >0.1. An attempt is made to calculate the pion- pion cross section by isolating events with low momentum transfer to the isobar. In the virious processes, enhancement is found in the nucleon plus or minus 2 pi mass spectra corresponding to the T = 3/2 state of mass 1920 Mev. It is proposed that the elementary cross diagram can explain these effects. (auth)

• Research Organization: Univ. of Wisconsin, Madison
• NSA Number: NSA-18-014888
• OSTI ID: 4082762
• Journal Information: Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D, Journal Name: Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D Vol. Vol: 134; ISSN PHRVA
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

BEAMS
BRANCHING RATIO
BUBBLE CHAMBERS
CHARGED PARTICLES
CROSS SECTIONS
DALITZ PLOT
DECAY
ENERGY LEVELS
ENERGY RANGE
ETA RESONANCES
GEV RANGE
HYDROGEN
INTERACTIONS
ISOBARS
ISOSPIN
LIQUIDS
MASS
MEASURED VALUES
MOMENTUM
NEUTRONS
NUCLEONS
NUMERICALS
OMEGA RESONANCES
PHYSICS
PIONS
PIONS-MINUS
PRODUCTION
PROTONS
RESONANCE
RHO RESONANCES
SPECTRA
SPIN