Search for charm in pion and anti-proton interactions near threshold. [8. 5 to 15. 0, cross sections, branching ratios]

Technical Report · Mon Aug 01 04:00:00 EDT 1977

DOI:https://doi.org/10.2172/5235304· OSTI ID:5235304

Kadel, R W

A search is reported for charmed particles produced by antiprotons of momentum 15.0, 12.4, and 8.5 GeV/c and pions of momentum 15.0 and 10.5 GeV/c. Charged particles emerging from a carbon target near 90/sup 0/ in the center of mass (18/sup 0/ lab) were detected in a double arm spectrometer with a low momentum cutoff of P/sub lab/ greater than or equal to 1 GeV/c. The best upper limit is the process anti PN ..-->.. D/sup 0/( anti D/sup 0/) + X, where the D/sup 0/ (anti D/sup 0/) decays into K/sup -/ - ..pi../sup +/ (K/sup +/ - ..pi../sup -/), is: sigmaB = 780 +- 300 nb at a beam momentum of 8.5 GeV/c. For the 10.5 GeV/c pion running the trigger was restricted by requiring the presence of a slow forward pion in a third spectrometer area, in coincidence with the usual double arm trigger. The acceptance of the third arm was chosen to include pions from the decay of the charmed D*/sup -/ meson, which has a very small Q value. The upper limit for the process: ..pi../sup -/N ..-->.. D*/sup -/ + X, D*/sup -/ ..-->.. ..pi../sup -/ + anti D/sup 0/, anti D/sup 0/ ..-->.. K/sup +/ + ..pi../sup -/ is sigmaB = 16 +- 16 nb. Additionally, a measurement of inclusive K* (1421) production in anti-proton interactions at 8.5 GeV/c is reported. The cross-section times branching ratio is: sigma(anti PN ..-->.. K*(1421) + X)*B/sub K*..-->..K..pi../ = 4. +- .8 x 10/sup -29/ cm/sup 2/. (JFP)

• Research Organization: Princeton Univ., N.J. (USA). Elementary Particles Lab.
• Sponsoring Organization: USDOE
• DOE Contract Number: EY-76-C-02-3072
• OSTI ID: 5235304
• Report Number(s): COO-3072-89
• Country of Publication: United States
• Language: English

Related Subjects

645104* -- High Energy Physics-- Particle Interactions & Properties-Experimental-- Strong Meson-Induced Interactions-- (-1987)
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ANTINUCLEON REACTIONS
ANTIPROTON REACTIONS
BARYON REACTIONS
BOSONS
BRANCHING RATIO
CARBON
CHARGED PARTICLES
CHARGED-PARTICLE REACTIONS
CHARM PARTICLES
CROSS SECTIONS
D RESONANCES
DECAY
ELEMENTARY PARTICLES
ELEMENTS
ENERGY
ENERGY RANGE
GEV RANGE
GEV RANGE 01-10
GEV RANGE 10-100
HADRON REACTIONS
HADRONS
K RESONANCES
K)RESONANCES
K-1420 RESONANCES
LINEAR MOMENTUM
MESON REACTIONS
MESON RESONANCES
MESONS
NONMETALS
NUCLEAR REACTIONS
NUCLEON REACTIONS
PION REACTIONS
POSTULATED PARTICLES
Q-VALUE
RESONANCE PARTICLES
STRANGE PARTICLES
TENSOR MESONS