Inclusive D meson production with the Mark II detector at SPEAR. [3. 9 to 7. 4 GeV (c. m. )]

Technical Report · Mon Sep 01 04:00:00 EDT 1980

DOI:https://doi.org/10.2172/6815315· OSTI ID:6815315

Coles, M W

Neutral and charged D meson production cross sections were measured at center-of-mass energies between 3.9 GeV and 7.4 GeV. The quantity R/sub D/(=(sigma/sub D/sup +/+D/sup -// + sigma/sub D/sup 0/+ anti D/sup 0//)/2 sigma/sub ..mu../sup +/..mu../sup -//) is equal to 2 at 4 GeV and 4.4 GeV and about equal to 1 elsewhere. R/sub D/ + 2.5 approximately equals R (sigma/sub hadrons//sigma/sub ..mu../sup +/..mu../sup -//) at all energies. The exclusive cross sections for e/sup +/e/sup -/ annihilation into D anti D, D* anti D, and D* anti D* were measured at center-of-mass energies between 3.9 GeV and 4.3 GeV. sigma/sub D* anti D*/ decreases with increasing center-of-mass energy from 6.6 +- 1.3 nb near 4 GeV to 3.6 +- .9 nb near 4.3 GeV. sigma/sub D* anti D/ also decreases from 4.2 +- .9 nb to 1.8 +- .6 nb over the same energy region. sigma/sub D anti D/ is less than 0.5 +- .3 nb at all energies. The branching fractions for D*/sup +/ and D* decay were measured. B/sub D*/sup 0/..-->..D/sup 0/..pi../sup 0// = 0.5 +- .09, B/sub D*/sup +/..-->..D/sup 0/..pi../sup +// = 0.44 +- .10, and B/sub D*/sup +/..-->..D/sup +/..pi../sup 0// = 0.31 +- .07. At 5.2 GeV, the D meson differential cross section is well described by phase space for e/sup +/e/sup -/ ..-->.. D anti D..pi pi.. or D* anti D*..pi pi... Sd sigma/dz was parameterized as A(1-z)/sup n/ with n = 0.9 +- .4. Quasi-two-body production accounts for less than 20% of the total D cross section. No evidence was found for associated charmed baryon-D meson production. An upper limit of 0.4 nb (90% confidence level) was determined for associated production. 41 figures, 12 tables.

• Research Organization: California Univ., Berkeley (USA). Lawrence Berkeley Lab.
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 6815315
• Report Number(s): LBL-11513
• Country of Publication: United States
• Language: English

Related Subjects

645101* -- High Energy Physics-- Particle Interactions & Properties-Experimental-- Electromagnetic Interactions & Properties
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ANNIHILATION
BASIC INTERACTIONS
BOSONS
BRANCHING RATIO
CHARM PARTICLES
CHARMED MESON RESONANCES
CROSS SECTIONS
D RESONANCES
D-1865 RESONANCES
D-2007 RESONANCES
DATA
DECAY
DIFFERENTIAL CROSS SECTIONS
DRIFT CHAMBERS
ELECTROMAGNETIC INTERACTIONS
ELECTROMAGNETIC PARTICLE DECAY
ELECTRON-POSITRON INTERACTIONS
ELEMENTARY PARTICLES
ENERGY RANGE
EXPERIMENTAL DATA
GEV RANGE
GEV RANGE 01-10
GEV RANGE 10-100
HADRONIC PARTICLE DECAY
HADRONS
INCLUSIVE INTERACTIONS
INFORMATION
INTERACTIONS
LEPTON-LEPTON INTERACTIONS
MEASURING INSTRUMENTS
MESON RESONANCES
MESONS
MULTIWIRE PROPORTIONAL CHAMBERS
NUMERICAL DATA
PARTICLE DECAY
PARTICLE INTERACTIONS
PARTICLE PRODUCTION
POSTULATED PARTICLES
PROPORTIONAL COUNTERS
RADIATION DETECTORS
RADIATIVE DECAY
RESONANCE PARTICLES
SCINTILLATION COUNTERS
SHOWER COUNTERS
WEAK PARTICLE DECAY