Measurement of the Charged and Neutral D Meson Lifetimes

Technical Report · Sat Feb 01 00:00:00 EST 1986

DOI:https://doi.org/10.2172/1454010· OSTI ID:1454010

Butler, John Mark ^[1]

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1. SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States); Stanford Univ., CA (United States)

In an exposure of the SLAC Hybrid Facility (SHF) to a backward scattered laser beam, 136 charm events produced in γp interactions at 20 GeV have been observed. The SHF 1 m bubble chamber was equipped with a High Resolution Optics camera in order to detect directly the production and decay of charm particles. After imposing rigorous cuts, 48 charged, 40 neutral, and 2 topologically ambiguous decays remain. using a novel method for estimating the momentum of unconstrained decays, the D meson lifetimes from this samples are measured to be r_D⁺ = (8.6 ± 1.3$$^{+1.8}_{-0.3}$$) x 10^-13 sex and r_D⁰ = (6.1 ± 0.9 ± 0.3) x 10^-13 sec with a ratio of R = r_D^±/r_D⁰ = (1.4 ± 0.3$$^{+0.2}_{-0.1}$$). This value of R indicates the Spectator Model charm particle decay mechanism is the dominate piece in the D^± and D⁰ decay rates. Limits are placed on additional contributions to the D decay rates from other processes including W-exchange, Final State Interactions, and Pauli Principle Interference.

• Research Organization: SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• DOE Contract Number: AC02-76SF00515
• OSTI ID: 1454010
• Report Number(s): SLAC-R--290; SLAC-291
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS