Measurement of the average lifetime of hadrons containing bottom quarks

Technical Report · Sun Jun 01 04:00:00 EDT 1986

DOI:https://doi.org/10.2172/5491295· OSTI ID:5491295

Klem, D E

This thesis reports a measurement of the average lifetime of hadrons containing bottom quarks. It is based on data taken with the DELCO detector at the PEP e/sup +/e/sup -/ storage ring at a center of mass energy of 29 GeV. The decays of hadrons containing bottom quarks are tagged in hadronic events by the presence of electrons with a large component of momentum transverse to the event axis. Such electrons are identified in the DELCO detector by an atmospheric pressure Cherenkov counter assisted by a lead/scintillator electromagnetic shower counter. The lifetime measured is 1.17 psec, consistent with previous measurements. This measurement, in conjunction with a limit on the non-charm branching ratio in b-decay obtained by other experiments, can be used to constrain the magnitude of the V/sub cb/ element of the Kobayashi-Maskawa matrix to the range 0.042 (+0.005 or -0.004 (stat.), +0.004 or -0.002 (sys.)), where the errors reflect the uncertainty on tau/sub b/ only and not the uncertainties in the calculations which relate the b-lifetime and the element of the Kobayashi-Maskawa matrix.

• Research Organization: Stanford Linear Accelerator Center, Menlo Park, CA (USA)
• DOE Contract Number: AC03-76SF00515
• OSTI ID: 5491295
• Report Number(s): SLAC-300; ON: DE86014070
• 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
ALKANES
BEAUTY PARTICLES
BRANCHING RATIO
BUTANE
CHERENKOV COUNTERS
DATA
DECAY
DRIFT CHAMBERS
ELECTRONS
ELEMENTARY PARTICLES
ELEMENTS
EXPERIMENTAL DATA
FERMIONS
FIELD THEORIES
HEAVY LEPTONS
HYDROCARBONS
IMPACT PARAMETER
INFORMATION
KOBAYASHI-MASKAWA MATRIX
LEPTONS
LIFETIME
LINEAR MOMENTUM
MATRICES
MEASURING INSTRUMENTS
MONTE CARLO METHOD
MULTIWIRE PROPORTIONAL CHAMBERS
NITROGEN
NONMETALS
NUMERICAL DATA
ORGANIC COMPOUNDS
PARTICLE DECAY
PEP STORAGE RINGS
POSTULATED PARTICLES
PROPORTIONAL COUNTERS
RADIATION DETECTORS
SHOWER COUNTERS
STORAGE RINGS
TAU PARTICLES
TRANSVERSE MOMENTUM
UNIFIED-FIELD THEORIES