Observation of the top quark

Conference · Mon May 01 04:00:00 EDT 1995

OSTI ID:81819

Greenlee, H

The DO collaboration reports on a search for the Standard Model top quark in p{bar p} collisions at {radical}s = 1.8 TeV at the Fermilab Tevatron, with an integrated luminosity of approximately 50 pb{sup {minus}1}. We have searched for t{bar t} production in the dilepton and single-lepton decay channels, with and without tagging of b quark jets. We observe 17 events with an expected background of 3.8 {plus_minus} 0.6 events. The probability for an upward fluctuation of the background to produce the observed signal is 2 {times} 10{sup {minus}6} (equivalent to 4.6 standard deviations). The kinematic properties of the excess events are consistent with top quark decay. We conclude that we have observed the top quark and measure its mass to be 199{sub {minus}21}{sup +19} (stat.) {plus_minus}22 (syst.) GeV/c{sup 2} and its production cross section to be 6.4 {plus_minus} 2.2 pb.

• Research Organization: Fermi National Accelerator Lab., Batavia, IL (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC02-76CH03000
• OSTI ID: 81819
• Report Number(s): FNAL/C--95/103-E; CONF-9503147--3; ON: DE95013002
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
CROSS SECTIONS
FERMILAB COLLIDER DETECTOR
FERMILAB TEVATRON
MASS SPECTRA
PARTICLE PRODUCTION
PROTON-ANTIPROTON INTERACTIONS
QUARKS
REST MASS
TOP PARTICLES
Z NEUTRAL BOSONS