Importance of initial-state radiation to the search for the top quark at hadron colliders

Journal Article · Fri Dec 01 04:00:00 EST 1989 · Physical Review (Section) D: Particles and Fields; (USA)

DOI:https://doi.org/10.1103/PhysRevD.40.3608· OSTI ID:7265800

Haim, D ^[1]

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1. Physics Department, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, Illinois 61801 (US)

A study was performed on initial-state radiation in the process of heavy-top-quark production, at hadron colliders (both the Fermilab Tevatron and the Superconducting Super Collider). In particular, we studied events with the hard subprocesses {ital gg}{r arrow}{ital t{bar t}} and {ital q{bar q}}{r arrow}{ital t{bar t}}, with the subsequent semileptonic decay {ital t{bar t}}{r arrow}{ital b{bar b}}+{ital l}{sup +}{ital l}{sup {minus}}+missing {ital p}{sub {ital T}}. Using the Webber-Marchesini Monte Carlo program herwig, we produced 5000 events of this process, using top-quark masses of 100, 150, and 200 GeV. We find that in the process of {ital t{bar t}} production, when the top quark is heavier than the {ital W} boson, the initial-state radiation produces jets that can obscure the nature of the {ital t{bar t}} decay. These jets, which are mainly gluon jets, pass all the widely used cuts that are set for top-quark detection. The events therefore look like multijet events, rather than pure two-jet events. We find that there are many pure two-jet events which consist of {ital b} or {ital {bar b}} jet plus an extra gluon jet. The effect is most prominent for top-quark mass near the {ital W} mass, 100 GeV in our case. For heavier top quark, 150 and 200 GeV, the cuts that are put on the leptons and the missing energy, which come off the top-quark decay, basically eliminate this effect. The significance of this effect will extend beyond the pure {ital t{bar t}} production channel, since it is resident in every subprocess at hadron colliders.

• OSTI ID: 7265800
• Journal Information: Physical Review (Section) D: Particles and Fields; (USA), Journal Name: Physical Review (Section) D: Particles and Fields; (USA) Vol. 40:11; ISSN PRVDA; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

645103* -- High Energy Physics-- Particle Interactions & Properties-Experimental-- Strong Interactions & Baryon & Meson Properties
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ACCELERATORS
B MESONS
BOSONS
CYCLIC ACCELERATORS
DECAY
ELEMENTARY PARTICLES
FERMILAB TEVATRON
FERMIONS
GLUONS
HADRON-HADRON INTERACTIONS
HADRONS
INTERACTIONS
JET MODEL
MASS
MATHEMATICAL MODELS
MESONS
MONTE CARLO METHOD
PARTICLE DECAY
PARTICLE INTERACTIONS
PARTICLE MODELS
PARTICLE PRODUCTION
PARTONS
POSTULATED PARTICLES
PSEUDOSCALAR MESONS
QUARKS
SEMILEPTONIC DECAY
STORAGE RINGS
SUPERCONDUCTING SUPER COLLIDER
SYNCHROTRONS
TOP PARTICLES
WEAK PARTICLE DECAY