Search for hadronic resonance in multijet final states with the CDF detector

Seitz, Claudia

Fermi National Accelerator Laboratory

关键词: A Centers;    Protons;    Quantum Chromodynamics;    Fermilab Tevatron;    Fermilab Collider Detector;   

DOI  :  10.2172/1000985
RP-ID  :  FERMILAB-MASTERS-2011-01
RP-ID  :  AC02-07CH11359
RP-ID  :  1000985

美国|英语

来源: UNT Digital Library

【 摘 要 】

This thesis describes a search for a new hadronic resonance in 3.2 fb{sup -1} of data using the Collider Detector at Fermilab. The Fermilab Tevatron accelerator collides beams of protons and antiprotons at a center of mass energy of {radical}s = 1.96 TeV. A unique approach is presented to extract multijet resonances from the large QCD background. Although the search is model independent, a pair produced supersymmetric gluino decaying through R-parity violation into three partons each is used to test our sensitivity to new physics. We measure these partons as jets, and require a minimum of six jets in an event. We make use of the kinematic features and correlations and use an ensemble of jet combinations to distinguish signal from multijet QCD backgrounds. Our background estimates also include all-hadronic t{bar t} decays that have a signature similar to signal. We observe no significant excess in an invariant mass range of 77 GeV/c{sup 2} to 240 GeV/c{sup 2} and place 95% C.L. limits on {sigma}(p{bar p} {yields} {tilde g}{tilde g} {yields} 3jets + 3jets) as a function of gluino invariant mass.