Dr Elizabeth Gallas

Abstract:

We report on a study of the ratio of inclusive three-jet to inclusive two-jet production cross sections as a function of total transverse energy in pp̄ collisions at a center-of-mass energy √s = 1.8 TeV, using data collected with the DO detector during the 1992-1993 run of the Fermilab Tevatron Collider. The measurements are used to deduce preferred renormalization scales in perturbative script O (αs3) QCD calculations in modeling soft-jet emission. © 2001 The American Physical Society.

Abstract:

A new measurement of the pseudorapidity (η) and transverse-energy (ET) dependence of the inclusive jet production cross section was carried out. The differential cross section d²σ/(dETdη) was considered as a function of jet ET in five intervals of up to |η| = 3. Results were compared with next-to-leading order predictions from QCD.

Abstract:

The search for large extra spatial dimensions at hadron colliders was performed by looking for effects of virtual Kaluza-Klein gravitons in the production of dielectrons and diphotons at high energies. No evidence was found for large extra dimension (ED). A model-independent 95% C.L. upper limit of 0.46 TeV^-4 was set on the parameter nG.

Abstract:

We apply a quasi-model-independent strategy (“SLEUTH”) to search for new high [Formula Presented] physics in ≈100 [Formula Presented] of [Formula Presented] collisions at [Formula Presented] collected by the DØ experiment during 1992–1996 at the Fermilab Tevatron. Over 32 [Formula Presented] [Formula Presented] [Formula Presented] and [Formula Presented] exclusive final states are systematically analyzed for hints of physics beyond the standard model. Simultaneous sensitivity to a variety of models predicting new phenomena at the electroweak scale is demonstrated by testing the method on a particular signature in each set of final states. No evidence of new high [Formula Presented] physics is observed in the course of this search, and we find that 89% of an ensemble of hypothetical similar experimental runs would have produced a final state with a candidate signal more interesting than the most interesting observed in these data. © 2001 The American Physical Society.

Abstract:

We report on a search for supersymmetry using the DØ detector. The 1994-1996 data sample of √s = 1.8 TeV pp̄ collisions was analyzed for events containing two leptons (e or μ), two or more jets, and missing transverse energy. Assuming the minimal supergravity model, with A0 = 0 and μ < 0, various thresholds were employed to optimize the search. No events were found beyond expectation from the background. We set a lower limit at the 95% C.L. of 255 GeV/c2 for equal mass squarks and gluinos for tan β = 2, and present exclusion contours in the (m0, m1/2) plane for tan β = 2-6.