Not available / text

The development of a neural network based electron finder designed for the ZEUS calorimeter is described. A study of elastic and inelastic J/ψ meson production in electron-proton collisions at HERA using the ZEUS detector is presented. During the 1993 and 1994 running periods, the ZEUS detector collected ~ 500 nb^-1 and ~ 3 pb^-1 of data respectively. The direct inelastic J/ψ photoproduction cross-section is measured for both running periods and an attempt is made to extract the gluon density inside the proton using the 1994 inelastic J/ψ sample.

Thesis (Ph. D.)--University of Texas at Austin, 2002. / Vita. Includes bibliographical references. Available also from UMI Company.

Thesis (Ph. D.)--Florida State University, 2004. / Advisor: Dr. Howard Baer, Florida State University, College of Arts and Sciences, Dept. of Physics. Title and description from dissertation home page (viewed Sept. 24, 2004). Includes bibliographical references.

Thesis (Ph. D.)--University of Texas at Austin, 2004. / Supervisors: Gerald W. Hoffmann and C. Fred Moore. Vita. "Center of mass energy" written as symbols in title. Includes bibliographical references. Also available from UMI.

Thesis presented in fulfilment of the requirements for the degree of Master of Science in Physics at the University of the Witwatersrand School of Physics, University of the Witwatersrand, 2015. / A search for the pseudoscalar A boson, which is predicted by in many models with an extended Higgs sector, gives a gateway to searches for physics beyond the Standard Model (SM). This thesis presents the results of a search for gluon-fusion produced A in the decay to Zh, with a final state of two electrons or muons and two τ leptons, in 20.3 fb−1of proton-proton collision data at √s = 8 TeV. Each tau lepton is allowed to dacay either leptonically, τlep, or hadronically,τhad, giving rise to three final states, τlepτlep, τlepτhad and τhadτhad. Focus is placed on the methodology and results of the fully hadronic channel. No evidence for the existence of an A boson is found in the scanned range of 220 ≤ mA ≤ 1000 GeV and 95% CL upper limits are placed on the gluon-fusion cross section times branching ratio, σ × BR(A → Zh) × BR(h → ℓℓττ). The results are combined with a complementing A → Zh search, where h → b¯b, and interpreted in view of two-Higgs-Doublet-Models (2HDMs), where exclusion limits are placed on large sections of phasepace.

Apresentamos um estudo fenomenológico de algumas extensões do modelo padrão da física de partículas no LEP e no LHC. Concentramos nossa atenção, em particular1 na busca por evidências de supersimetria com violação de paridade--R no LEP I, LEP II e LHC. Estudamos um modelo supersirnétrico com violação espontânea de paridade-R bem como um modelo efetivo onde a violação ocorre explicitamente. Realizamos, também, um estudo independente de modelo para leptoquarks no LHC a partir de colisões eq baseado em uma lagrangiana efetiva. Mostramos que os efeitos destas duas extensões do modelo padrão poderão ser visíveis no intervalo de energia dos aceleradores considerados. / We present a phenomenologic study of some extensions of standard model of elementary particles at LEP and LHC. We concentrate our attention, for instance, on the search of R-parity violating supersymmetry evidences at LEP I, LEP II and LHC. We study a spontaneous R-parity violating model as well an effective one where the violation occurs explicitly. We also perform an independent model study on leptoquarks at LHC coming from e q collisions, in the frame of an effective lagrangian. We show that the effects of these two standard model extensions can be visible in the range of energy of the chosen colliders.

No description available.

In preparations for the ATLAS experiment at the Large Hadron Collider at CERN, sections of the ATLAS Electromagnetic Endcap Calorimeter (EMEC) and Hadronic Endcap Calorimeter (HEC) were subjected to particle beams in the summer of 2002. The EMEC and HEC are non-compensating calorimeters with e/h > I: electromag¬netic showers will, on average; have a higher energy response than hadronic showers initiated by particles of the same energy. To reconstruct the energy of pions, the method of software compensation is investigated. Several beam energy dependent weighting schemes are studied, using calorimeter depth weights and cluster energy density weights. Finally, a beam energy independent cluster energy density weighting scheme is studied. Partial software compensation is achieved for pion energy recon¬struction, improving the energy resolution and response linearity of the calorimeters.

In preparation for the ATLAS experiment at the LHC at CERN. the high pseudorapidity region (|n| > 2.5) of the ATLAS end-cap liquid argon calorimeters underwent particle beam testing in 2004. One of the main goals of these tests is to study energy reconstruction in the complex interface region between the electromagnetic. hadronic, and forward calorimeters at. 1 - 3.2. These detectors were exposed to beams of electrons and pions with energies ranging from 6 GeV to 200 GeV. Three methods of calibration in the electromagnetic end-cap calorimeter (EMEC) are studied and compared to the results of a previous beam test. of the EMEC. The electromagnetic scale factor (aEM) is computed and compared to the previous beam test value. Studies of the energy response and resolution of the high pseudorapidity region of the three end-cap calorimeters to the particle beam position scans are given.