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Top physics: search for anomalous kinematics in t anti-t dilepton events at cdf ii

Description: We report on a search for anomalous kinematics of t{bar t} dilepton events in p{bar p} collisions at {radical}s = 1.96 TeV using 193 pb{sup -1} of data collected with the CDF II detector. We developed a new a priori technique designed to isolate the subset in a data sample revealing the largest deviation from standard model (SM) expectations and to quantify the significance of this departure. In the four-variable space considered, no particular subset shows a significant discrepancy and we find… more
Date: December 14, 2004
Creator: Acosta, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Top studies

Description: The top quark, discovered in 1994 at the Tevatron, has proven a very interesting particle. Its characteristics allow both to perform stringent tests of electroweak theory, and to search for new physics through a deviation from standard model predictions for several of its peculiar properties. I will review the status of top physics and briefly describe the potential of experiments of the near future.
Date: January 2, 2003
Creator: Dorigo, T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The CKM Experiment

Description: I describe the CKM experiment, a new initiative using the Fermilab Main Injector to obtain {approx} 100 events of the ultra-rare decay mode K{sup +} {yields} {pi}{sup +}{nu}{bar {nu}}. The branching ratio will be used to extract |V*{sub ts}V{sub td}|. Due to the decay mode's theoretical cleanliness, it plays a key role in over-constraining the Standard Model description of CP violation.
Date: October 25, 2002
Creator: Nguyen, Hogan H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Report of the subgroup on alternative models and new ideas

Description: We summarize some of the work done by the P3 subgroup on Alternative Models and New Ideas. The working group covered a broad range of topics including a constrained Standard Model from an extra dimension, a discussion of recent ideas addressing the strong CP problem, searches for doubly charged higgs bosons in e{gamma} collisions, and an update on discovery limits for extra neutral gauge bosons at hadron colliders. The breadth of topics rejects the many ideas and approaches to physics beyond th… more
Date: November 19, 2002
Creator: Chertok, M.; Dienes, K.; Godfrey, S.; Kalyniak, P.; Kaplan, D.; Kribs, G. D. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The Higgs Working Group: Summary Report.

Description: This working group has investigated Higgs boson searches at the Tevatron and the LHC. Once Higgs bosons are found their properties have to be determined. The prospects of Higgs coupling measurements at the LHC and a high-energy linear e{sup +}e{sup -} collider are discussed in detail within the Standard Model and its minimal supersymmetric extension (MSSM). Recent improvements in the theoretical knowledge of the signal and background processes are presented and taken into account. The residual … more
Date: August 1, 2005
Creator: Dawson, S. & AL., ET
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Standard model explanations for the NuTeV electroweak measurements

Description: The NuTeV Collaboration has measured the electroweak parameters sin{sup 2} {theta}{sub W} and {rho} in neutrino-nucleon deep-inelastic scattering using a sign-selected beam. The nearly pure {nu} or {bar {nu}} beams that result provide many of the cancellations of systematics associated with the Paschos-Wolfenstein relation. The extracted result for sin{sup 2} {theta}{sub W}(on-shell) = 1 - M{sub W}{sup 2}/M{sub Z}{sup 2} is three standard deviations from prediction. We discuss Standard Model ex… more
Date: December 23, 2003
Creator: Bernstein, R. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A high energy physics perspective

Description: The status of the Standard model and role of symmetry in its development are reviewed. Some outstanding problems are surveyed and possible solutions in the form of additional {open_quotes}Hidden Symmetries {close_quotes} are discussed. Experimental approaches to uncover {open_quotes}New Physics{close_quotes} associated with those symmetries are described with emphasis on high energy colliders. An outlook for the future is given.
Date: January 13, 1997
Creator: Marciano, W. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Supersymmetry, Naturalness, and Signatures at the LHC

Description: Weak scale supersymmetry is often said to be fine-tuned, especially if the matter content is minimal. This is not true if there is a large A term for the top squarks. We present a systematic study on fine-tuning in minimal supersymmetric theories and identify low energy spectra that do not lead to severe fine-tuning. Characteristic features of these spectra are: a large A term for the top squarks, small top squark masses, moderately large tan {beta}, and a small {mu} parameter. There are classe… more
Date: February 10, 2006
Creator: Kitano, Ryuichiro & Nomura, Yasunori
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Measurement of Interfacial Area Production and Permeability within Porous Media

Description: An understanding of the pore-level interactions that affect multi-phase flow in porous media is important in many subsurface engineering applications, including enhanced oil recovery, remediation of dense non-aqueous liquid contaminated sites, and geologic CO2 sequestration. Standard models of two-phase flow in porous media have been shown to have several shortcomings, which might partially be overcome using a recently developed model based on thermodynamic principles that includes interfacial … more
Date: January 1, 2010
Creator: Crandall, Dustin; Ahmadi, Goodarz & Smith, Duane H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Little Supersymmetry and the Supersymmetric Little Hierarchy Problem

Description: The current experimental lower bound on the Higgs mass significantly restricts the allowed parameter space in most realistic supersymmetric models, with the consequence that these models exhibit significant fine-tuning. We propose a solution to this `supersymmetric little hierarchy problem'. We consider scenarios where the stop masses are relatively heavy - in the 500 GeV to a TeV range. Radiative stability of the Higgs soft mass against quantum corrections from the top quark Yukawa coupling is… more
Date: April 22, 2004
Creator: Birkedal, Andreas; Chacko, Z. & Gaillard, Mary K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A measurement of forward-backward charge asymmetry of electron-positron pairs in proton-antiproton collision at 1.8 TeV

Description: The authors present a measurement of the mass dependence of the forward-backward charge asymmetry for e{sup +}e{sup -} pairs resulting from {gamma}*/Z decays with mass M{sub ee} > 40 GeV/c{sup 2}. The Run II data sample consists of 72 pb{sup -1} of data, which was collected by the CDF detector in {bar p}p collisions at {radical}s = 1.96 TeV at the Fermilab Tevatron. The measurement is compared with predictions from the Standard Model.
Date: December 1, 2003
Creator: Veramendi, Gregory Francisco
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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EVIDENCE FOR K+ YIELDS P+ VV-.

Description: The first observation of the decay K{sup +} {yields} {pi}{sup +}{nu}{ovr {nu}} has been reported. The E787 experiment presented evidence for the K{sup +} {yields} {pi}{sup +}{nu}{ovr {nu}} decay, based on the observation of a single clean event from data collected during the 1995 run of the AGS (Alternating Gradient Synchrotron at Brookhaven National Laboratory). The branching ratio indicated by this observation, B(K{sup +} {yields} {pi}{sup +}{nu}{ovr {nu}}) = 4.2{sub -3.5}{sup +9.7} x 10{sup … more
Date: December 18, 1998
Creator: Kettell, S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Ibs for Ion Distribution Under Electron Cooling.

Description: Standard models of the intra-beam scattering (IBS) are based on the growth of the rms beam parameters for a Gaussian distribution. As a result of electron cooling, the core of beam distribution is cooled much faster than the tails, producing a denser core. In this paper, we compare various approaches to IBS treatment for such distribution. Its impact on the luminosity is also discussed.
Date: May 16, 2005
Creator: Fedotov, A. V.; Ben-Zvi, Ilan; Eidelman, Yu.; Litvinenko, V. & Parzen, G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A select overview of neutrino experiments

Description: The relationship between the lepton sector and the quark sector is an interesting source of discourse in the current theoretical climate. Models that might someday supersede the Standard Model typically require quark structure, with implications for the lepton sector. This talk will explore some of the consequences of newer models, in the context of certain neutrino experiments.
Date: November 1, 2004
Creator: Stefanski, Raymond J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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ATLAS Note ATL-COM-PHYS-2009.

Description: The program InvMass has been developed to perform a general model-independent search for new particles using the ATLAS detector at the Large Hadron Collider (LHC), a proton-proton collider at CERN. The search is performed by examining statistically significant variations from the Standard Model predictions in exclusive event classes classified according to the number of identified objects. The program, called InvMass, finds all relevant particle groups identified with the ATLAS detector and ana… more
Date: December 22, 2009
Creator: Chekanov, S. & Boomsma, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Standard model higgs and top mass measurements at the Tevatron

Description: A summary of the present Standard Model Higgs search and measurement of top quark mass at the Tevatron are presented. The sensitivity of the present Higgs search at the Tevatron is limited by statistics to a cross section approximately two orders of magnitude higher than the predicted cross section for standard model Higgs production. With 30 fb{sup -1} of integrated luminosity, the Tevatron offers an unique potential discovery window for the Standard Model Higgs mass up to 130 GeV/c{sup 2} bef… more
Date: April 19, 1999
Creator: Yao, W.-M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fermion masses and anomalous dipole moments

Description: Fermion mass generation via quantum loops is briefly described. The potential for large anomalous dipole moments, {delta}a{sub f} {approx_equal} m{sub f}{sup 2}/M{sup 2}, in such schemes is demonstrated. Implications for the muon`s anomalous magnetic moment as well as the top quark`s chromo and electroweak moments are discussed.
Date: August 1, 1995
Creator: Marciano, William J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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CKM--Charged Kaons at the Main Injector

Description: The CKM experiment is a proposal to measure the branching ratio of the rare decay K{sup +} {r_arrow} {pi}{sup +} {nu}{bar {nu}} at the Main Injector at Fermilab using a decay in flight technique. The goal is to observe {approx}100 events, for a Standard Model branching ratio of 1 x 10{sup {minus}10} with a background of less than 10 events.
Date: January 16, 2001
Creator: Cooper, P.S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Prospects for higgs discovery at the Tevatron

Description: This report presents the results of a Fermilab study of the sensitivity for Higgs boson production at the upgraded Tevatron in Run II. The study extends previous Tevatron results by combining all possible search channels, considering the production of higher mass Higgs bosons and interpreting the results in the context of supersymmetric Higgs production as well as Standard Model production.
Date: October 25, 1999
Creator: Roco, Maria Teresa P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Search for Squarks and Gluinos in Events Containing Jets and a Large Imbalance in Transverse Energy

Description: Using data corresponding to an integrated luminosity of 79 pb{sup -1}, D0 has searched for events containing multiple jets and large missing transverse energy in p{bar p} collisions at {radical}s = 1.8 TeV at the Fermilab Tevatron collider. Observing no significant excess beyond what is expected from the standard model, they set limits on the masses of squarks and gluinos and on the model parameters m{sub 0} and m{sub 1/2}, in the framework of the minimal low-energy supergravity models of super… more
Date: February 1, 1999
Creator: Abbott, B.; Abolins, M.; Abramov, V.; Acharya, B. S.; Adam, I.; Adams, D. L. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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