501 Matching Results

This system will be undergoing maintenance January 24th 9:00-11:00AM CST.

Search Results

Advanced search parameters have been applied.

Z' Bosons, the NuTeV Anomaly, and the Higgs Boson Mass

Description: Fits to the precision electroweak data that include the NuTeV measurement are considered in family universal, anomaly free U(1) extensions of the Standard Model. In data sets from which the hadronic asymmetries are excluded, some of the Z{prime} models can double the predicted value of the Higgs boson mass, from {approx} 60 to {approx} 120 GeV, removing the tension with the LEP II lower bound, while also modestly improving the {chi}{sup 2} confidence level. The effect of the Z{prime} models on both m{sub H} and the {chi}{sup 2} confidence level is increased when the NuTeV measurement is included in the fit. Both the original NuTeV data and a revised estimate by the PDG are considered.
Date: March 3, 2009
Creator: Chanowitz, Michael S
Partner: UNT Libraries Government Documents Department

Will at least one of the Higgs bosons of the next-to-minimal supersymmetric extension of the standard model be observable at LEP2 or the LHC?

Description: We demonstrate that there are regions of parameter space in the next-to-minimal (i.e. two-Higgs-doublet, one-Higgs-singlet superfield) supersymmetric extension of the SM for which none of the Higgs bosons are observable either at LEP2 with $\sqrt{s}=192 GeV$ and an integrated luminosity of $L=1000inverse pb$ or at the LHC with $L=600 inverse fb$.
Date: June 24, 1996
Creator: Gunion, John F.; Haber, Howard E. & Moroi, Takeo
Partner: UNT Libraries Government Documents Department

Higgs Mass Constraints on a Fourth Family: Upper and Lower Limits on CKM Mixing

Description: Theoretical and experimental limits on the Higgs boson mass restrict CKM mixing of a possible fourth family beyond the constraints previously obtained from precision electroweak data alone. Existing experimental and theoretical bounds on m{sub H} already significantly restrict the allowed parameter space. Zero CKM mixing is excluded and mixing of order {theta}{sub Cabbibo} is allowed. Upper and lower limits on 3-4 CKM mixing are exhibited as a function of m{sub H}. We use the default inputs of the Electroweak Working Group and also explore the sensitivity of both the three and four family fits to alternative inputs.
Date: June 25, 2010
Creator: Chanowitz, Michael S.
Partner: UNT Libraries Government Documents Department

Top and higgs at the Tevatron: Measurements, searches, prospects

Description: In this paper we summarize the status of Top Quark Physics and of searches for the Standard Model Higgs at the Tevatron. Results from both the CDF and D0 experiments are discussed and the prospects for the upcoming Run 2, in the year 2000, are outlined. Much work has been performed on these topics and due to the nature of these proceedings only a brief explanation can be offered here. For more details the reader should turn to the excellent sources listed in the reference section.
Date: May 11, 1999
Creator: Konigsberg, J.
Partner: UNT Libraries Government Documents Department

A Constrained Standard Model: Effects of Fayet-Iliopoulos Terms

Description: In [1]the one Higgs doublet standard model was obtained by an orbifold projection of a 5D supersymmetric theory in an essentially unique way, resulting in a prediction for the Higgs mass m_H = 127 +- 8 GeV and for the compactification scale 1/R = 370 +- 70 GeV. The dominant one loop contribution to the Higgs potential was found to be finite, while the above uncertainties arose from quadratically divergent brane Z factors and from other higher loop contributions. In [3], a quadratically divergent Fayet-Iliopoulos term was found at one loop in this theory. We show that the resulting uncertainties in the predictions for the Higgs boson mass and the compactification scale are small, about 25percent of the uncertainties quoted above, and hence do not affect the original predictions. However, a tree level brane Fayet-Iliopoulos term could, if large enough, modify these predictions, especially for 1/R.
Date: October 7, 2001
Creator: Barbieri, Riccardo; Hall, Lawrence J. & Nomura, Yasunori
Partner: UNT Libraries Government Documents Department

Study of Dark Matter inspired cMSSM scenarios at a TeV-class Linear Collider

Description: The accuracy in the measurement of the masses of sleptons and heavy Higgs bosons in cMSSM scenarios, compatible with the WMAP result on cold dark matter, has been re-analysed in view of the requirements for predicting this density to a few percent level from SUSY measurements at the linear collider.
Date: October 8, 2004
Creator: Battaglia, Marco
Partner: UNT Libraries Government Documents Department

Models of Scherk-Schwarz Symmetry Breaking in 5D: Classification and Calculability

Description: The form of the most general orbifold breaking of gauge, global and supersymmetries with a single extra dimension is given. In certain theories the Higgs boson mass is ultraviolet finite due to an unbroken local supersymmetry, which is explicitly exhibited. We construct: a 1 parameter SU(3) \times SU(2) \times U(1) theory with 1 bulk Higgs hypermultiplet, a 2 parameter SU(3) \times SU(2) \times U(1) theory with 2 bulk Higgs hypermultiplets, and a 2 parameter SU(5) \to SU(3) \times SU(2) \times U(1) theory with 2 bulk Higgs hypermultiplets, and demonstrate that these theories are unique. We compute the Higgs mass and compactification scale in the SU(3) \times SU(2) \times U(1) theory with 1 bulk Higgs hypermultiplet.
Date: July 1, 2001
Creator: Barbieri, Riccardo; Hall, Lawrence J. & Nomura, Yasunori
Partner: UNT Libraries Government Documents Department

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 the Standard Model.
Date: November 19, 2002
Creator: Chertok, M.; Dienes, K.; Godfrey, S.; Kalyniak, P.; Kaplan, D.; Kribs, G. D. et al.
Partner: UNT Libraries Government Documents Department

Supersymmetric Higgs Boson Pair Production: Discovery Prospects at Hadron Colliders

Description: We study the potential of hadron colliders in the search for the pair production of neutral Higgs bosons in the framework of the Minimal Supersymmetric Standard Model. We perform a detailed signal and background analysis, working out efficient kinematical cuts for the extraction of the signal. The important role of squark loop contributions to the signal is re-emphasized. If the signal is sufficiently enhanced by these contributions, it could even be observable at the next run of the upgraded Tevatron collider in the near future. At the LHC the pair production of light and heavy Higgs bosons might be detectable simultaneously.
Date: September 15, 1999
Creator: Mizukoahi, Jose K.
Partner: UNT Libraries Government Documents Department

Radiative higgs boson decays H {yields} f{anti f}{gamma}

Description: Higgs boson radiative decays of the form H {r_arrow} f{ovr f}{gamma} are calculated in the Standard Model using the complete one-loop expressions for the decay amplitudes. Contributions to the radiative width from leptons and light quarks are given. We also present e{ovr e} invariant mass distributions for H {r_arrow} e{ovr e}{gamma}, which illustrate the importance of the photon pole contribution and the effects of the box diagrams. 4 refs., 6 figs.
Date: October 10, 1996
Creator: Abbasabadi, A.; Bowser-Chao, D.; Repko, W.W. & Dicus, D.A.
Partner: UNT Libraries Government Documents Department

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} before LHC era. The study of top at the Tevatron has moved from discovery phase to one of characterizing its properties. The combined result of top quark mass is 174.3 {+-} 5.1 GeV/c{sup 2} ({delta}m{sub t} =m{sub t} < 3%).
Date: April 19, 1999
Creator: Yao, W.-M.
Partner: UNT Libraries Government Documents Department

SUSY searches at the Tevatron

Description: Current results of searches for Supersymmetry from the CDF and D0 collaborations are summarized. Analyses include searches in jets and missing E{sub t}, leptons and missing E{sub t}, and searches for charged and neutral Higgs particles. The CDF ee{gamma}{gamma}E {sub t} event and related analyses are presented.
Date: August 1, 1997
Creator: Culbertson, R. & Collaborations, CDF and D0
Partner: UNT Libraries Government Documents Department

Studies of the top quark at the Tevatron

Description: We report on studies of the top quark, beyond the measurements of its mass and produciton cross section, which have been carried out recently by the CDF and D0 collaborations, based on {approximately}110{+-}6 pb{sup -1} of proton-antiproton collisions at a center-of-mass energy of 1.8 TeV. Each experiment has searched for t{yields}H{sup +}b decays and, from the lack of observable signal, excluded previously unexplored regions of the [M{sub H+},tan{beta}] parameter space. D0 has studied the correlation between the spin states of pair-produced top quarks, and CDF has studied the helicity of the W bosons produced in the decay of top quarks. Within large statistical uncertainties, both measurements agree with predictions of the standard model.
Date: May 28, 1999
Creator: Chakraborty, Dhiman
Partner: UNT Libraries Government Documents Department

Prospects for higgs at the Tevatron

Description: The current status of simulation studies for the observation of a standard-model or lightest supersymmetric Higgs boson at TeV33 are reviewed. Latest studies indicate that the mass range 60 < m{sub H} {approx_lt} 130 GeV can be covered at the 5-standard-deviation level with 30 fb{sup -1}, using the WH and ZH channels. This is the full allowed mass range for the lightest Higgs h of minimal supersymmetry.
Date: February 1, 1998
Creator: Womersley, J.
Partner: UNT Libraries Government Documents Department

Present searches for Higgs signatures at the Tevatron

Description: We present results for various searches for signatures of standard and non-standard model Higgs boson decays conducted at the collider detectors CDF and D0 using {approx}100 pb{sup -1} of integrated luminosity each from the Tevatron collider Run 1 (1992-96) at {radical}s=1.8 TeV. No evidence for a Higgs boson decay is found and various limits are set.
Date: August 1, 1997
Creator: Groer, L.
Partner: UNT Libraries Government Documents Department

Top quark physics: Overview

Description: In this presentation I will primarily focus on top quark physics but I will include a discussion of the W-boson mass and the possibility of discovering a light Higgs boson via associated production at the Tevatron.
Date: January 1, 1998
Creator: Parke, S.
Partner: UNT Libraries Government Documents Department

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 14, 1999
Creator: Roco, Maria Teresa P.
Partner: UNT Libraries Government Documents Department

Higgs searches at the Tevatron in Run I

Description: This paper summarizes recent Higgs searches in p{anti p} collisions at {radical}s = 1.8 TeV from the Tevatron using Run I data. Emphasis is given to a new result from the CDF collaboration in searching for neutral minimal SUSY Higgs bosons through the four jet reaction p{anti p} {yields} b{anti b}{phi} {yields} b{anti b}b{anti b}. Both the CDF and D0 experiments have also searched for standard model as well as other non-standard Higgs signatures in the mass region below ~ 140 GeV/c&sup2; with no evidence of new physics.
Date: October 7, 1999
Creator: Valls, Juan A.
Partner: UNT Libraries Government Documents Department

Higgs searches in run 2 at the Tevatron

Description: In Run 2 at the Tevatron, the upgraded CDF and D0 experiments will have greatly improved sensitivity in the search for the Higgs bosons of the Standard Model and minimal supersymmetry. In the past year the Higgs Working Group of the Tevatron Run 2 SUSY/Higgs Workshop has estimated the discovery and exclusion reach for the Higgs, combining all possible search channels and utilizing all the upgraded features of both detectors. The results give strong motivation to continue the next run of the Tevatron into Run 3, with an eventual goal of up to 20 fb<sup>-1</sup> or more delivered per experiment.
Date: July 13, 1999
Creator: Conway, John S.
Partner: UNT Libraries Government Documents Department

Non-SUSY exotic particle searches at the Tevatron

Description: Between 1992 and 1995, the CDF and D0 collaborations collected data from p{anti p} collisions at {radical}s = 1.8 TeV. Recently, several analyses of this data have been performed in search of evidence for various non-Supersymmetric exotic particles. As no evidence for the existence of these particles is observed, confidence level limits are established for exotic particle predictions from various theoretical models. Analyses presented here include searches for Standard Model Higgs, technicolor particles, topcolor-assissted technicolor bosons, and flavor-universal colorons.
Date: June 29, 1999
Creator: Cassada, J.
Partner: UNT Libraries Government Documents Department

Top and higgs physics at the Tevatron

Description: We present a summary of our experimental understanding of the top quark and discuss the significant improvements expected in Run II at the Fermilab Tevatron Collider. We also discuss prospects for a Higgs boson discovery at the Tevatron.
Date: December 23, 2002
Creator: Savard, Pierre
Partner: UNT Libraries Government Documents Department

Higgs boson production at hadron colliders: Signal and background processes

Description: We review the theoretical status of signal and background calculations for Higgs boson production at hadron colliders. Particular emphasis is given to missing NLO results, which will play a crucial role for the Tevatron and the LHC.
Date: January 12, 2004
Creator: Rainwater, David; Spira, Michael & Zeppenfeld, Dieter
Partner: UNT Libraries Government Documents Department

Implications of the LHC two-photon signal for two-Higgs-doublet models

Description: We study the implications for Two Higgs Doublet Models of the recent announcement at the LHC giving a tantalizing hint for a Higgs boson of mass 125 GeV decaying into two photons. We require that the experimental result be within a factor of two of the theoretical Standard Model prediction, and analyze the type I and type II models as well as the lepton-specific and flipped models, subject to this requirement. It is assumed that there is no new physics other than two Higgs doublets. In all of the models, we display the allowed region of parameter space taking the recent LHC announcement at face value, and we analyze the W{sup +}W{sup -}, ZZ, {bar b}b and {tau}{sup +}{tau}{sup -} expectations in these allowed regions. Throughout the entire range of parameter space allowed by the {gamma}{gamma} constraint, the number of events for Higgs decays into WW, ZZ and b{bar b} are not changed from the Standard Model by more than a factor of two. In contrast, in the Lepton Specific model, decays to {tau}{sup +}{tau}{sup -} are very sensitive across the entire {gamma}{gamma}-allowed region.
Date: April 1, 2012
Creator: P. M. Ferreira, Rui Santos, Marc Sher, Joao P. Silva
Partner: UNT Libraries Government Documents Department