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in subjects: "Higgs Bosons"

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Evidence for an excess of B to D(*) Tau Nu decays

Based on the full BABAR data sample, we report improved measurements of the ratios R(D{sup (*)}) = {Beta}({bar B} {yields} D{sup (*)} {tau}{sup -}{bar {nu}}{sub {tau}})/{Beta}({bar B} {yields} D{sup (*)} {ell}{sup -}{bar {nu}}{sub {ell}}), where {ell} is either e or {mu}. These ratios are sensitive to new physics contributions in the form of a charged Higgs boson. We measure R(D) = 0.440 {+-} 0.058 {+-} 0.042 and R(D*) = 0.332 {+-} 0.024 {+-} 0.018, which exceed the Standard Model expectations … more

Date: October 9, 2012

Creator: Lees, J. P.; Poireau, V.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Precision physics at LHC

In this talk the author gives a brief survey of some physics topics that will be addressed by the Large Hadron Collider currently under construction at CERN. Instead of discussing the reach of this machine for new physics, the author gives examples of the types of precision measurements that might be made if new physics is discovered.

Date: May 1, 1997

Creator: Hinchliffe, I.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Progress on muon{sup +}muon{sup {minus}} colliders

Advantages and disadvantages of muon colliders are discussed. Recent results of calculations of the radiation hazard from muon decay neutrinos are presented. This is a significant problem for machines with center of mass energy of 4 TeV, but of no consequence for lower energies. Plans are outlined for future theoretical and experimental studies. Besides continued work on the parameters of a 4 TeV collider, studies are now starting on a machine near 100 GeV that could be a factory for the s-chan… more

Date: May 1, 1997

Creator: Palmer, R. B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Signals from flavor changing scalar currents at the future colliders

We present a general phenomenological analysis of a class of Two Higgs Doublet Models with Flavor Changing Neutral Currents arising at the tree level. The existing constraints mainly affect the couplings of the first two generations of quarks, leaving the possibility for non negligible Flavor Changing couplings of the top quark open. The next generation of lepton and hadron colliders will offer the right environment to study the physics of the top quark and to unravel the presence of new physic… more

Date: November 22, 1996

Creator: Atwood, D.; Reina, L. & Soni, A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Search for high mass photon pairs in p{anti p} collisions at {radical}s = 1.8 TeV

The authors present results of a search for diphoton resonances produced inclusively and in association with a vector boson using 100 pb{sup {minus}1} of p{anti p} collisions using the CDF detector. They set upper limits on the product of cross section times branching ratio for p{anti p} {r_arrow} {gamma}{gamma} {r_arrow} X and p{anti p} {r_arrow} {gamma}{gamma} {r_arrow} W/Z. Using a NLO prediction for associated production cross section of a Higgs with a vector boson (W or Z), they set an upp… more

Date: June 29, 1998

Creator: Wilson, P. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Higgs boson discovery prospects at the Tevatron

Preliminary results from a Fermilab study of the sensitivity for Higgs boson production at the upgraded Tevatron are presented. The study extends previous results by systematically combining results for all decay channels, considering the production of higher mass Higgs bosons and interpreting the results in the context of super-symmetric Higgs production as well as Standard Model production. New analysis methods significantly improve the sensitivity. With 20 fb{sup {minus}1} of accumulated dat… more

Date: May 27, 1999

Creator: Roco, M.T.P. & Grannis, P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

The state of the standard model

The author reviewed the successes of quantum chromodynamics. Then he assessed the current state of the electroweak theory, making brief comments about the search for the Higgs boson and some of the open issues for the theory. He sketches the problems of mass and mass scales, and points to a speculative link between the question of identity and large extra dimensions. To conclude, he returns to QCD and the possibility that its phase structure might inform the understanding of electroweak symmetr… more

Date: January 25, 2000

Creator: Quigg, Chris

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

PDF Uncertainties in WH Production at Tevatron

We apply a method proposed by members of CTEQ Collaboration to estimate the uncertainty in associated W-Higgs boson production at Run II of the Tevatron due to our imprecise knowledge of parton distribution functions. We find that the PDF uncertainties for the signal and background rates are of the order 3%. The PDF uncertainties for the important statistical quantities (significance of the Higgs boson discovery, accuracy of the measurement of the WH cross section) are smaller (1.5%) due to the… more

Date: November 2, 2001

Creator: Sullivan, P. M. Nadolsky and Z.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

The heavy top quark and supersymmetry

Three aspects of supersymmetric theories are discussed: electroweak symmetry breaking, the issues of flavor, and gauge unification. The heavy top quark plays an important, sometimes dominant, role in each case. Additional symmetries lead to extensions of the standard model which can provide an understanding for many of the outstanding problems of particle physics. A broken supersymmetric extension of spacetime allows electroweak symmetry breaking to follow from the dynamics of the heavy top qua… more

Date: May 8, 1996

Creator: Hall, L.J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Higgs Mass Determination From Direct Reconstruction at a Linear E+E- Collider

We study the feasibility of a precise measurement of the mass of a 120 GeV MSM Higgs boson through direct reconstruction of ZH {yields} q{bar q}H events that would be achieved in a future e{sup +}e{sup -} linear collider operating at a center-of-mass energy of 500 GeV. Much effort has been put in a ''realistic simulation'' by including irreducible+reducible backgrounds, realistic detector effects and reconstruction procedures and sophisticated analysis tools involving Neural Networks and kinema… more

Date: December 22, 1999

Creator: Juste, A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Higgs searches and prospects at CDF

The Standard model of electroweak interactions (SM) has been extremely successful in describing interactions of elementary particles over the last decades. The Higgs scalar boson is one of the key elements of the SM: Higgs interactions with the other particles generate the particle masses and allow to keep the theory renormalizable at electroweak scale. All the particles predicted by the SM but the Higgs boson have already been observed experimentally and therefore search for the Higgs is one o… more

Date: January 15, 2003

Creator: Murat, Pavel A

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Search for the Higgs boson produced with $Z \to \ell^+\ell^-$ in $p\bar{p}$ collisions at $\sqrt{s}=$ 1.96 TeV

The authors present a search for the Higgs boson in the process q{bar q} {yields} ZN {yields} {ell}{sup +}{ell}{sup -} b{bar b}. The analysis uses an integrated luminosity of 1 fb{sup -1} of p{bar p} collisions produced at {radical}s = 1.96 TeV and accumulated by the upgraded Collider Detector at Fermilab (CDF II). They employ artificial neural networks both to correct jets mismeasured in the calorimeter, and to distinguish the signal kinematic distributions from those of the background. They s… more

Date: July 1, 2008

Creator: Aaltonen, T.; Phys., /Helsinki Inst. of; Adelman, J.; /Chicago U., EFI; Akimoto, T.; U., /Tsukuba et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

An alternative NMSSM phenomenology with manifest perturbative unification

Can supersymmetric models with a moderate stop mass be made consistent with the negative Higgs boson searches at LEP, while keeping perturbative unification manifest? The NMSSM achieves this rather easily, but only if extra matter multiplets filling complete SU(5) representations are present at intermediate energies. As a concrete example which makes use of this feature, we give an analytic description of the phenomenology of a constrained NMSSM close to a Peccei-Quinn symmetry point. The relat… more

Date: December 18, 2007

Creator: Hall, Lawrence; Barbieri, Riccardo; Pappadopulo, Duccio; Rychkov, Vyacheslav S.; Hall, Lawrence J. & Papaioannou, Anastasios Y.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Contraints on New Physics in MFV models: a model-independent analysis of \DeltaF=1 processes

We analyze the constraints on dimension-six {Delta}F = 1 effective operators in models respecting the MFV hypothesis, both in the one-Higgs doublet case and in the two-Higgs doublet scenario with large tan {beta}. The constraints are derived mainly from the b {yields} s inclusive observables measured at the B factories. The implications of these bounds in view of improved measurements in exclusive and inclusive observables in b {yields} s{ell}{sup +}{ell}{sup -} and s {yields} d{nu}{bar {nu}} t… more

Date: November 5, 2008

Creator: Hurth, Tobias; /SLAC, /CERN; Isidori, Gino; /Pisa, Scuola Normale Superiore /INFN, Pisa /Frascati; Kamenik, Jernej F.; /Frascati /Stefan Inst., Ljubljana et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Universal SU(2/1) and the Higgs and fermion masses

We review the SU(2/1) internal supersymmetry suggested by D. Fairlie and the author in 1979. The initial apparent difficulties were resolved when, with J. Thierry-Mieg, we understood that the gauging of a supergroup implies taking the usual Yang-Mills-like Principal (Double) Fibre Bundle as a ``scaffold`` and using its Grassmann algebra as parameter manifold for the supergauge. SU(2/1) Universality fixes the masses of the Higgs scalar field and the ``top`` quark around 100--200 GeV, in the same… more

Date: December 31, 1992

Creator: Ne`eman, Y.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Search for a Neutral Long-Lived Particle Decaying to B-Jets

The existence of the Higgs boson is required by the Standard Model of particle physics, yet it has not been observed. The precise nature of the Higgs boson is unknown and the mechanism by which it interacts with known Standard Model particles is also not known. Long-lived, electrically neutral hadrons have recently been proposed in hidden-valley models and could constitute a pathway through which the Higgs boson communicates with the Standard Model. Such a scenario may provide a novel path to H… more

Date: April 1, 2009

Creator: Johnson, Chad

Item Type: Thesis or Dissertation

Partner: UNT Libraries Government Documents Department

open access

Search for NMSSM Higgs bosons in the h ---> aa ---> mu mu mu mu, mu mu tau tau channels using p anti-p collisions at s**(1/2) = 1.96-TeV

We report on a first search for production of the lightest neutral CP-even Higgs boson (h) in the next-to-minimal supersymmetric standard model, where h decays to a pair of neutral pseudoscalar Higgs bosons (a), using 4.2 fb{sup -1} of data recorded with the D0 detector at Fermilab. The a bosons are required to either both decay to {mu}{sup +}{mu}{sup -} or one to {mu}{sup +}{mu}{sup -} and the other to {tau}{sup +}{tau}{sup -}. No significant signal is observed, and we set limits on its produc… more

Date: May 1, 2009

Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

A Search for Neutral Supersymmetric Higgs Bosons at D0

A search for Higgs bosons in multijet data from the D0 detector is reported in this thesis. The Higgs boson is the only remaining undiscovered particle in the Standard Model of particle physics, and plays an integral role in this model. It is known that this model is not a complete description of fundamental physics (it does not describe gravity, for example), and so searches for physics beyond the Standard Model are an important part of particle physics. One extension of the Standard Model, th… more

Date: September 1, 2010

Creator: Osman, Nicolas Ahmed

Item Type: Thesis or Dissertation

Partner: UNT Libraries Government Documents Department

open access

A search for the Higgs boson in the zh channel with the D0 detector at the Fermilab Tevatron collider

This analysis describes a search for a standard model Higgs boson produced in association with a Z boson through the decay mode ZH {yields} e{sup +}e{sup -}b{bar b} in p{bar p} collisions at {radical}s = 1.96 TeV at the Fermilab Tevatron Collider. The data sample used in this analysis corresponds to 452 pb{sup -1} of integrated luminosity accumulated with the D{null} detector. Agreement between data and standard model predictions is observed. A 95% confidence level upper exclusion limit for the… more

Date: November 1, 2006

Creator: Heinmiller, James Matthew

Item Type: Thesis or Dissertation

Partner: UNT Libraries Government Documents Department

open access

Double parton interactions as a background to associated HW production at the Tevatron

In this paper we study events with W+jets final state, produced in double parton (DP) interactions, as a background to the associated Higgs boson (H) and W production, with H {yields} b{bar b} decay, at the Tevatron. We have found that the event yield from the DP background can be quite sizable, what necessitates a choice of selection criteria to separate the HW and DP production processes. We suggest a set of variables sensitive to the kinematics of DP and HW events. We show that these variabl… more

Date: November 1, 2010

Creator: Bandurin, Dmitry; Golovanov, Georgy & Skachkov, Nikolai

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Search for higgs, leptoquarks, and exotics at Tevatron

This paper reviews some of the most recent results from the CDF and D0 experiments on the searches for Standard Model and Non-Standard Model Higgs bosons, and other new phenomena at the Tevatron. Both experiments examine data from proton anti-proton collision at {radical}s = 1.96 TeV, of integrated luminosity {approx} 200 pb{sup -1} (per experiment), to search for Higgs predicted in the Standard Model and beyond Standard Model, supersymmetric particles in the Gauge Mediated Symmetry Breaking sc… more

Date: June 22, 2004

Creator: Wang, Song Ming

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

New results for a photon-photon collider

We present new results from studies in progress on physics at a two-photon collider. We report on the sensitivity to top squark parameters of MSSM Higgs boson production in two-photon collisions; Higgs boson decay to two photons; radion production in models of warped extra dimensions; chargino pair production; sensitivity to the trilinear Higgs boson coupling; charged Higgs boson pair production; and we discuss the backgrounds produced by resolved photon-photon interactions.

Date: September 26, 2002

Creator: al., David Asner et

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Present and future electroweak precision measurements and the indirect determination of the mass of the Higgs boson

We discuss the experimental and theoretical uncertainties on precision electroweak observables and their relationship to the indirect constraints on the Higgs boson mass, MH, in the Standard Model (SM). The critical experimental measurements (M{sub W}, sin{sup 2}{theta}{sub eff}, m{sub t},...) are evaluated in terms of their present uncertainties and their prospects for improved precision at future colliders, and their contribution to the constraints on MH. In addition, the current uncertaintie… more

Date: February 14, 2002

Creator: al., U. Baur et

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Physics at a photon collider

A Photon Collider will provide unique opportunities to study the SM Higgs boson and to determine its properties. MSSM Higgs bosons can be discovered at the Photon Collider for scenarios where they might escape detection at the LHC. As an example for the many other physics topics which can be studied at a Photon Collider, recent results on Non-Commutative Field Theories are also discussed.

Date: September 30, 2002

Creator: Soldner-Rembold, Stefan

Item Type: Article

Partner: UNT Libraries Government Documents Department