Search results for "Higgs"
showing 10 items of 1127 documents
Sensitivity to the Higgs sector of SUSY-seesaw models via LFV tau decays
2009
4 páginas, 3 figuras.-- PACS: 11.30.Hv, 12.60.Jv, 14.60.St.-- El PDF es la versión pre-print (arXiv:0909.0724v1).-- Trabajo presentado en la 7th International Conference on Supersymmetry and the Unification of Fundamental Interactions (SUSY09).
Search for the standard model Higgs boson in tau final states
2009
We present a search for the standard model Higgs boson using hadronically decaying tau leptons, in 1 inverse femtobarn of data collected with the D0 detector at the Fermilab Tevatron ppbar collider. We select two final states: tau plus missing transverse energy and b jets, and tau+ tau- plus jets. These final states are sensitive to a combination of associated W/Z boson plus Higgs boson, vector boson fusion and gluon-gluon fusion production processes. The observed ratio of the combined limit on the Higgs production cross section at the 95% C.L. to the standard model expectation is 29 for a Higgs boson mass of 115 GeV.
Combined Search for the Standard Model Higgs Boson Decaying tobb¯Using the D0 Run II Data Set
2012
We present the results of the combination of searches for the standard model Higgs boson produced in association with a W or Z boson and decaying into b bbar using the data sample collected with the D0 detector in p pbar collisions at sqrt{s}=1.96 TeV at the Fermilab Tevatron Collider. We derive 95% CL upper limits on the Higgs boson cross section relative to the standard model prediction in the mass range 100 GeV <= M_H <= 150 GeV, and we exclude Higgs bosons with masses smaller than 102 GeV at the 95% CL. In the mass range 120 GeV <= M_H <= 145 GeV the data exhibit an excess above the background prediction with a global significance of 1.5 standard deviations, consistent with the expectat…
Search for a Fermiophobic and Standard Model Higgs Boson in Diphoton Final States
2011
Made available in DSpace on 2022-04-29T01:13:49Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-10-05 National Science Foundation We present a search for the standard model Higgs boson and a fermiophobic Higgs boson in the diphoton final states based on 8.2fb-1 of pp̄ collisions at √s=1.96TeV collected with the D0 detector at the Fermilab Tevatron Collider. No excess of data above background predictions is observed and upper limits at the 95% C.L. on the cross section multiplied by the branching fraction are set which are the most restrictive to date. A fermiophobic Higgs boson with a mass below 112.9 GeV is excluded at the 95% C.L. © 2011 American Physical Society. Universidad de Bu…
Search for higgs bosons decaying to tau pairs in pp̄ collisions with the D0 detector
2008
Made available in DSpace on 2022-04-28T20:43:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-08-14 Science and Technology Facilities Council We present a search for the production of neutral Higgs bosons decaying into τ+τ- final states in pp̄ collisions at a center-of-mass energy of 1.96 TeV. The data, corresponding to an integrated luminosity of approximately 1fb-1, were collected by the D0 experiment at the Fermilab Tevatron Collider. Limits on the production cross section times branching ratio are set. The results are interpreted in the minimal supersymmetric standard model yielding limits that are the most stringent to date at hadron colliders. © 2008 The American Physical Soc…
Search for the charged lepton flavor violating decay J/ψ→eτ
2021
A search for the charged lepton flavor violating decay J/ψ→e±τ∓ with τ∓→π∓π0ντ is performed with about 10×109 J/ψ events collected with the BESIII detector at the BEPCII. No significant signal is observed, and an upper limit is set on the branching fraction B(J/ψ→e±τ∓)<7.5×10−8 at the 90% confidence level. This improves the previously published limit by two orders of magnitude.
Integrating out resonances in strongly-coupled electroweak scenarios
2016
Accepting that there is a mass gap above the electroweak scale, the Electroweak Effective Theory (EWET) is an appropriate tool to describe this situation. Since the EWET couplings contain information on the unknown high-energy dynamics, we consider a generic strongly-coupled scenario of electroweak symmetry breaking, where the known particle fields are coupled to heavier states. Then, and by integrating out these heavy fields, we study the tracks of the lightest resonances into the couplings. The determination of the low-energy couplings (LECs) in terms of resonance parameters can be made more precise by considering a proper short-distance behaviour on the Lagrangian with heavy states, sinc…
Search for Resonant Pair Production of Neutral Long-Lived Particles Decaying tobb¯inpp¯Collisions ats=1.96 TeV
2009
We report on a first search for resonant pair production of neutral long-lived particles (NLLP) which each decay to a b (b) over bar pair, using 3.6 fb(-1) of data recorded with the D0 detector at the Fermilab Tevatron collider. We search for pairs of displaced vertices in the tracking detector at radii in the range 1.6-20 cm from the beam axis. No significant excess is observed above background, and upper limits are set on the production rate in a hidden-valley benchmark model for a range of Higgs boson masses and NLLP masses and lifetimes.
Higgs-boson radiative corrections to the decayS13(QQ¯)→Hγ
1988
We consider one-loop radiative corrections to the Wilczek mechanism (/sup 3/S/sub 1/(QQ-bar)..-->..H..gamma..) due to a subset of the electroweak theory, the Higgs sector, in the standard model and discuss extensions to two-Higgs-doublet models. We discuss the circumstances under which such corrections can be important.
Electroweak baryogenesis and dark matter from a singlet Higgs
2012
If the Higgs boson H couples to a singlet scalar S via lambda_m |H|^2 S^2, a strong electroweak phase transition can be induced through a large potential barrier that exists already at zero temperature. In this case properties of the phase transition can be computed analytically. We show that electroweak baryogenesis can be achieved using CP violation from a dimension-6 operator that couples S to the top-quark mass, suppressed by a new physics scale that can be well above 1 TeV. Moreover the singlet is a dark matter candidate whose relic density is < 3% of the total dark matter density, but which nevertheless interacts strongly enough with nuclei (through Higgs exchange) to be just below…