Search results for "HIGGS-BOSON"
showing 10 items of 10 documents
Supersymmetric SO(10)-inspired GUTs with sliding scales
2013
We construct lists of supersymmetric models with extended gauge groups at intermediate steps, all of which are inspired by SO(10) unification. We consider three different kinds of setups: (i) the model has exactly one additional intermediate scale with a left-right (LR) symmetric group; (ii) SO(10) is broken to the LR group via an intermediate Pati-Salam scale; and (iii) the LR group is broken into SU(3)(c) X SU(2)(L) X U(1)(R) X U(1)(B-L), before breaking to the standard model (SM) group. We use sets of conditions, which we call the "sliding mechanism," which yield unification with the extended gauge group(s) allowed at arbitrary intermediate energy scales. All models thus can have new gau…
A new observable to measure the top-quark mass at hadron colliders
2013
A new method to measure the top-quark mass in high energetic hadron collisions is presented. We use theoretical predictions calculated at next-to-leading order accuracy in quantum chromodynamics to study the ( normalized) differential distribution of the t (t) over bar + 1-jet cross section with respect to its invariant mass root s(t (t) over barj). The sensitivity of the method to the top-quark mass together with the impact of various theoretical and experimental uncertainties has been investigated and quantified. The new method allows for a complementary measurement of the top-quark mass parameter and has a high potential to become competitive in precision with respect to established appr…
Evidence for a Particle Produced in Association with Weak Bosons and Decaying to a Bottom-Antibottom Quark Pair in Higgs Boson Searches at the Tevatr…
2012
Aaltonen, T. et al.
Review of Particle Physics
2020
The Review summarizes much of particle physics and cosmology. Using data from previous editions, plus 2,143 new measurements from 709 papers, we list, evaluate, and average measured properties of gauge bosons and the recently discovered Higgs boson, leptons, quarks, mesons, and baryons. We summarize searches for hypothetical particles such as supersymmetric particles, heavy bosons, axions, dark photons, etc. Particle properties and search limits are listed in Summary Tables. We give numerous tables, figures, formulae, and reviews of topics such as Higgs Boson Physics, Supersymmetry, Grand Unified Theories, Neutrino Mixing, Dark Energy, Dark Matter, Cosmology, Particle Detectors, Colliders, …
Long-lived particles at the energy frontier: the MATHUSLA physics case
2019
We examine the theoretical motivations for long-lived particle (LLP) signals at the LHC in a comprehensive survey of Standard Model (SM) extensions. LLPs are a common prediction of a wide range of theories that address unsolved fundamental mysteries such as naturalness, dark matter, baryogenesis and neutrino masses, and represent a natural and generic possibility for physics beyond the SM (BSM). In most cases the LLP lifetime can be treated as a free parameter from the $\mu$m scale up to the Big Bang Nucleosynthesis limit of $\sim 10^7$m. Neutral LLPs with lifetimes above $\sim$ 100m are particularly difficult to probe, as the sensitivity of the LHC main detectors is limited by challenging …
Measuring anomalous couplings in H -> WW* decays at the International Linear Collider
2010
The measurement of the Higgs coupling to W bosons is an important test of our understanding of the electroweak symmetry-breaking mechanism. We study the sensitivity of the International Linear Collider (ILC) to the presence of anomalous HW+W- couplings using ZH -> nu(nu) over bar WW* -> nu(nu) over bar 4j events. Using an effective Lagrangian approach, we calculate the differential decay rates of the Higgs boson including the effects of new dimension-five operators. We present a Monte Carlo simulation of events at the ILC, using a full detector simulation based on GEANT4 and a real event reconstruction chain. Expected constraints on the anomalous couplings are given.
Tevatron Combination of Single-Top-Quark Cross Sections and Determination of the Magnitude of the Cabibbo-Kobayashi-Maskawa Matrix Element Vtb
2015
et al.
Supersymmetric type-III seesaw mechanism: Lepton flavor violation and LHC phenomenology
2013
We study a supersymmetric version of the type-III seesaw mechanism considering two variants of the model: a minimal version for explaining neutrino data with only two copies of 24 superfields and a model with three generations of 24-plets. The latter predicts, in general, rates for mu -> e gamma inconsistent with experimental data. However, this bound can be evaded if certain special conditions within the neutrino sector are fulfilled. In the case of two 24-plets, lepton flavor violation constraints can be satisfied much more easily. After specifying the corresponding regions in the minimal supergravity parameter space, we show that under favorable conditions one can test the corresponding …
Precise measurement of the top quark mass in dilepton decays using optimized neutrino weighting
2016
We measure the top quark mass in dilepton final states of top-antitop events in proton-antiproton collisions at sqrt(s) = 1.96 TeV, using data corresponding to an integrated luminosity of 9.7 fb^-1 at the Fermilab Tevatron Collider. The analysis features a comprehensive optimization of the neutrino weighting method to minimize the statistical uncertainties. We also improve the calibration of jet energies using the calibration determined in top-antitop to lepton+jets events, which reduces the otherwise limiting systematic uncertainty from the jet energy scale. The measured top quark mass is mt = 173.32 +/- 1.36(stat) +/- 0.85(syst) GeV.
The Hunt for New Physics at the Large Hadron Collider
2010
233 páginas.-- AHEP Group: et al..-- El Pdf del artículo es la versión pre-print: arXiv.1001.2693v1.-- Trabajo presentado al "The International Workshop on Beyond the Standard Model Physics and LHC Signatures (BSM-LHC) celebrado en Boston (USA) del 2 al 4 de junio de 2009.