116951518
Finiteness in Conventional N = 1 Guts
Finite Unified Theories (FUTs) are N = 1 supersymmetric GUT’s which have the remarkable feature of being all-loop finite beyond the unification point. They also have impressive predictive power. We present here a review of the recent developments of the softly broken sector of N = 1 FUTs. The new characteristic predictions of FUTs are: 1) The lightest Higgs boson mass is predicted to be in the window 120-130 GeV, in case the LSP is neutralino, while in case the LSP is the \( \tilde{\tau } \) (which can be consistently accommodated in presence of bilinear R-parity violating terms) it can be as light as 111 GeV. 2) The s-spectrum starts above several hundreds of GeV.
121745688
Conditions for vacuum stability in an S3 extension of the Standard Model
In this work we study the Higgs sector in the minimal S3 extension of the Standard Model. The S3 extended Standard Model, which has three Higgs doublets fields that belong to the three-dimensional reducible representation of the permutation group S3, has naturally new phenomena: there are several Higgs bosons, charged, neutral and pseuodscalar ones, and more than one potential minimum. We analyzed the stability of the minimal S3 invariant extension of the Higgs potential and show that at tree-level, the potential minimum preserving electric charge and CP symmetries, when it exists, is the global one.
121936366
Finite unified theories and the top quark mass
We present results of a study of two phenomenologically interesting SU (5) supersymmetric Grand Unified models, which are finite to all-loops before spontaneous symmetry breaking. The finiteness conditions provide us with relationships among the Yukawa and gauge couplings at the unification point, which in turn predict a heavy top quark mass (∼ 175 – 190 GeV).
125202226
Finite unification at all-loops
12010699
Top quark mass predictions from gauge Yukawa unification
Gauge-Yukawa Unification (GYU) is a renormalization group invariant functional relation among gauge and Yukawa couplings which holds beyond the unification point in Grand Unified Theories (GUTs). Here, GYU is obtained by requiring finiteness and reduction of couplings to all orders in perturbation theory. We examine the consequences of GYU in various supersymmetric GUTs and in particular the predictions for the top quark mass. These predictions are such that they distinguish already GYU from ordinary GUTs. Moreover, when more accurate measurements of the top quark mass are available, it is expected that it will be possible to discriminate among the various GYUs.
120143394
Finite GUTs within conventional N=1 gauge theories
Finite Unified Theories (FUTs) are conventional N=1 supersymmetric Grand Unified Theories, which can be made all-loop finite, both in the dimensionless (gauge and Yukawa couplings) and dimensionful (soft supersymmetry breaking terms) sectors. This remarkable property leads to a drastic reduction in the number of free parameters, which in turn leads to an accurate prediction of the top quark mass in the dimensionless sector, and predictions for the Higgs boson mass and the s-spectrum in the dimensionful sector. Among the characteristics of the latter ones are: 1) The lightest Higgs boson mass is predicted to be in the window 120–130 GeV, in case the LSP is neutralino, while in case the LSP is the τ (which can be consistently accommodated in presence of bilinear R-parity violating terms) it can be as light as 111 GeV. 2) The s-spectrum starts above several hundreds of GeV.
209835699
Search for anomalous production of events with two photons and additional energetic objects at CDF
We present results of a search for anomalous production of two photons together with an electron, muon, τ lepton, missing transverse energy, or jets using pp collision data from 1.1–2.0  fb-1 of integrated luminosity collected by the Collider Detector at Fermilab (CDF). The event yields and kinematic distributions are examined for signs of new physics without favoring a specific model of new physics. The results are consistent with the standard model expectations. The search employs several new analysis techniques that significantly reduce instrumental backgrounds in channels with an electron and missing transverse energy.
8753620
Search for the standard model Higgs boson decaying to a bb pair in events with one charged lepton and large missing transverse energy using the full CDF data set.
We present a search for the standard model Higgs boson produced in association with a W boson in sqrt[s]=1.96  TeV pp collision data collected with the CDF II detector at the Tevatron corresponding to an integrated luminosity of 9.45  fb(-1). In events consistent with the decay of the Higgs boson to a bottom-quark pair and the W boson to an electron or muon and a neutrino, we set 95% credibility level upper limits on the WH production cross section times the H→bb branching ratio as a function of Higgs boson mass. At a Higgs boson mass of 125  GeV/c(2), we observe (expect) a limit of 4.9 (2.8) times the standard model value.
17564718
Top quark mass measurement in the lepton + jets channel using a matrix element method and in situ jet energy calibration.
A precision measurement of the top quark mass m(t) is obtained using a sample of tt events from pp collisions at the Fermilab Tevatron with the CDF II detector. Selected events require an electron or muon, large missing transverse energy, and exactly four high-energy jets, at least one of which is tagged as coming from a b quark. A likelihood is calculated using a matrix element method with quasi-Monte Carlo integration taking into account finite detector resolution and jet mass effects. The event likelihood is a function of m(t) and a parameter Δ(JES) used to calibrate the jet energy scale in situ. Using a total of 1087 events in 5.6 fb(-1) of integrated luminosity, a value of m(t)=173.0 ± 1.2 GeV/c(2) is measured.