Using triangulation to identify word senses

Word sense disambiguation is the task of determining which sense of a word is intended from its context. Previous methods have found the lack of training data and the restrictiveness of dictionaries' choices of senses to be major stumbling blocks. A robust novel algorithm is presented that uses multiple dictionaries, the Internet, clustering and triangulation to attempt to discern the most useful senses of a given word and learn how they can be disambiguated. The algorithm is explained, and some promising sample results are given

Lepton Number Violation and W' Chiral Couplings at the LHC

We study the observability for a heavy Majorana neutrino N along with a new charged gauge boson W' at the LHC. We emphasize the complementarity of these two particles in their production and decay to unambiguously determine their properties. We show that the Majorana nature of N can be verified by the lepton-number violating like-sign dilepton process, and by polar and azimuthal angular distributions. The chirality of the W' coupling to leptons and to quarks can be determined by a polar angle distribution in the reconstructed frame and an azimuthal angle distribution.Comment: 44 pages, 17 Figures; v2 journal versio

Sleptons without Hadrons

Multilepton searches for electroweakino and slepton pair production at hadron colliders remain some of the best means to test weak-scale supersymmetry. Searches at the CERN Large Hadron Collider, however, are limited by large diboson and top quark pair backgrounds, despite the application of traditional, central jet vetoes. In this context, we report the impact of introducing dynamic jet vetoes in searches for colorless superpartners. As a representative scenario, we consider the Drell-Yan production of a pair of right-handed smuons decaying into a dimuon system accompanied with missing transverse energy. As an exploratory step, we consider several global and local measures of the leptonic and hadronic activity to construct the veto. In most all cases, we find that employing a dynamic jet veto improves the sensitivity, independently of the integrated luminosity. The inclusion of non-perturbative multiple particle interactions and next-to-leading order jet merging does not alter this picture. Directions for further improvements are discussed.Comment: 18 pages; 7 figures; additional discussions added; journal version; results unchange

Unresolved Issue in Education: Disproportionate Disciplining of Hispanic Students in Education

The disproportionate disciplining of Hispanic students has been a reoccurring issue that has persisted for decades. With the rising Hispanic populations nationwide and in the state of California, this issue must be addressed. Therefore, to contribute to the scholarship of this phenomenon, the author critically examined teacher and administrator perceptions and attitudes about students who embody a stereotypical urban street subculture. The purpose of this convergent parallel mixed-methods study was to examine the interplay of race, cultural capital, community, and communication, with the disproportionate disciplining of Hispanic students in schools where they are a minority population. The findings of this study expose many unconscious biases and internalized stereotypes that are not openly discussed, yet have a profound impact on a Hispanic student’s educational outcomes. Recommendations include teacher preparation programs that address unspoken biases, social-emotional and cultural competency training, and community outreach programs for the schools that were studied

Lepton number violation at colliders from kinematically inaccessible gauge bosons

We reevaluate the necessity of WRWR gauge bosons being kinematically accessible to test the left–right symmetric model (LRSM) at hadron colliders. In the limit that WRWR are too heavy, resonant production of sub-TeV Majorana neutrinos N can still proceed at the Large Hadron Collider (LHC) via the process pp→W±∗R→Nℓ±→ℓ±ℓ±+njpp→WR±∗→Nℓ±→ℓ±ℓ±+nj if mediated by a far off-shell WRWR . Traditional searches strategies are insensitive to this regime as they rely on momenta of final states scaling with TeV-scale MWRMWR . For such situations, the process is actually kinematically and topologically identical to the direct production (DP) process pp→W±∗SM→Nℓ±→ℓ±ℓ±+njpp→WSM±∗→Nℓ±→ℓ±ℓ±+nj . In this context, we reinterpret s√=8s=8 TeV LHC constraints on DP rates for the minimal LRSM. For mN=mN= 200–500 GeV and right–left coupling ratio κR=gR/gLκR=gR/gL , we find (MWR/κR)>(MWR/κR)> 1.1–1.8 TeV at 95% CLs. Expected sensitivities to DP at 14 (100) TeV are also recast: with L=1 (10)L=1 (10) ab −1−1 , one can probe (MWR/κR)<(MWR/κR)< 7.9–8.9 (14–40) TeV for mN=mN= 100–700 (1200) GeV, well beyond the anticipated sensitivity of resonant WRWR searches. Findings in terms of gauge invariant dimension-six operators with heavy N are also reported

Doubly Charged Higgs Boson Production at Hadron Colliders II: A Zee-Babu Case Study

Motivated by searches for so-called leptonic scalars at the LHC and the recent measurement of the $W$ boson's mass at the Tevatron, we revisit the phenomenology of the Zee-Babu model for neutrino masses and the ability to differentiate it from the Type II Seesaw model at the LHC. We conclude that this task is much more difficult than previously believed. All inputs equal in the two scenarios, we find that total and differential rates for producing pairs of doubly and singly charged scalars are identical in shape and only differ in normalization. The normalization is given by the ratio of hadronic cross sections and can be unity. Differences in cross sections are small and can be hidden by unknown branching rates. This holds for Drell-Yan, $\gamma\gamma$ fusion, and $gg$ fusion, as well as observables at LO and NLO in QCD. This likeness allows us to reinterpret Run II limits on the Type II Seesaw and estimate projections for the HL-LHC. Using updated neutrino oscillation data, we also find that some collider observables, e.g., lepton flavor-violating branching ratios, are now sufficiently precise to provide a path forward. Other means of discrimination are also discussed. As a byproduct of this work, we report the availability of new Universal \texttt{FeynRules} Object libraries, the \texttt{SM\_ZeeBabu} UFO, that enable fully differential simulations up to NLO+LL(PS) with tool chains employing \texttt{MadGraph5\_aMC@NLO}.Comment: Journal version: add'l discussions on low-energy connections, results unchanged. 51 pages (total), including appendices (6 pages), 11 tables, and 9 figures. New UFO available from FeynRules database https://feynrules.irmp.ucl.ac.be/wiki/ZeeBabu and analysis code available from gitlab https://gitlab.cern.ch/riruiz/public-projects/-/tree/master/ZeeBabu_LHC_Update Happy Fall

Hadron Collider Tests of Neutrino Mass-Generating Mechanisms

The Standard Model of particle physics (SM) is presently the best description of nature at small distances and high energies. However, with tiny but nonzero neutrino masses, a Higgs boson mass unstable under radiative corrections, and little guidance on understanding the hierarchy of fermion masses, the SM remains an unsatisfactory description of nature. Well-motivated scenarios that resolve these issues exist but also predict extended gauge (e.g., Left-Right Symmetric Models), scalar (e.g., Supersymmetry), and/or fermion sectors (e.g., Seesaw Models). Hence, discovering such new states would have far-reaching implications. After reviewing basic tenets of the SM and collider physics, several beyond the SM (BSM) scenarios that alleviate these shortcomings are investigated. Emphasis is placed on the production of a heavy Majorana neutrinos at hadron colliders in the context of low-energy, effective theories that simultaneously explain the origin of neutrino masses and their smallness compared to other elementary fermions, the so-called Seesaw Mechanisms. As probes of new physics, rare top quark decays to Higgs bosons in the context of the SM, the Types I and II Two Higgs Doublet Model (2HDM), and the semi-model independent framework of Effective Field Theory (EFT) have also been investigated. Observation prospects and discovery potentials of these models at current and future collider experiments are quantified.Comment: PhD thesis. University of Pittsburgh, April 2015. 220 pages total, 48 figures. Based on arXiv submissions 1211.6447, 1312.3324, and 1411.7305 with expanded discussion on collider physic