1,720,975 research outputs found
Probing light charged Higgs bosons in the 2-Higgs doublet model Type-II with vector-like quarks
No full textWe show how the presence of Vector-Like Quarks (VLQs) with quantum numbers identical to the top-quark ones alongside a Type-II 2-Higgs Doublet Model (2HDM-II) (pseudo)scalar sector can remove the stringent constraint on the mass of the charged Higgs boson H± (of some 580 GeV) emerging in such a scenario from B-physics results. We prove this to be the case for two representations of such VLQs, both a singlet and a doublet one, wherein the the lowest allowed mH± value can be 80 GeV. This is due to cancellations onsetting in b→sγ topologies between VLQ and H± contributions. Furthermore, in order to enable one to probe the regions of, as it were, this `2HDM-II+VLQ' parameter space where this mechanism is most effective, we present several results on production cross sections and decay rates involving a top-quark companion (T) with VLQ nature and the 2HDM-II Higgs bosons, chiefly the H± state, which can then guide the search for both extended Higgs and quark sectors at the Large Hadron Collider (LHC) at CERN. Specifically, we highlight the case of VLQ pair production pp→TT¯ followed by T→H±b decays, where the H± state may in turn decay into τν or tb pairs, depending on whether mH±<mt or mH±>mt, respectively
Superposition of CP-Even and CP-Odd Higgs resonances: explaining the 95 GeV excesses within a Two-Higgs Doublet Model
No full textWe propose an explanation for the observed excesses around 95 GeV in the di-photon and di-tau invariant mass distributions, as reported by the CMS collaboration at the Large Hadron Collider (LHC). These findings are complemented by a long-standing discrepancy in the bb¯ invariant mass at the Large Electron-Positron (LEP) Collider. Additionally, the ATLAS collaboration has reported a corroborative excess in the di-photon final state within the same mass range, albeit with slightly lower significance. Our approach involves the superposition of CP-even and CP-odd Higgs bosons within the Type-III Two-Higgs Doublet Model (2HDM) to simultaneously explain these excesses at 1σ Confidence Level (C.L.), while remaining consistent with current theoretical and experimental constraints
Large Hadron Collider signatures of exotic Vector-Like quarks within the 2-Higgs Doublet Model Type-II
No full textWe study the decay of the exotic Vector-Like Quarks (VLQs) X and Y, with 5/3 and −4/3 units of electric charge, respectively, within the 2-Higgs Doublet Model (2HDM). Building on our previous studies of Vector-Like Top and Bottom (VLT and VLB) quarks, we now investigate the characteristics of X and Y in the alignment limit of a Type-II Yukawa structure and show that, in the framework of such a 2HDM, one can have large non-Standard Model (SM) decay rates of the X andY states. Our analysis focuses on their potential detection at the Large Hadron Collider (LHC), based on their pair production followed by a variety of both SM and non-SM decay patterns. In order to distinguish between doublet and triplet representations of the VLQs X and Y, we uncover specific signatures that can provide insights into this particular architecture of Beyond the SM (BSM) physics
Anatomy of Vector-Like Bottom-Quark Models in the alignment limit of the 2-Higgs Doublet Model Type-II
No full textExpanding upon our ongoing investigation of Vector-Like Quark (VLQ) phenomenology within a 2-Higgs Doublet Model (2HDM) framework, in this paper, we complement a previous one dedicated to Vector-Like Top-quarks (VLTs) by studying Vector-Like Bottom-quarks (VLBs), specifically focusing on their behavior in the alignment limit of a Type-II Yukawa structure. We examine the potential for detecting VLBs at the Large Hadron Collider (LHC) and analyze their decay signatures, encompassing both Standard Model (SM) processes and exotic decays. The objective is to differentiate among singlet, doublet, and triplet configurations of VLBs by identifying distinct decay patterns, thereby providing insights into the structure of Beyond the SM (BSM) physics
Probing a 96 GeV Higgs Boson in the Di-Photon Channel at the LHC
Get PDFRecently the CMS collaboration reported a local excess in the
di-photon spectrum at 96 GeV. The same mass range concurs with a
local excess in the invariant mass spectrum in four-jet events
collected at LEP. In this contribution we show that at 1 level the 2HDM
type-III can perfectly fit both excesses simultaneously, while satisfying all
experimental and theoretical constraints.Comment: 6 pages, 2 figures, contribution to the proceedings of the 41st
International Conference on High Energy physics - ICHEP202
Explaining the 96 GeV Di-photon anomaly in a generic 2HDM Type-III
No full textMotivated by results recently reported by the CMS Collaboration about an excess in the di-photon spectrum at about 96 GeV, especially when combined with another long-standing anomaly at the same value in the bb¯ invariant mass spectrum in four-jet events collected at LEP, we show that a possible explanation to both phenomena can be found at 1σ level in a generic 2-Higgs Doublet Model (2HDM) of Type-III in presence of a specific Yukawa texture, wherein Lepton Flavour Violating (LFV) (neutral) currents are induced at tree level. Bounds from Higgs data play a major role in limiting the parameter space of this scenario, yet we find solutions with m
H=125 GeV and m
h=96 GeV consistent with current theoretical and experimental bounds.
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Vector-like quarks at the LHC: a unified perspective from ATLAS and CMS exclusion limits
No full textIn this work, we present a comprehensive review of the most up-to-date exclusion limits on Vector-Like Quarks (VLQs) derived from ATLAS and CMS data at the Large Hadron Collider (LHC). Our analysis encompasses both pair and single production modes, systematically comparing results from the two collaborations to identify and employ the most stringent bounds at each mass point. We evaluate the excluded parameter space for VLQs under singlet, doublet, and triplet representations. For top-like VLQs (T), the exclusion limits rule out masses up to 1.49 TeV in singlet scenarios, while single production constrains the mixing parameter κ to values below 0.26 at mT∼1.5 TeV and up to 0.42 for mT∼2 TeV. For bottom-like VLQs (B), the strongest exclusion limits from pair production exclude masses up to 1.52 TeV in doublet configurations, with single production constraining κ values between 0.2 and 0.7 depending on the mass. For exotic VLQs, such as X and Y, pair production excludes masses up to 1.46 TeV and 1.7 TeV, respectively. The constraints on κ from these analyses become increasingly restrictive at higher masses, reflecting the enhanced sensitivity of single production channels in this regime. For X, κ is constrained below 0.16 for masses between 0.8 and 1.6 TeV and further tightens to κ<0.2 as the mass approaches 1.8 TeV. Similarly, for Y, κ values are constrained below 0.26 around mY∼1.7 TeV, with exclusions gradually relaxing at higher masses. These exclusion regions, derived from the most stringent LHC search results, offer a unified and up-to-date perspective on VLQ phenomenology. The results were computed using \texttt{VLQBounds}, a new Python-based tool specifically developed for this purpose
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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