2.6k citations
Counting papers with at most 25 authors, so collaboration author lists do not stand in for the people here.
- Instituto Superior TécnicoPT201 papers
- University of LisbonPT82 papers
- Universidade Técnica de LisboaPT54 papers
- Universitat de ValènciaES44 papers
- Instituto Politécnico de LisboaPT30 papers
- Instituto de Física CorpuscularES16 papers
- Thomas Jefferson National Accelerator FacilityUS15 papers
- European Organization for Nuclear ResearchCH13 papers
- Centre National de la Recherche ScientifiqueFR12 papers
- Consejo Superior de Investigaciones CientíficasES10 papers
- Centro de Física Teórica e Computacional9 papers
- University of ÉvoraPT9 papers
219 papers
Exploiting exotic LHC datasets for long-lived new particle searches
Hesham El Faham, Andrea Giammanco, Jan Hajer
Motivated by the expectation that new physics may manifest itself in the form of very heavy new particles, most of the operation time of the LHC is devoted to collisions at th…
Beyond lepton number violation at the HL-LHC: Resolving heavy neutrino-antineutrino oscillations
Stefan Antusch, Jan Hajer, Johannes Rosskopp
Collider testable low-scale seesaw models predict pseudo-Dirac heavy neutrinos, that can produce an oscillating pattern of lepton number conserving and lepton number violating even…
CP-odd and CP-even Weak-Basis Invariants in the Presence of Vector-Like Quarks
Francisco Albergaria, G. C. Branco, José Filipe Bastos +1
We propose a minimal set of weak-basis invariants in an extension of the SM where one up-type isosinglet vector-like quark is introduced, which allows us to obtain all the physical…
Simulating lepton number violation induced by heavy neutrino-antineutrino oscillations at colliders
Stefan Antusch, Jan Hajer, Johannes Rosskopp
We study pseudo-Dirac pairs of two almost mass-degenerate sterile Majorana neutrinos which generate light neutrino masses via a low-scale seesaw mechanism. These pseudo-Dirac heavy…
Axionic Dirac seesaw and electroweak vacuum stability
J. T. Penedo, Yakefu Reyimuaji, Xinyi Zhang
We explore the connection between tree-level Dirac neutrino masses and axion physics in a scenario where the PQ symmetry enforces lepton number conservation perturbatively. Requiri…
Do the Small Numbers in the Quark Mixing arise from New Physics?
G. C. Branco, José Filipe Bastos, J. I. Silva-Marcos
We put forward the conjecture that the small numbers in the matrix, are generated by physics beyond the Standard Model. We identify as small numbers and the…
Dark matter in a CP-violating three-Higgs-doublet model with symmetry
A. Kunčinas, O. M. Ogreid, P. Osland +1
In spite of the success of the Standard Model of Particle Physics, there are some theoretical predictions which are not yet fully established experimentally as well as some experim…
3HDM with symmetry and its phenomenological consequences
J. Kalinowski, W. Kotlarski, M. N. Rebelo +1
We perform a comprehensive analysis of a version of the 3-Higgs doublet model whose scalar potential is invariant under a global discrete symmetry and where the three scala…
Decays of the Heavy Top and New Insights on in a one-VLQ Minimal Solution to the CKM Unitarity Problem
Francisco J. Botella, G. C. Branco, M. N. Rebelo +2
We propose a minimal extension of the Standard Model where an up-type vector-like quark, denoted , is introduced and provides a simple solution to the CKM unitarity problem. We…
Dark matter in three-Higgs-doublet models with symmetry
W. Khater, A. Kunčinas, O. M. Ogreid +2
Models with two or more scalar doublets with discrete or global symmetries can have vacua with vanishing vacuum expectation values in the bases where symmetries are imposed. If a s…
Diluting quark flavor hierarchies using dihedral symmetry
Ayushi Srivastava, Miguel Levy, Dipankar Das
We present a flavored extension of the SM which provides an intuitive reasoning for the masses and mixing patterns in the quark sector. In our model, the Cabibbo mixing angle…
Prospects of light charged scalars in a three Higgs doublet model with symmetry
Manimala Chakraborti, Dipankar Das, Miguel Levy +2
The stringent constraints from the direct searches for exotic scalars at the LHC as well as indirect bounds from flavor physics measurements have imposed severe restrictions on the…
Addressing the CKM Unitarity Problem with a Vector-like Up Quark
G. C. Branco, J. T. Penedo, Pedro M. F. Pereira +2
We point out that hints of deviations from unitarity in the first row of the CKM matrix may be explained by the presence of a single vector-like top. We study how the stringent exp…
Leaks of CP violation in the real two-Higgs doublet model
Duarte Fontes, Maximilian Löschner, Jorge C. Romão +1
We discuss the symmetric two Higgs doublet model with a real soft breaking term (real 2HDM). We explain in detail why it is not tenable to assume CP conservation in the scala…
Warm Inflation, Neutrinos and Dark matter: a minimal extension of the Standard Model
Miguel Levy, João G. Rosa, Luis B. Ventura
We show that warm inflation can be realized within a minimal extension of the Standard Model with three right-handed neutrinos, three complex scalars and a gauged lepton/B-L U(1) s…
Yet another lesson on the stability conditions in multi-Higgs potentials
Igor P. Ivanov, Francisco Vazão
We discuss a rather common but often unnoticed pitfall which arises when deriving the bounded-from-below (BFB) conditions in multi-Higgs models with softly broken global symmetries…
Crossed two Higgs-doublet models: reduction of Yukawa parameters in the low-scale limit of left-right symmetry and other avatars
Gustavo C. Branco, Dipankar Das, Miguel Levy +1
We present new variants of the Two Higgs-Doublet Model where all Yukawa couplings with physical Higgs bosons are controlled by the quark mixing matrices of both chiralities, as wel…
Nondecoupling in Multi-Higgs doublet models
Francisco Faro, Jorge C. Romao, Joao P. Silva
We consider models with any number of Higgs doublets and study the conditions for decoupling. We show that, under very general circumstances, all the quadratic coefficients of the…
Type-I Seesaw with eV-Scale Neutrinos
G. C. Branco, J. T. Penedo, Pedro M. F. Pereira +2
We consider seesaw type-I models including at least one (mostly-)sterile neutrino with mass at the eV scale. Three distinct situations are found, where the presence of light extra…
Bounded masses in Two Higgs Doublets Models, Spontaneous CP Violation and symmetry
Miguel Nebot
In Two Higgs Doublet Models (2HDMs) shaped by some unbroken symmetry, imposing perturbativity requirements on the quartic couplings can imply that the allowed masses of all the fun…
Boundedness from below in the three-Higgs-Doublet model
Francisco S. Faro, Igor P. Ivanov
Establishing if multi-Higgs potentials are bounded from below (BFB) can be rather challenging, and it may impede efficient investigation of all phenomenological consequences of suc…
Hyperon electromagnetic timelike elastic form factors at large
G. Ramalho, M. T. Peña, K. Tsushima
We present estimates of the hyperon elastic form factors for the baryon octet and the baryon for large four-momentum transfer squared, , in the timelike region ()…
Higgs Quark Flavor Violation: Simplified Models and Status of General Two-Higgs-Doublet Model
Juan Herrero-Garcia, Miguel Nebot, Filip Rajec +2
We study quark flavor violating interactions mediated by the Higgs boson . We consider observables involving a third generation quark, of both the up and the down quark sectors,…
Symmetries and Mass Degeneracies in the Scalar Sector
Howard E. Haber, O. M. Ogreid, P. Osland +1
We explore some aspects of models with two and three SU(2) scalar doublets that lead to mass degeneracies among some of the physical scalars. In Higgs sectors with two scalar doubl…