New and recent results from the ATLAS programme of studies in EW physics with open beauty are presented. Particular attention will be given to measurements involving FCNC processes in Bs and Bd mesons decays ( that are sensitive to New Physics contributions through corrections to the EW loop amplitudes) and to studies of CP violation in the Bs sector.
The most recent results from ATLAS are...
The Nambu--Jona-Lasinio model is the classic model of nonperturbative physics generating an effective Higgs field as dynamical composite giving symmetry breaking and mass generation. We discuss the line of supersymmetric versions of NJL type models we studied in the recent years and their possible phenomenological applications in the setting of the supersymmetric standard model. The nontrivial...
We study a scenario inspired by natural supersymmetry, where neutrino data is explained within a low-scale seesaw scenario. We extend the MSSM by adding light right-handed neutrinos and their superpartners, the R-sneutrinos, and consider the lightest neutralinos to be higgsino-like.
We consider the possibility of having an R-sneutrino as lightest supersymmetric particle. Assuming that some...
Despite the absence of experimental evidence, weak-scale supersymmetry remains one of the best motivated and studied Standard Model extensions. This talk summarises recent ATLAS results on searches for SUSY, including strong production and electroweak production. Strong limits can be set on gluino and squark (including stop) production with recent data. Several searches explore long-lived...
The dipole approach provides all the necessary means for a universal treatment of both inclusive and diffractive reactions. In this presentation, I will classify various sources of diffractive factorisation breakingin hadronic collisions in both diffractive Abelian and non-Abelian radiation as apparent in the dipole picture, as well as give a short overview of the recent advances in treatment...
In this work we test a multivariate method to differentiate between particle showers produced by cosmic rays and by gamma rays at TeV energies, using CORSIKA simulations. The aim is to solve the dominant hadron flux background problem when looking for gamma-ray signals measured by different experiments. The results of this work can be applied to the study of Gamma-Ray Bursts (GRBs). GRBs emit...
The aim of the present work is to correlate highly energetic, short lived events in the radio
wave spectrum, known as Fast Radio Bursts (FRB), and compact radio sources known as
Faranoff-Riley 0 (FR-0) with gamma rays using data from the Fermi satellite.
FRB's origin is still unknown, although, given their spatial distribution, an extragalactic origin is
suspected. Up to date, only one FRB...
The Latin American Giant Observatory (LAGO) consists of a network of water Cherenkov detectors (WCDs) with the aim of measuring the secondary cosmic rays flux at ground level. It is distributed across 10 countries in Latin America, from Mexico to Antarctica, at several altitudes, from sea level to 5200 m.a.s.l. The decentralized nature of this network has forced the development of a simple and...
We built desktop particle detectors based on a design from MIT. We use them for measuring two characteristics of atmospheric muons: their angular distribution at sea level and their attenuation for lead and concrete layers. We also made a comparison between the actual measurements and the expected results from simulations based on Geant4. Finally, we explored the application of the detectors...
The influence of the extra dimension on the static equilibrium configurations and the stability against radial perturbations are analyzed. These studies are investigated by using the stellar structure equations and the radial perturbation equations, both modified for a $d$-dimensional spacetime. We obtain that the spacetime dimension influences in both structure and stability of an object,...
After the discovery of the Higgs boson in summer 2012, the understanding its properties has been a high priority of the ATLAS physics program. Measurements of Higgs boson properties sensitive to its production processes, decay modes, kinematics, mass, and spin/CP properties based on pp collision data recorded at 13 TeV are presented. The analyses in several decay channels will be described and...
In this work we study the effects of new physics in double Higgs production at future $e^+ e^-$ colliders. In particular, we consider the possibility of an enhancement due to the contribution of SM dimension-six effective operators. We perform this study for several benchmarks of energy and integrated luminosity related to several proposed linear colliders such as CLIC, ILC and FCC-ee. We...
Several theories beyond the Standard Model predict the existence of additional neutral or charged Higgs particles, as well as decays of the Higgs boson that are either forbidden or strongly suppressed in the SM.
Results from selected recent searches for additional Higgs bosons in different production processes and decay modes, and for BSM decays of the 125 GeV-Higgs boson will be presented.
In this work, we categorize and discuss the maximum contributions to the muon magnetic moment $a_{\mu}$ as well as to the Yukawa and triple Higgs couplings in the flavour-aligned two-Higgs doublet model (2HDM). We focus on the most promising case of a light pseudoscalar Higgs A with large Yukawa couplings to leptons and quarks. By taking into account experimental constraints from LHC, Higgs...
The chromomagnetic dipole moment (CMDM) and chromoelectric dipole moment (CEDM) of the top quark are calculated at the one-loop level in the framework of the two-Higgs doublet model with four fermion generations (4GTHDM), which is still consistent with experimental data and apart from new scalar bosons ($H^0$, $A^0$, and $H^\pm$) and quarks ($b'$ and $t'$) predicts new sources of $CP$...
Standard-model elds and their associated electroweak Lagrangian are equivalently expressed in a shared spin basis. The scalar-vector terms are written with scalar-operator components acting on quark-doublet elements, and shown to be parametrization-invariant. Such terms, and the t- and b-quark Yukawa terms are linked by the identification of the common mass-generating Higgs operating upon the...
Reliable estimates of the allowed range for axion couplings to photons, nucleons and electrons are of major importance for determining the viable axion mass window as well as to focus experimental axion searches.
We show that in a class of generalized DFSZ axion models with generation dependent Peccei-Quinn charges the axion couplings to nucleons and electrons can be simultaneously...
We seek to study how the observed spectrum of cosmological photons is modified if a theory that considers new particles is incorporated,
analogues to the usual photons, called Hidden Photons and axion-like particles.
To study these possible modifications, we introduce a model that contains parameters that correspond to the masses and couplings for both new particles. These being free...
The dark matter problem is one of the major subjects of physics these days. The search for hints in the high and low mass range are intense. A quite popular candidate is the axion, a very light hypothetical particle that can only account for the whole dark matter in a window of mass around the $\mu$eV. Recently has been found that one way to open up this window is if the axion is coupled to a...
The presence of a non-baryonic dark matter component in the Universe is inferred from the observation of its gravitational interaction. If dark matter interacts weakly with the Standard Model it would be produced at the LHC, escaping the detector and leaving a large missing transverse momentum as their signature. The ATLAS detector has developed a broad and systematic search program for dark...
Searches in CMS for dark matter in final states with invisible particles recoiling against visible states are presented. Various topologies and kinematic variables are explored, including jet substructure as a mean of tagging heavy bosons. The focus of the talk is the recent results obtained using data collected at Run-II of the LHC.
The fundamental description of nature, beyond the Standard Model (SM), may include heavy neutrinos that mix and thus allow processes in which lepton flavor is not preserved. We investigate the impact of charged currents that couple heavy gauge bosons to heavy neutrinos and SM leptons on neutrinoless lepton-flavor-violating decays of SM leptons into three charged leptons. We implement our...
One of the open questions in particle physics is to know the nature of neutrinos, that is, to know if they are Dirac or Majorana particles. One of the most accepted models for the generation of neutrino mass is the Seesaw model, if we also consider an approximate lepton number symmetry, these can be tested in colliders. Here we consider an extension of the standard model, where we add two...
We study the capability of angular and polarization observables to disentangle different new physics contributions to the production of heavy sterile Majorana neutrinos in the lepton number violating channels $e^{-}p\rightarrow l_{j}^{+} + 3 jets$ ($l_j\equiv e ,\mu $) and $e^{+}e^{-}\rightarrow \tau^{+} \tau^{+}+ 4 jets$ in electron-proton and electron-positron colliders. This is done...
We study the feasibility of observing deviations from the CPT symmetry owing to quantum decoherence and in the framework of the neutrino oscillations. Taking into account the open system approach, and considering non-diagonal decoherence matrizes, we study all the cases in which CPT violation (CPTV) terms that could be arising in the neutrino oscillation probabilities. Moreover, and based on...
In this talk I will discuss the impact of recent COHERENT data on neutrino generalized interactions. I will show that scalar nuclear currents are the most constrained, while vector and tensor still allow for sizable effective couplings. I will discuss as well some implications of vector generalized interactions and will comment on the impact they have in the data fit.
The consequences of introducing matter effects into the neutrino visible decay scheme are studied. To this end, we select two
baselines for which matter effects have to be considered:1300 km (DUNE) and 7650 km(considering an hypothetical
beam aimed towards ANDES). The matter effects are almost unnoticeable for the visible decay contribution DUNE, being sizable at ANDES. We also carry out a...
Magnetic fields are present in compact objects affecting its structure. The anisotropy produced by the magnetic field in the pressures suggests the necessity of using structure equations considering the axial symmetry of the magnetized system. In this work, we propose a model that generalizes the Tolman-Oppenheimer-Volkoff equations for the magnetized case and discuss some preliminary results....