67 research outputs found
Limit on Higgs boson trilinear self-coupling in coupled technicolor models
No full textThe trilinear self-coupling of the Higgs boson, in a theory in which this boson is composite, is compared to the experimental bound of this quantity obtained by the CMS experiment. In the case of a model where technicolor (TC) is coupled to QCD, we find that the experimental result already constrains the dynamics of the theory, which is represented by an expression of the technifermion self-energy typical of technicolor coupled models, and function of the dynamically generated technifermion mass and two other parameters that describe the technifermion dynamical mass momentum dependence. The limits imposed on this dynamics allow us to make a simple determination of pseudo-Goldstone boson masses that appear in these theories, indicating that these bosons may be expected to be quite massive.Universidade Tecnológica Federal Do Parana UTFPR DAFIS, Av Monteiro Lobato Km 04, PRInstituto de Física Teórica UNESP, Rua Dr. Bento T. Ferraz, 271, SPInstituto de Física Teórica UNESP, Rua Dr. Bento T. Ferraz, 271, S
125 GeV scalar boson and SU(NTC)⊗ - SU(3) L⊗ - U(1)X models
No full textWe verify that SU(N)TC⊗ - SU(3) L⊗ - U(1)X models, where the gauge symmetry breaking is totally dynamical and promoted by the non-Abelian technicolor group and the strong Abelian interactions, are quite constrained by the LHC data. The theory contains a T quark self-energy involving the mixing between the neutral gauge bosons, which introduces the coupling between the light and heavy composite scalar bosons of the model. We determine the lightest scalar boson mass for these models from an effective action for composite operators, assuming details about the dynamics of the strong interaction theories. Comparing the value of this mass with the ATLAS and CMS observation of a new boson with a mass M∼125 GeV and considering the lower bound determined by the LHC Collaboration on the heavy neutral gauge boson (Z′) present in these models, we can establish constraints on the possible models. For example, if SU(N)TC≡SU(2)TC, with technifermions in the fundamental representation, the model barely survives the confrontation with the LHC data. © 2013 American Physical Society.Universidade Tecnológica Federal Do Paraná-UTFPR-DAFIS, Avenida Monteiro Lobato Km 04, 84016-210 Ponta Grossa, ParanáCentro de Ciências Naturais e Humanas Universidade Federal Do ABC, 09210-170 Santo-André, São PauloInstituto de Física Teórica UNESP, Rua Dr. Bento T. Ferraz, 271, Bloco II, 01140-070 São Paulo, SPInstituto de Física Teórica UNESP, Rua Dr. Bento T. Ferraz, 271, Bloco II, 01140-070 São Paulo, S
The 125 GeV boson: A composite scalar?
No full textAssuming that the 125 GeV particle observed at the LHC is a composite scalar and responsible for the electroweak gauge symmetry breaking, we consider the possibility that the bound state is generated by a non-Abelian gauge theory with dynamically generated gauge boson masses and a specific chiral symmetry breaking dynamics motivated by confinement. The scalar mass is computed with the use of the Bethe-Salpeter equation and its normalization condition as a function of the SU(N) group and the respective fermionic representation. If the fermions that form the composite state are in the fundamental representation of the SU(N) group, we can generate such a light boson only for one specific number of fermions for each group. We address the uncertainties underlying this result, when considering the strong dynamics in isolation. © 2013 American Physical Society.Universidade Tecnológica Federal Do Paraná (UTFPR) DAFIS, Avenida Monteiro Lobato Km 04, 84016-210 Ponta Grossa, ParanáInstituto de Física Universidade Federal Do Rio Grande Do sul, Caixa Postal 15051, 91501-970 Porto Alegre, Rio Grande do SulCentro de Ciências Naturais e Humanas Universidade Federal Do ABC, 09210-170 Santo André, São PauloInstituto de Física Teórica UNESP, Rua Dr. Bento T. Ferraz, 271, 01140-070 São PauloInstituto de Física Teórica UNESP, Rua Dr. Bento T. Ferraz, 271, 01140-070 São Paul
Towards a Brazilian radon map: consortium radon Brazil
No full textRecently, the idea of generating radon map of Brazil has emerged. First attempts of coordinating radon surveys-carried out by different groups across the country-and initial discussions on how to proceed on a larger scale were made at the First Brazilian Radon Seminary, Natal, September 2012. Conventionally, it is believed that indoor radon is no major problem in Brazil, because the overall benign climate usually allows high ventilation rates. Nevertheless, scattered measurements have shown that moderately high indoor radon concentrations (up to a few hundred Bq m(-)A(3)) do occur regionally. Brazilian geology is very diverse and there are regions where an elevated geogenic radon potential exists or is expected to exist. Therefore, a Brazilian Radon Survey is expected to be a challenge, although it appears an important issue, given the rising concern of the public about the quality of its environment.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG)CNEN, Lab Pocos Caldas LAPOC, BR-37701570 Caldas, P, BrazilGerman Fed Off Radioprotect BfS, D-10318 Berlin, GermanyCNEN, Northeast Reg Ctr Nucl Sci CRCN NE, Recife, PE, BrazilUniv Fed Rio Grande do Norte, Lab Nat Radioact, BR-59078970 Natal, RN, BrazilUniv Coimbra, Dept Earth Sci IMAR CMA, P-3000272 Coimbra, PortugalUniv Sao Paulo IFUSP, Inst Phys, BR-05314970 Sao Paulo, BrazilCNEN, IRD, Rio De Janeiro, BrazilCNEN, Ctr Dev Nucl Technol CDTN, BR-31270901 Belo Horizonte, MG, BrazilCNEN, Lab Nat Radioact, Nucl & Energy Res Inst IPEN, BR-0558000 Sao Paulo, BrazilFed Technol Univ Parana DAFIS, UFTPR, Dept Phys, BR-80230901 Curitiba, Parana, BrazilState Univ Sao Paulo IGCE UNESP, Dept Petr & Metallogeny, Rio Claro, SP, BrazilState Univ Sao Paulo IGCE UNESP, Dept Petr & Metallogeny, Rio Claro, SP, Brazi
Database on detected stellar occultations by small outer Solar System objects
No full textObservation of stellar occultation by objects of the Solar System is a powerful technique that allows measurements of size and shape of the small bodies with accuracies in the order of the kilometre. In addition, the occultation star probes the surroundings of the object, allowing the study of putative rings/debris or atmosphere around it. Since 2009, more than 60 events by trans-Neptunian and Centaur objects have been detected, involving more than 34 different bodies. Some remarkable results were achieved, such as the discovery of rings around Chariklo and Haumea, or the high albedo of Eris, the lack of global atmosphere around Makemake and the discovery of the double shape of 2014 MU69, among others. After the release of Gaia catalogues, predictions became more accurate, leading to an increasing number of successful observations of occultation events. To keep track of the results achieved with this technique, we created a database to gather all the detected events worldwide. The database is presented as an electronic table (http://occultations.ct.utfpr.edu.br/), where the main information obtained from any occultation by small outer solar system objects are listed. The structure and term definitions used in the database are presented here, as well as some simple statistics that can be done with the available results.Federal University of Technology Paraná (UTFPR-DAFIS)LESIA Observatoire de Paris PSL Research University CNRS Sorbonne Université UPMC Univ. Paris 06 Univ. Paris Diderot Sorbonne Paris CitObservatório Nacional (ON/MCTIC)Laboratório Interinstitucional de E-Astronomia (LIneA) INCT Do E-UniversoInstituto de Astrofísica de Andalucía IAA-CSIC, Glorieta de la Astronomía s/nObservatório Do Valongo UFRJUNESP São Paulo State University Grupo de Dinâmica Orbital e PlanetologiaUNESP São Paulo State University Grupo de Dinâmica Orbital e Planetologi
Guidelines for the rehabilitation of degraded oak forests
No full textThe present edition focuses on the rehabilitation of the coppice oak forests through selective inversion thinnings that have already been applied with positive results on both the biodiversity and the productivity of the forests
Observational and Numerical Study of a Tornado Outbreak in Attica and Euboea
No full textOn October 22, 2015, a rare tornado outbreak occurred in Attica and southern parts of Euboea island, in central Greece. Seven tornado events were recorded by several storm-cells, accompanied with 3.5 cm hail and large amounts of precipitation up to 180 mm, resulting in flash flood causing severe structural damage and 3 human casualties. In this study we investigate the synoptic and mesoscale weather conditions triggering and sustaining ingredients for deep convection and physical mechanisms leading to this extreme tornadogenesis by using upper-air measurements, satellite and Doppler radar data. Furthermore, an interesting interaction between gravity waves and tornadogenesis is also studied through numerical simulations of the Weather Research Forecast model (WRF) in fine resolution. The model was able to fairly reproduce the mesoscale environment associated with the formation of these supercells, showing the presence of 1500 J/kg MLCAPE which overlapped with 20 m/s of 0-6 km Bulk Shear. Furthermore a southwesterly low level flow forced unstable air masses from Saronicos gulf
Ianos—A Hurricane in the Mediterranean
No full textInternational audienceDuring 15-21 September 2020, an intense medicane, named Ianos, formed over the warm Mediterranean Sea. Following a path of approximately 1,900 km, Medicane Ianos affected Greece resulting in four casualties and devastating damage in the western and central parts of Greece. Persistent gale force 1-min winds up to 44 m s−1 and wind gusts up to 54 m s−1 were recorded in Cephalonia Island (Ionian Sea), while record-breaking amounts of accumulated rainfall have been recorded in several Ionian islands, as well as in parts of central Greece. Analysis of the available observations showed that Ianos was the most intense medicane ever recorded in the Mediterranean. This paper aims at investigating the genesis and evolution of the medicane, based on in situ observations, satellite measurements, and model analyses. Toward that objective, Meteosat Second Generation (MSG) SEVIRI imagery, combined with lightning data permitted to follow the evolution of convective activity during the various phases of Ianos. This investigation is complemented with upper-air model analyses in order to evaluate the synoptic environment within which Ianos had formed and was sustained over 7 days. Finally, the Global Precipitation Measurement Core Observatory (GPM CO) satellite overpasses over Medicane Ianos provided invaluable information about its 3D structure, especially during its most intense phase
Global monitoring of deep convection using passive microwave observations
No full textInternational audienceIn this study, we present the DEEPSTORM (DEEP moiSt aTmospheric cOnvection from micRowave radioMeter) algorithm, able to retrieve ice water path (IWP) and to detect deep moist atmospheric convection (DC) from 80°S to 80°N using observations from four spaceborne passive microwave radiometers. DEEPSTORM is based on a machine learning approach and is fitted against observations from the CPR (Cloud Profiling Radar) spaceborne radar on-board CloudSat. IWP predictions show an average root mean square error of 0.27 kg/m2 and a correlation index of 0.87. DC occurrence is detected with a probability of 59% and a false alarm rate of 24%. The prediction accuracy of IWP and DC is significantly better when the IWP exceeds 0.5 kg/m2 showing that DEEPSTORM is well suited to detect and characterise the strongest DC events. Overall DC detection is more accurate in the tropics than in mid-latitudes while the IWP retrieval works better in the mid-latitudes. Two examples illustrating the potential of DEEPSTORM are presented: the IWP is retrieved during Hurricane Matthew in 2016, and a climatology of DC occurrences between September 2016 and December 2016 is presented. This work will allow building a quasi-worldwide and 20-year long database of DC occurrence and intensity
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