5,215 research outputs found
Probing doubly charged Higgs in Colliders in 3-3-1 Model
The SU(3)_L\otimesU(1)_N electroweak model predicts new Higgs bosons beyond
the one of the standard model. In this work we investigate the signature and
production of doubly charged Higgs bosons in the International Linear
Collider and in the CERN Linear Collider. We compute the branching ratios for
the doubly charged gauge bosons of the model.Comment: 17 pages, 12 figure
Concentrations of Hg, Pb, Zn, Cd, and As in Timbalier Bay and the Louisiana Oil Patch
Paper by J. G. Montalvo, Jr., and D. V. Brad
Doubly charged Higgs from - scattering in the 3-3-1 Model
We studied the production and signatures of doubly charged Higgs bosons in
the process , where is a heavy lepton,
at the International Linear Collider (ILC) and CERN Linear Collider
(CLIC). The intermediate photons are given by the Weizscker-Williams
and laser backscattering distributions. We found that significant signatures
are obtained by bremsstrahlung and backward Comptom scattering of laser. A
clear signal can be obtained for doubly charged Higgs bosons, doubly charged
gauge bosons and heavy leptons
Searching for doubly charged Higgs bosons at the LHC in a 3-3-1 Model
Using a peculiar version of the SU(3)L x U(1)N electroweak model, we
investigate the production of doubly charged Higgs boson at the Large Hadron
Collider. Our results include branching ratio calculations for the doubly
charged Higgs and for one of the neutral scalar bosons of the model.Comment: 19 pages, 3 figure
t-channel production of heavy charged leptons
We study the pair production of heavy charged exotic leptons at e+ e-
colliders in the SU(2)_L x SU(2)_I x U(1)_Y model. This gauge group is a
subgroup of the grand unification group E6; SU(2)_I commutes with the electric
charge operator, and the three corresponding gauge bosons are electrically
neutral. In addition to the standard photon and Z boson contributions, we also
include the contributions from extra neutral gauge bosons. A t-channel
contribution due to W_I-boson exchange, which is unsuppressed by mixing angles,
is quite important. We calculate the left-right and forward-backward
asymmetries, and discuss how to differentiate different models.Comment: Increased discussion of experimental signatures. Version accepted by
PR
Estima de la abundancia de palomas (Columba livia var.) de la ciudad de Barcelona y valoración de la efectividad del control por eliminación de individuos
Uno de los métodos más comúnmente utilizados para el control de las poblaciones de palomas urbanas es la captura y eliminación selectiva de individuos. Con este método, la Agencia de Salud Pública de Barcelona (ASPB) eliminó entre 1991 y 2006, un total de 227.479 palomas. En el presente trabajo se compara la abundancia de palomas de la ciudad de Barcelona estimada en 1991 (183.887±14.914), con los valores obtenidos en una nueva estima realizada en 2006, con un total de 256.663±26.210 (IC 95%) palomas. Mientras que en el centro de la ciudad la densidad de palomas no aumentó entre esos años, la densidad en todo el anillo que rodea el centro aumentó de forma significativa, conduciendo a un aumento global de toda la población urbana. El número de denuncias recibidas por distrito por molestias ocasionadas por las palomas no se correlacionó con su abundancia. El esfuerzo de capturas por distrito realizado por la ASPB se correlacionó con la abundancia de palomas y no con el número de denuncias recibidas, lo que indica que las actuaciones realizadas siguen en general un protocolo técnico. La densidad de palomas por distrito se correlacionó significativamente con la densidad de habitantes de cada distrito, pero no con el número total de habitantes. Los datos presentados demuestran la baja efectividad de las medidas de control de palomas por eliminación de individuos, y abogan por un mayor énfasis en los métodos de control centrados en los factores limitantes de la especie, en concreto la oferta alimentaria y los lugares de nidificación.
Palabras clave: Abundancia, Eliminación de individuos, Poblaciones de paloma, Columba livia var., Factores limitantes.Culling is one of the most commonly used methods to control urban pigeon populations. The Barcelona Public Health Agency (ASPB) eliminated a total of 227,479 pigeons using this technique between 1991 and 2006. We compared the estimate of abundance of pigeons in Barcelona city in 1991 (183.667±14.914) with that in 2006 (256.663±26.210) (CI 95%). While pigeon density did not increase in the city centre during this period, density in a ring around the city increased significantly, leading to a general increase in the urban population of these birds. The number of complaints regarding pigeons received per district did not correlate with abundance. ASPB culling per district correlated with abundance and not with numbers of complaints received, indicating interventions generally followed a technical protocol. Pigeon density per district correlated significantly with the human population density but not with the total number of inhabitants. Findings indicate the effectiveness of culling is low in this setting and suggest greater emphasis should be placed on control measures centered on limiting factors, particularly reduction of food availability and nest removal.
Key words: Abundance, Culling, Feral Pigeon populations, Columba livia var., Limiting factorsUno de los métodos más comúnmente utilizados para el control de las poblaciones de palomas urbanas es la captura y eliminación selectiva de individuos. Con este método, la Agencia de Salud Pública de Barcelona (ASPB) eliminó entre 1991 y 2006, un total de 227.479 palomas. En el presente trabajo se compara la abundancia de palomas de la ciudad de Barcelona estimada en 1991 (183.887±14.914), con los valores obtenidos en una nueva estima realizada en 2006, con un total de 256.663±26.210 (IC 95%) palomas. Mientras que en el centro de la ciudad la densidad de palomas no aumentó entre esos años, la densidad en todo el anillo que rodea el centro aumentó de forma significativa, conduciendo a un aumento global de toda la población urbana. El número de denuncias recibidas por distrito por molestias ocasionadas por las palomas no se correlacionó con su abundancia. El esfuerzo de capturas por distrito realizado por la ASPB se correlacionó con la abundancia de palomas y no con el número de denuncias recibidas, lo que indica que las actuaciones realizadas siguen en general un protocolo técnico. La densidad de palomas por distrito se correlacionó significativamente con la densidad de habitantes de cada distrito, pero no con el número total de habitantes. Los datos presentados demuestran la baja efectividad de las medidas de control de palomas por eliminación de individuos, y abogan por un mayor énfasis en los métodos de control centrados en los factores limitantes de la especie, en concreto la oferta alimentaria y los lugares de nidificación.
Palabras clave: Abundancia, Eliminación de individuos, Poblaciones de paloma, Columba livia var., Factores limitantes
Signatures of Double Charged Higgs in model
The scalar sector of the simplest version of the 3-3-1 electroweak models is
constructed with three Higgs triplets only. We show that a relation involving
two of the constants of the Higgs potential, two vacuum expectation values of
the neutral scalars and the mass of the doubly charged Higgs boson leads to
important information concerning the signals of this scalar particle.Comment: 6 pages and 9 figure
Possibilities for charged Higgs bosons at the LHC in a SU(3)_L\otimesU(1)_N Model
We have studied the branching ratios of doubly charged Higgs bosons at the
LHC using a version of the SU(3)_L\otimesU(1)_N electroweak model. At the end
of this work we have made a very simple plotting comparating the total cross
section of this model using Drell-Yan, gluon-gluon fusion and Left-right
symmetric model.Comment: Talk given at 18th International IUPAP Conference on Few-Body
Problems in Physics (FB18), Santos, Sao Paulo, Brazil, 21-26 Aug 200
Ultraviolet resonance Raman spectroscopy for the detection of cocaine in oral fluid
Detecting and quantifying cocaine in oral fluid is of significant importance for practical forensics. Up to date, mainly destructive methods or biochemical tests have been used, while spectroscopic methods were only applied to pretreated samples. In this work, the possibility of using resonance Raman spectroscopy to detect cocaine in oral fluid without pretreating samples was tested. It was found that ultraviolet resonance Raman spectroscopy with 239-nm excitation allows for the detection of cocaine in oral fluid at 10 mu g/mL level. Further method development will be needed for reaching the practically useful levels of cocaine detection. (C) 2017 Elsevier B.V. All rights reserved
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