20,796 research outputs found
Topological vortices in generalized Born-Infeld-Higgs electrodynamics
A consistent BPS formalism to study the existence of topological axially
symmetric vortices in generalized versions of the Born-Infeld-Higgs
electrodynamics is implemented. Such a generalization modifies the field
dynamics via introduction of three non-negative functions depending only in the
Higgs field, namely, , and . A set of
first-order differential equations is attained when these functions satisfy a
constraint related to the Ampere law. Such a constraint allows to minimize the
system energy in such way that it becomes proportional to the magnetic flux.
Our results provides an enhancement of topological vortex solutions in
Born-Infeld-Higgs electrodynamics. Finally, we analyze a set of models such
that a generalized version of Maxwell-Higgs electrodynamics is recovered in a
certain limit of the theory.Comment: 8 pages, 8 figures, to appear in EPJ
Analytical BPS Maxwell-Higgs vortices
We have established a prescription for the calculation of analytical vortex
solutions in the context of generalized Maxwell-Higgs models whose overall
dynamics is controlled by two positive functions of the scalar field. We have
also determined a natural constraint between these functions and the Higgs
potential allowing the existence of axially symmetric
Bogomol'nyi-Prasad-Sommerfield (BPS) solutions possessing finite energy.
Furthermore, when the generalizing functions are chosen suitably, the
nonstandard BPS equations can be solved exactly. We have studied some examples,
comparing them with the usual Abrikosov-Nielsen-Olesen (ANO) solution. The
overall conclusion is that the analytical self-dual vortices are well-behaved
in all relevant sectors, strongly supporting the generalized models they belong
themselves. In particular, our results mimic well-known properties of the usual
(numerical) configurations, as localized energy density, while contributing to
the understanding of topological solitons and their description by means of
analytical methods.Comment: 8 pages, 4 figure
Avaliação socioeconômica de sistemas produtivos de banana na região ribeirinha do Juruá, Acre.
Introdução; Metodologia; Abragência dos sistemas de produção; Identificação e caracterização dos sistemas de produção; Avaliação sócioeconômica; Orçamentos; Mão de obra familiar; despesas com ferramenta, equipamentos e instalações; Preços de materiais e serviços para os orçamentos; Indicadores socioeconômicos; Resultados; Abreviações utilizadas; Sistema de produção tradicional de banana na região do Vale do Rio Juruá, Acre; Sistema de produção melhorado de banana na região do Vale do Rio Juruá, Acre; Análise comparativa entre os sistemas de produção tradicional e melhorado; Consideraçãoes finaisbitstream/item/144205/1/7309.pd
Elodie metallicity-biased search for transiting Hot Jupiters I. Two Hot Jupiters orbiting the slightly evolved stars HD118203 and HD149143
We report the discovery of a new planet candidate orbiting the subgiant star
HD118203 with a period of P=6.1335 days. The best Keplerian solution yields an
eccentricity e=0.31 and a minimum mass m2sin(i)=2.1MJup for the planet. This
star has been observed with the ELODIE fiber-fed spectrograph as one of the
targets in our planet-search programme biased toward high-metallicity stars,
on-going since March 2004 at the Haute-Provence Observatory. An analysis of the
spectroscopic line profiles using line bisectors revealed no correlation
between the radial velocities and the line-bisector orientations, indicating
that the periodic radial-velocity signal is best explained by the presence of a
planet-mass companion. A linear trend is observed in the residuals around the
orbital solution that could be explained by the presence of a second companion
in a longer-period orbit. We also present here our orbital solution for another
slightly evolved star in our metal-rich sample, HD149143, recently proposed to
host a 4-d period Hot Jupiter by the N2K consortium. Our solution yields a
period P=4.09 days, a marginally significant eccentricity e=0.08 and a
planetary minimum mass of 1.36MJup. We checked that the shape of the spectral
lines does not vary for this star as well.Comment: Accepted in A&A (6 pages, 6 figures
Antecipação da adubação nitrogenada de cobertura do arroz de terras altas em sistema plantio direto.
Um experimento de campo está sendo conduzido na Fazenda Capivara da Embrapa Arroz e Feijão com o objetivo de avaliar o efeito da antecipação da adubação nitrogenada de cobertura no desenvolvimento e produtividade de arroz de terras altas (Primavera CL) cultivado em SPD, utilizando diferentes fontes de N
Proving two partition identities
In this paper we give combinatorial proofs for two partition identities. The first one solves a recent open question formulated by G. E. Andrews.Neste artigo fornecemos provas combinatórias para duas identidades de partições. A primeira resolve uma questão recentemente formulada por G. E. Andrews.13314
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