1,212 research outputs found
A method to simulate inhomogeneously irradiated objects with a superposition of 1D models
In close binary systems the atmosphere of one or both components can be
significantly influenced by irradiation from the companion. Often the
irradiated atmosphere is simulated with a single-temperature approximation for
the entire half-sphere. We present a scheme to take the varying irradiation
angle into account by combining several separate 1D models. This is independent
of the actual code which provides the separate stellar spectra. We calculate
the projected area of zones with given irradiation angle and use this
geometrical factor to scale separate 1D models. As an example we calculate two
different irradiation scenarios with the PHOENIX code. The scheme to calculate
the projected area is applicable independent of the physical mechanism that
forms these zones. In the case of irradiation by a primary with T=125000 K, the
secondary forms ions at different ionisation states for different irradiation
angles. No single irradiation angle exists which provides an accurate
description of the spectrum. We show a similar simulation for weaker
irradiation, where the profile of the H line depends on the irradiation
angle.Comment: published in A&
IV.3 The wealth of stellar variability
This book is dedicated to all the people interested in the CoRoT mission and the beautiful data that were delivered during its six year duration. Either amateurs, professional, young or senior researchers, they will find treasures not only at the time of this publication but also in the future twenty or thirty years. It presents the data in their final version, explains how they have been obtained, how to handle them, describes the tools necessary to understand them, and where to find them. It also highlights the most striking first results obtained up to now. CoRoT has opened several unexpected directions of research and certainly new ones still to be discovered
Infestation by Aedes albopictus (skuse) in natural and artificial breeding sites found in green areas in the city of Fortaleza, Ceará
Repositório de acesso livre para agroecologia e agricultura orgânica do Brasil.
Resumo: Considerando que a literatura técnico-científica em Agroecologia e Agricultura Orgânica no Brasil é abundante, está dispersa e de difícil acesso, esse trabalho teve como objetivo criar e gerenciar um banco de dados da literatura no Brasil. Nesse sentido, há consenso na comunidade de especialistas e pesquisadores que estudam a informação, que a alternativa mais adequada e adotada em todo o mundo são os repositórios digitais de acesso aberto. Além de contemplarem os processos necessários para o gerenciamento da informação técnico-científica, os repositórios digitais de acesso aberto contribuem diretamente para a melhoria dos processos de comunicação na Ciência. Assim, o repositório escolhido para armazenar a literatura brasileira em Agroecologia e Agricultura Orgânica foi o Organic Eprints
Characterization of red wines aged with oak chip in the São Francisco Valley, Brazil.
This research aimed to characterize the physicochemical composition of Syrah tropical wines aged with oak chip addition
Traversable Casimir Wormholes in D Dimensions
In this paper, we study Casimir wormholes in arbitrary spacetime dimensions
D. Wormholes require negative energy, and therefore an exotic matter source.
Since Casimir energy is negative, it has been speculated as a good candidate to
source that objects a long time ago. However only very recently a full solution
has been found by Garattini [1]. The author found an appropriate redshift
function and proved that in four-dimensional spacetime, the Casimir energy can
be a source of traversable wormholes. Soon later Alencar et al have shown, in
[2], that this is not true in D = 3 and additional sources must be considered.
In this paper, we show that Casimir energy can be a source of the Morris-Thorne
wormhole for all spacetime dimensions with D > 3.Comment: 6 pages, 0 figure
Avaliação de sêmen congelado de bovinos. Provas lenta e rápida de termo-resistência: efeitos sobre a fertilidade.
O objetivo do presente trabalho foi avaliar a eficiência de sêmen congelado, submetido as provas rápida e lenta de termo-resistência, sobre a fertilidade de fêmeas da espécie bovina
- …