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Generalized Ginzburg-Landau approach to inhomogeneous phases in nonlocal chiral quark models

Carlomagno, J. P.; Dumm, D. Gomez; Scoccola, N. N.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
16.54%
We analyze the presence of inhomogeneous phases in the QCD phase diagram within the framework of nonlocal chiral quark models. We concentrate in particular in the positions of the tricritical (TCP) and Lifshitz (LP) points, which are studied in a general context using a generalized Ginzburg-Landau approach. We find that for all the phenomenologically acceptable model parametrizations considered the TCP is located at a higher temperature and a lower chemical potential in comparison with the LP. Consequently, these models seem to favor a scenario in which the onset of the first order transition between homogeneous phases is not covered by an inhomogeneous, energetically favored phase.; Comment: 9 pages, 1 figure. V2: Two references added, figure modified, minor changes in the text introduced. Matches version to be published in Physics Letters B

The VORTEX project: first results and perspectives

Absil, Olivier; Mawet, Dimitri; Delacroix, Christian; Forsberg, Pontus; Karlsson, Mikael; Habraken, Serge; Surdej, Jean; Absil, Pierre-Antoine; Carlomagno, Brunella; Christiaens, Valentin; Defrere, Denis; Gonzalez, Carlos Gomez; Huby, Elsa; Jolivet, Aissa
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 21/10/2014
Relevância na Pesquisa
16.54%
(abridged) Vortex coronagraphs are among the most promising solutions to perform high contrast imaging at small angular separations. They feature a very small inner working angle, a clear 360 degree discovery space, have demonstrated very high contrast capabilities, are easy to implement on high-contrast imaging instruments, and have already been extensively tested on the sky. Since 2005, we have been designing, developing and testing an implementation of the charge-2 vector vortex phase mask based on concentric subwavelength gratings, referred to as the Annular Groove Phase Mask (AGPM). Science-grade mid-infrared AGPMs were produced in 2012 for the first time, using plasma etching on synthetic diamond substrates. They have been validated on a coronagraphic test bench, showing broadband peak rejection up to 500:1 in the L band, which translates into a raw contrast of about $6\times 10^{-5}$ at $2 \lambda/D$. Three of them have now been installed on world-leading diffraction-limited infrared cameras (VLT/NACO, VLT/VISIR and LBT/LMIRCam). During the science verification observations with our L-band AGPM on NACO, we observed the beta Pictoris system and obtained unprecedented sensitivity limits to planetary companions down to the diffraction limit ($0.1''$). More recently...

Development of a subwavelength grating vortex coronagraph of topological charge 4 (SGVC4)

Delacroix, Christian; Absil, Olivier; Carlomagno, Brunella; Piron, Pierre; Forsberg, Pontus; Karlsson, Mikael; Mawet, Dimitri; Habraken, Serge; Surdej, Jean
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 01/12/2014
Relevância na Pesquisa
16.54%
One possible solution to achieve high contrast direct imaging at a small inner working angle (IWA) is to use a vector vortex coronagraph (VVC), which provides a continuous helical phase ramp in the focal plane of the telescope with a phase singularity in its center. Such an optical vortex is characterized by its topological charge, i.e., the number of times the phase accumulates 2{\pi} radians along a closed path surrounding the singularity. Over the past few years, we have been developing a charge-2 VVC induced by rotationally symmetric subwavelength gratings (SGVC2), also known as the Annular Groove Phase Mask (AGPM). Since 2013, several SGVC2s (or AGPMs) were manufactured using synthetic diamond substrate, then validated on dedicated optical benches, and installed on 10-m class telescopes. Increasing the topological charge seems however mandatory for cancelling the light of bright stars which will be partially resolved by future Extremely Large Telescopes in the near-infrared. In this paper, we first detail our motivations for developing an SGVC4 (charge 4) dedicated to the near-infrared domain. The challenge lies in the design of the pattern which is unrealistic in the theoretically perfect case, due to state-of-the-art manufacturing limitations. Hence...

Lyot-plane phase masks for improved high-contrast imaging with a vortex coronagraph

Ruane, Garreth J.; Huby, Elsa; Absil, Olivier; Mawet, Dimitri; Delacroix, Christian; Carlomagno, Brunella; Swartzlander, Grover A.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 18/09/2015
Relevância na Pesquisa
16.54%
The vortex coronagraph is an optical instrument that precisely removes on-axis starlight allowing for high contrast imaging at small angular separation from the star, thereby providing a crucial capability for direct detection and characterization of exoplanets and circumstellar disks. Telescopes with aperture obstructions, such as secondary mirrors and spider support structures, require advanced coronagraph designs to provide adequate starlight suppression. We introduce a phase-only Lyot-plane optic to the vortex coronagraph that offers improved contrast performance on telescopes with complicated apertures. Potential solutions for the European Extremely Large Telescope (E-ELT) are described and compared. Adding a Lyot-plane phase mask relocates residual starlight away from a region of the image plane thereby reducing stellar noise and improving sensitivity to off-axis companions. The phase mask is calculated using an iterative phase retrieval algorithm. Numerically, we achieve a contrast on the order of $10^{-6}$ for a companion with angular displacement as small as $4~\lambda/D$ with an E-ELT type aperture. Even in the presence of aberrations, improved performance is expected compared to either a conventional vortex coronagraph or optimized pupil plane phase element alone.; Comment: 6 pages...

Optimized focal and pupil plane masks for vortex coronagraphs on telescopes with obstructed apertures

Ruane, Garreth J.; Absil, Olivier; Huby, Elsa; Mawet, Dimitri; Delacroix, Christian; Carlomagno, Brunella; Piron, Pierre; Swartzlander Jr, Grover A.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 18/09/2015
Relevância na Pesquisa
16.54%
We present methods for optimizing pupil and focal plane optical elements that improve the performance of vortex coronagraphs on telescopes with obstructed or segmented apertures. Phase-only and complex masks are designed for the entrance pupil, focal plane, and the plane of the Lyot stop. Optimal masks are obtained using both analytical and numerical methods. The latter makes use of an iterative error reduction algorithm to calculate "correcting" optics that mitigate unwanted diffraction from aperture obstructions. We analyze the achieved performance in terms of starlight suppression, contrast, off-axis image quality, and chromatic dependence. Manufacturing considerations and sensitivity to aberrations are also discussed. This work provides a path to joint optimization of multiple coronagraph planes to maximize sensitivity to exoplanets and other faint companions.

Deconfinement and chiral restoration in nonlocal SU(3) chiral quark models

Carlomagno, J. P.; Dumm, D. Gomez; Scoccola, N. N.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
16.54%
We study the features of nonlocal SU(3) chiral quark models with wave function renormalization. Model parameters are determined from meson phenomenology, considering different nonlocal form factor shapes. In this context we analyze the characteristics of the deconfinement and chiral restoration transitions at finite temperature, introducing the couplings of fermions to the Polyakov loop. We analyze the results obtained for various thermodynamical quantities considering different Polyakov loop potentials and nonlocal form factors, in comparison with data obtained from lattice QCD calculations.; Comment: 25 pages, 5 figures. Discussion of results enlarged, figures modified, references added. Version to appear in Physical Review D

La pervivencia y utilización histórica del mito: los casos de Carlomagno y Federico I Barbarroja

Diago Hernando, Máximo
Fonte: Consejo Superior de Investigaciones Científicas (España) Publicador: Consejo Superior de Investigaciones Científicas (España)
Tipo: Artículo Formato: 181207 bytes; application/pdf
SPA
Relevância na Pesquisa
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Ponencia presentada en la XIII Semana de Estudios Medievales, Nájera, del 29 de julio al 2 de agosto de 2002; La época medieval fue un tiempo en que en la Europa occidental proliferaron de forma extraordinaria los mitos, pues no en vano entonces lo maravilloso y todo lo que escapaba a la comprensión racional de la realidad ocupaba un lugar en la mentalidad colectiva mucho más importante que el que ha tenido reservado en momentos posteriores de la historia del continente, muy en especial a parti~d el siglo m, conforme se fueron imponiendo los principios del racionalismo. Estos mitos se crearon en muchos casos a partir de personajes reales de la historia, que fueron rodeados a posteriori de innumerables elementos legendarios que propiciaron que finalmente su imagen terminase quedando totalmente desfigurada en la mentalidad colectiva, al atribuirseles cualidades que no habían poseído en su existencia real. Un mismo personaje histórico con frecuencia dio origen de hecho a múltiples leyendas de muy variado signo, en cada una de las cuales adoptaba un perfil muy diferente, llegando a consolidarse de esta manera como un auténtico mito polifacético.; Peer reviewed

Épica e imperio imitación virgiliana y propaganda política en la épica española /

Vilà i Tomàs, Lara
Fonte: Bellaterra : Universitat Autònoma de Barcelona, Publicador: Bellaterra : Universitat Autònoma de Barcelona,
Tipo: Tesis i dissertacions electròniques; info:eu-repo/semantics/doctoralThesis Formato: application/pdf; application/pdf; application/pdf; application/pdf; application/pdf; application/pdf
Publicado em //2003 SPA; SPA
Relevância na Pesquisa
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Consultable des del TDX; Títol obtingut de la portada digitalitzada; Este trabajo propone un estudio de la épica española del siglo XVI desde una perspectiva política, y quiere demostrar que una de las finalidades principales del género es ofrecer una visión mítica y simbólica del poder -en este caso, del emperador Carlos V y su descendiente Felipe II- y cómo esta característica fundamental determina en gran medida la naturaleza del género y la manera cómo debe ser analizado. Lo que se pretende demostrar es de qué forma la épica, al igual que otros productos textuales contemporáneos de distinta naturaleza (particularmente, la historiografía o la iconografía) no puede considerarse un reflejo de la realidad sino, todo lo contrario, un medio para la construcción de la realidad. Por ello, este trabajo aborda una lectura de los textos españoles a partir de la consideración, por una parte, de la tradición literaria, especialmente de la Eneida de Virgilio, que sería considerado el modelo por excelencia de la épica y sobre cuyo ejemplo se configuraría la tradición épica a lo largo de los siglos posteriores. Por otra parte, se atiende a las circunstancias históricas, políticas y culturales en que fueron escritos los poemas...

Mid-IR AGPMs for ELT applications

Carlomagno, Brunella; Delacroix, Christian; Absil, Olivier; Forsberg, Pontus; Habraken, Serge; Jolivet, Aїssa; Karlsson, Mikael; Mawet, Dimitri; Piron, Pierre; Surdej, Jean; Vargas Catalan, Ernesto
Fonte: Society of Photo-Optical Instrumentation Engineers (SPIE) Publicador: Society of Photo-Optical Instrumentation Engineers (SPIE)
Tipo: Book Section; PeerReviewed Formato: application/pdf
Publicado em 07/08/2014
Relevância na Pesquisa
16.54%
The mid-infrared region is well suited for exoplanet detection thanks to the reduced contrast between the planet and its host star with respect to the visible and near-infrared wavelength regimes. This contrast may be further improved with Vector Vortex Coronagraphs (VVCs), which allow us to cancel the starlight. One flavour of the VVC is the AGPM (Annular Groove Phase Mask), which adds the interesting properties of subwavelength gratings (achromaticity, robustness) to the already known properties of the VVC. In this paper, we present the optimized designs, as well as the expected performances of mid-IR AGPMs etched onto synthetic diamond substrates, which are considered for the E-ELT/METIS instrument.

Development of a subwavelength grating vortex coronagraph of topological charge 4 (SGVC4)

Delacroix, Christian; Absil, Olivier; Carlomagno, Brunella; Piron, Pierre; Forsberg, Pontus; Karlsson, Mikael; Mawet, Dimitri; Habraken, Serge; Surdej, Jean
Fonte: Society of Photo-Optical Instrumentation Engineers (SPIE) Publicador: Society of Photo-Optical Instrumentation Engineers (SPIE)
Tipo: Book Section; PeerReviewed Formato: application/pdf; application/pdf
Publicado em 06/08/2014
Relevância na Pesquisa
16.54%
One possible solution to achieve high contrast direct imaging at a small inner working angle (IWA) is to use a vector vortex coronagraph (VVC), which provides a continuous helical phase ramp in the focal plane of the telescope with a phase singularity in its center. Such an optical vortex is characterized by its topological charge, i.e., the number of times the phase accumulates 2π radians along a closed path surrounding the singularity. Over the past few years, we have been developing a charge-2 VVC induced by rotationally symmetric subwavelength gratings (SGVC2), also known as the Annular Groove Phase Mask (AGPM). Since 2013, several SGVC2s (or AGPMs) were manufactured using synthetic diamond substrate, then validated on dedicated optical benches, and installed on 10-m class telescopes. Increasing the topological charge seems however mandatory for cancelling the light of bright stars which will be partially resolved by future Extremely Large Telescopes in the near-infrared. In this paper, we first detail our motivations for developing an SGVC4 (charge 4) dedicated to the near-infrared domain. The challenge lies in the design of the pattern which is unrealistic in the theoretically perfect case, due to state-of-the-art manufacturing limitations. Hence...

Lyot-plane phase masks for improved high-contrast imaging with a vortex coronagraph

Ruane, G. J.; Huby, E.; Absil, O.; Mawet, D.; Delacroix, C.; Carlomagno, B.; Swartzlander, G. A.
Fonte: EDP Sciences Publicador: EDP Sciences
Tipo: Article; PeerReviewed Formato: application/pdf
Publicado em /11/2015
Relevância na Pesquisa
16.54%
Context. The vortex coronagraph is an optical instrument that precisely removes on-axis starlight allowing for high contrast imaging at small angular separation from the star, a crucial capability for direct detection and characterization of exoplanets and circumstellar disks. Telescopes with aperture obstructions, such as secondary mirrors and spider support structures, require advanced coronagraph designs to provide adequate starlight suppression. Aims. We introduce a phase-only Lyot-plane optic to the vortex coronagraph, which offers improved contrast performance on telescopes with complicated apertures. Potential solutions for the European Extremely Large Telescope (E-ELT) are described. Methods. Adding a Lyot-plane phase mask relocates residual starlight away from a region of the image plane, thereby reducing stellar noise and improving sensitivity to off-axis companions. The phase mask is calculated using an iterative phase retrieval algorithm. Results. Numerically, we achieve a contrast on the order of 10-6 for a companion with angular displacement as small as 4λ/D with an E-ELT type aperture. Even in the presence of aberrations, improved performance is expected compared to either a conventional vortex coronagraph or an optimized pupil plane phase element alone.

Realizing the diamond annular groove phase masks for the mid infrared region - five years of successful process development of diamond plasma etching

Forsberg, Pontus; Vargas, Ernesto; Delacroix, Christian; Absil, Olivier; Carlomagno, Brunella; Mawet, Dimitri; Habraken, Serge; Surdej, Jean; Karlsson, Mikael
Fonte: Society of Photo-Optical Instrumentation Engineers (SPIE) Publicador: Society of Photo-Optical Instrumentation Engineers (SPIE)
Tipo: Book Section; PeerReviewed Formato: application/pdf
Publicado em 07/08/2014
Relevância na Pesquisa
16.54%
The Annular Groove Phase Mask (AGPM) is a circularly symmetric half wave plate consisting of a circular high aspect ratio sub-wavelength grating. Here we present a method for realizing such structures in diamond. To improve the AGPM performance, antireflective sub-wavelength gratings are etched on the backside of the components, and such gratings are also discussed. Components for the N-band (around 10 μm) and the L-band (around 3.8 μm) have been successfully fabricated. We are currently developing the process further to improve the precision of the gratings and produce an AGPM for the K-band (around 2.2 μm).

The VORTEX project: first results and perspectives

Absil, Olivier; Mawet, Dimitri; Delacroix, Christian; Forsberg, Pontus; Karlsson, Mikael; Habraken, Serge; Surdej, Jean; Absil, Pierre-Antoine; Carlomagno, Brunella; Christiaens, Valentin; Defrère, Denis; Gomez Gonzales, Carlos; Huby, Elsa; Jolivet, Aїs
Fonte: Society of Photo-Optical Instrumentation Engineers (SPIE) Publicador: Society of Photo-Optical Instrumentation Engineers (SPIE)
Tipo: Book Section; PeerReviewed Formato: application/pdf; application/pdf
Publicado em 05/09/2014
Relevância na Pesquisa
16.54%
Vortex coronagraphs are among the most promising solutions to perform high contrast imaging at small angular separations from bright stars. They feature a very small inner working angle (down to the diffraction limit of the telescope), a clear 360 degree discovery space, have demonstrated very high contrast capabilities, are easy to implement on high-contrast imaging instruments, and have already been extensively tested on the sky. Since 2005, we have been designing, developing and testing an implementation of the charge-2 vector vortex phase mask based on concentric sub-wavelength gratings, referred to as the Annular Groove Phase Mask (AGPM). Science-grade mid-infrared AGPMs were produced in 2012 for the first time, using plasma etching on synthetic diamond substrates. They have been validated on a coronagraphic test bench, showing broadband peak rejection up to 500:1 in the L band, which translates into a raw contrast of about 6 x 10^(-5) at 2⋋=D. Three of them have now been installed on world-leading diffraction-limited infrared cameras, namely VLT/NACO, VLT/VISIR and LBT/LMIRCam. During the science verification observations with our L-band AGPM on NACO, we observed the beta Pictoris system and obtained unprecedented sensitivity limits to planetary companions down to the diffraction limit (0.1"). More recently...

Partidos, políticos e suas bases: elementos da articulação política local-federal na geografia eleitoral de 2014

Carlomagno, Márcio Cunha
Fonte: TRE/PR e UFPR Publicador: TRE/PR e UFPR
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Artigo Avaliado pelos Pares Formato: application/pdf
Publicado em 24/08/2015 POR
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Este artigo analisa os padrões de votação (mensurados pelo índice G de concen­tração de votos) obtidos por 5743 candidatos ao cargo de deputado federal em 26 estados brasileiros nas eleições de 2014. Seguindo a tese de que existe uma articu­lação política entre os níveis local e nacional, nosso objetivo é identificar se aspec­tos das bases políticas locais de que partidos dispõem (mensuradas por vereado­res, prefeitos e governador do mesmo partido), influenciam nas estratégias de como candidatos obtém seus votos. Para isso, combinamos dados das eleições 2014 e de 2012, a partir de quatro diferentes bancos fornecidos pelo TSE. No modelo de re­gressão geral, ter vereadores do partido é o elemento de ordem política que mais afeta a tendência à dispersão da votação por todo o estado – em oposição à sua concentração em um nicho específico. Contudo, olhando os detalhes das correla­ções, existem distinções importantes entre os partidos. Sobre os grandes partidos, o PT tende a ter os resultados mais dispersos e PMDB e PSDB os mais concen­trados. Os efeitos de cada tipo de base local também são diferentes a depender do partido, indicando que estes são afetados diferentemente por um mesmo fator.

EDITORIAL: POR UM ESPAÇO PARA A PLURALIDADE DE PESQUISAS PÓS-GRADUANDAS EM CIÊNCIA POLÍTICA

Carlomagno, Márcio Cunha; Universidade Federal do Paraná; Hartmann, José Augusto; Universidade Federal do Paraná
Fonte: UFPR Publicador: UFPR
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Formato: application/pdf
Publicado em 18/12/2013 POR
Relevância na Pesquisa
16.54%

EDITORIAL: NOVOS RUMOS E CONTINUIDADES NA PESQUISA E PUBLICAÇÃO EM CIÊNCIA POLÍTICA

Hartmann, José Augusto; Universidade Federal do Paraná; Carlomagno, Márcio Cunha; Universidade Federal do Paraná
Fonte: UFPR Publicador: UFPR
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Formato: application/pdf
Publicado em 18/12/2013 POR
Relevância na Pesquisa
16.54%

EXPEDIENTE

Carlomagno, Márcio Cunha; Universidade Federal do Paraná
Fonte: UFPR Publicador: UFPR
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Formato: application/pdf
Publicado em 18/12/2013 POR
Relevância na Pesquisa
16.54%

EXPEDIENTE

Carlomagno, Márcio Cunha; Universidade Federal do Paraná
Fonte: UFPR Publicador: UFPR
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Formato: application/pdf
Publicado em 29/07/2014 POR
Relevância na Pesquisa
16.54%

Expediente

Carlomagno, Márcio Cunha; Universidade Federal do Paraná
Fonte: UFPR Publicador: UFPR
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Formato: application/pdf
Publicado em 18/12/2013 POR
Relevância na Pesquisa
16.54%

Existe polarização nas postagens de Facebook de periódicos brasileiros durante as eleições?: Uma análise comparativa da disposição de informações sobre candidatos às eleições presidenciais no Brasil em 2014

Cervi, Emerson U.; Moreira, Adriana Cedillo Morales; Carlomagno, Márcio C.
Fonte: Revista Observatório Publicador: Revista Observatório
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; Formato: application/pdf
Publicado em 26/12/2015 POR
Relevância na Pesquisa
16.54%
O paper propõe uma análise comparativa das citações dos candidatos à presidência no Brasil a partir das fanfages de Facebook de 12 jornais brasileiros, com o objetivo de identificar, por região, o volume de cobertura e a existência de viés contrário ou favorável a determinado candidato. Utilizamos como metodologia predominante a análise quantitativa de conteúdo para analisar 34.618 posts publicados nas fan pages dos jornais, entre 1º de julho e 31 de outubro de 2014, que citavam pelo menos um dos três principais candidatos a presidente: Aécio Neves (PSDB), Dilma Rousseff (PT) ou Eduardo Campos/Marina Silva (PSB). A variável utilizada para testar a hipótese é a valência do post que cita os candidatos. Os testes demonstraram diferenças importantes entre o primeiro e o segundo turno nas posturas dos jornais por região. PALAVRAS-CHAVE: Facebook, Eleições 2014, Candidatos, Brasil   ABSTRACT This paper proposes a comparative analysis of presidential candidate's quotes from 12 Brazilian newspapers' fanpages, in order to identify, by region, the existence of bias against or in favor of a particular candidate. It was used predominantly a methodology of quantitative content analysis to study 34,618 newspapers' posts published...