Navegação Ciências Exatas e da Terra por Autor "Schmidt, Alex Andre"
Resultados 1-9 de 9
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Ages and metallicities of circumnuclear star formation regions from Gemini IFU observations
Dors Júnior, Oli Luiz; Storchi-Bergmann, Thaisa; Riffel, Rogemar André; Schmidt, Alex Andre (2008) [Artigo de periódico]Aims. We derive the age and metallicity of circumnuclear star formation regions (CNSFRs) located in the spiral galaxies NGC6951 and NGC1097 and investigate the cause of the very low equivalent widths of emission lines found ... -
BS 196 : an old star cluster far from the Small Magellanic Cloud main body
Bica, Eduardo Luiz Damiani; Santos Junior, Joao Francisco Coelho dos; Schmidt, Alex Andre (2008) [Artigo de periódico]We present B and V photometry of the outlying Small Magellanic Cloud (SMC) star cluster BS 196 with the 4.1-m SOAR telescope. The photometry is deep (to V≈25), showing ≈ 3 mag below the cluster turnoff point at MV = 2.5 ... -
Disentangling age and metallicity effects in the blueish nuclear population of m 33, ngc 278 and ngc 404
Schmidt, Alex Andre; Bica, Eduardo Luiz Damiani; Alloin, Danielle Marie (1990) [Artigo de periódico]In this study, we have applied to the blueish nuclei of the spiral galaxies M33 and NGC 278 and to the dwarf lenticular NGC 404, a population synthesis method relying upon a base of star clusters, over the range 3700-9700 ... -
On the meaning of a minimization procedure applied to a degenerate astrophysical problem
Schmidt, Alex Andre; Bica, Eduardo Luiz Damiani; Dottori, Horacio Alberto (1989) [Artigo de periódico]We apply the MINOS optimization system to the population synthesis of galaxy nuclei using as basis a grid of star cluster spectral features as a function of age and metallicity. In inverse numerical problems, a minimization ... -
Simulations of starburst spectral evolution superimposed on old populations : extension to dwarf ellipticals
Schmidt, Alex Andre; Alloin, Danielle Marie; Bica, Eduardo Luiz Damiani (1995) [Artigo de periódico]In order to gain a better understanding of starburst and merger events, we have extended to dwarf galaxies our previous spectral simulations of burst evolution over 3 Gyr, superimposed on an old underlying stellar population. ... -
Spin-glass freezing in Kondo-lattice compounds
Theumann, Alba Graciela Rivas de; Coqblin, Bernard; Magalhaes, Sergio Garcia; Schmidt, Alex Andre (2001) [Artigo de periódico]A theory is presented that describes a spin-glass phase at finite temperatures in Kondo-lattice systems with an additional Ruderman–Kittel–Kasuya–Yosida interaction represented by long range, random couplings among localized ... -
Star formation history and chemical enrichment in the nuclear regions of m31 and its dwarf companions m32 and ngc 205
Bica, Eduardo Luiz Damiani; Alloin, Danielle Marie; Schmidt, Alex Andre (1990) [Artigo de periódico]We present a comparative discussion about the stellar population and chemical enrichment in the nuclear regions of M 31 and of its dwarf companions M 32 and NGC 205, from a new set of long slit CCD spectra in the range ... -
Starsbursts superimposed on old populations : spectral evolution of the composite system over 3x10 9 yr
Bica, Eduardo Luiz Damiani; Alloin, Danielle Marie; Schmidt, Alex Andre (1990) [Artigo de periódico]We simulate in this paper the occurrence of star formation events superimposed on old populations, during the last 3 x 109 yr, by combining star cluster integrated spectra of different ages with those of red strong-lined ... -
Structures in surface-brightness profiles of LMC and SMC star clusters : evidence of mergers?
Carvalho, Luziane Oliveira; Saurin, Tiago Abreu; Bica, Eduardo Luiz Damiani; Bonatto, Charles Jose; Schmidt, Alex Andre (2008) [Artigo de periódico]Context. The LMC and SMC are rich in binary star clusters, and some mergers are expected. It is thus important to characterise single clusters, binary clusters and candidates for mergers. Aims. We selected a sample of star ...