Navegação Ciências Exatas e da Terra por Autor "Dottori, Horacio Alberto"
Resultados 1-20 de 63
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Ages and metallicities of lmc and smc red clusters through hb and g band photometry
(1986) [Artigo de periódico]We present narrow band integrated photometry of the Hβ and G band absorption features for 41 LMC and 10 SMC red star clusters. An age-metallicity calibration is provided for the color-color diagram. We derive SWB types ... -
Ages and metallicities of star clusters and surrounding fiels in the outer disk of the Large Magellanic Cloud
(1998) [Artigo de periódico]We present Washington system CT1 color-magnitude diagrams of 13 star clusters and their surrounding fields that lie in the outer parts of the LMC disk (r>4°), as well as a comparison inner cluster. The total area covered ... -
Analysis of resonances in grand design spiral galaxies
(2001) [Artigo de periódico]We have searched for corotation resonances (CRs) in three southern grand design spiral galaxies : NGC 1365, NGC 1566, and NGC 2997. We have also introduced a method of quantifying errors in the phase diagram used to detect ... -
Bar star cluster in the LMC : formation history from UBV integrated photometry
(1992) [Artigo de periódico]The sample of star clusters. in the LMC Bar region with integrated UBV photometry was enlarged by approximately a factor 4, totalling 129 objects. The (B- V) histogram gap between blue and red clusters disappears with this ... -
Blue-violet spectral evolution of young magellanic cloud clusters
(1995) [Artigo de periódico]We study the integrated spectral evolution in the blue-violet range of 97 blue star clusters in the Magellanic Clouds, from those associated with gas emission to those as old as a few hundred Myr. Some clusters are dominated ... -
Capture of field stars by globular clusters in dense bulge regions
(1997) [Artigo de periódico]The recent detection of a double red giant branch (RGB) in the optical color-magnitude diagram of the bulge globular cluster HP 1—a more populated, metal-poor, steep giant branch corresponding to the cluster itself and ... -
CCD imaging of NGC 4861 : ionized gas properties and stellar formation
(1994) [Artigo de periódico]This work undertakes the study of the galaxy NGC 4861, using imaging centered at the strong lines Hα, Hβ, [O III] λ5007 and nearby continua. Integrated, absolute fluxes of 28 H II regions, and the region known as the bright ... -
Ccd imaging of ngc 4861 : morphology and brightness distribution
(1994) [Artigo de periódico]We discuss narrow band CCD imaging of NGC 4861 in continua at 4500 Å, 5300 Å and 6300 Å as well as in Hα, Hβ and [OIII] λ 5007Å lines. We find that the system exhibits a double nucleus structure anda counter-tail to the ... -
Circumnuclear structures in the interacting Seyfert galaxy NGC 1241 : kinematics and optical/infrared morphology
(2003) [Artigo de periódico]We studied the spiral pattern in the inner 6".5 (1" = 257 pc) central regions of the interacting active nucleus galaxy NGC 1241 using Gemini North Telescope high-resolution Ks- and J-band images and Hubble Space Telescope ... -
Detection of ca II absorption triplet in a circumnuclear H II region of ngc 3310
(1990) [Artigo de periódico]We have obtained long slit spectrophotometry across NGC 3310, a lurninous galaxy with cucumnuclear bursts of star formation, covering the spectral range from λ3650 to 9700 Å. In one giant star-forrning region, the near-IR ... -
Determination of ochratoxin A in wine by high-performance thin-layer chromatography using charged coupled device
(2010) [Artigo de periódico]Um método foi desenvolvido e validado para a determinação de ocratoxina A (OTA) em vinho. Foi utilizado um sistema contendo um detector de carga acoplada (CCD) para adquirir as imagens fluorescentes da micotoxina obtidas ... -
Dissolving star cluster candidates
(2001) [Artigo de periódico]We present a list of 34 neglected entries from star cluster catalogues located at relatively high galactic latitudes (|b| > 15º) which appear to be candidate late stages of star cluster dynamical evolution. Although ... -
Dynamical studies of cluster pairs in the magellanic clouds
(1998) [Artigo de periódico]We performed N-body simulations of star cluster encounters with Hernquist’s TREECODE in a CRAY YMP-2E computer under different initial conditions (relative positions and velocities, cluster sizes, masses and concentration ... -
Extreme galactic wind and Wolf-Rayet features in infrared mergers and infrared quasi-stellar objects
(2003) [Artigo de periódico]We report, as a part of a long-term study of infrared (IR) mergers and IR quasi-stellar objects (QSOs), detailed spectroscopic evidence for outflow (OF) and Wolf–Rayet (WR) features in the nearby mergers NGC4038/39 and ... -
Final stages of N-body star cluster encounters
(2000) [Artigo de periódico]We performed numerical simulations of star cluster encounters with Hernquist's treecode on a CRAY YMP-2E computer. We used different initial conditions (relative positions and velocities, cluster sizes, masses and concentration ... -
Galaxy properties in different environments. II. Star formation in bulges of late-type spirals
(1994) [Artigo de periódico]The star formation history in the nucleus of late spiral galaxies is compared between a sample in a high galaxy density medium (HDS) and a control sample (CS) of isolated galaxies. We have observed 20 HDS and 18 CS galaxies ... -
Galaxy properties in different environments. I. The sample
(1994) [Artigo de periódico]This paper presents two galaxy samples, respectively in a high and in a low local density environments that were generated from the SSRS catalog using objective criteria. A preliminary comparison of physical properties in ... -
Genesis of a dwarf galaxy from the debris of the antennae
(1992) [Artigo de periódico]We show that a dwarf irregular galaxy has formed out of the tidal remnants that were ejected to intergalactic space during an encounter of the disk galaxies NGC 4038/39 (the Antennae). The tidal dwarf consists of a chain ... -
Hidden trigger for the giant starburst arc in M83?
(2006) [Artigo de periódico]The huge star formation events that occur at some galactic centers do not provide enough clues as to their origin, since the morphological signatures of the triggering mechanism are smeared out in the timescale of a few ... -
H II region age indicators
(1986) [Artigo de periódico]The evolution of some properties of H II regions such as the relative volume R of the He⁺ and H⁺ zones, the equivalent width Wнβ of the Hβ emission line and the ratio [O III]/Hβ of the lines [O II] λλ4959, 5007 to Hβ, was ...
