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C. Mendes de Oliveira

Bio: C. Mendes de Oliveira is an academic researcher from University of São Paulo. The author has contributed to research in topics: Galaxy & Galaxy group. The author has an hindex of 39, co-authored 179 publications receiving 5783 citations. Previous affiliations of C. Mendes de Oliveira include University of British Columbia & National Research Council.


Papers
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Journal ArticleDOI
TL;DR: In this article, the authors set constraints of the epochs of early-type galaxy formation through the "archaeology" of the stellar populations in local galaxies, using their models of absorption line indices that account for variable abundance ratios.
Abstract: The aim of this paper is to set constraints of the epochs of early-type galaxy formation through the 'archaeology' of the stellar populations in local galaxies. Using our models of absorption line indices that account for variable abundance ratios, we derive the stellar population parameters of 124 early-type galaxies in high and low density environments. We find that all three parameters age, metallicity, and alpha/Fe ratio are correlated with velocity dispersion. We further find evidence for an influence of the environment on the stellar population properties. Massive early-type galaxies in low-density environments appear on average ~2 Gyrs younger and slightly more metal-rich than their counterparts in high density environments. No offsets in the alpha/Fe ratios, instead, are detected. We translate the derived ages and alpha/Fe ratios into star formation histories. We show that most star formation activity in early-type galaxies is expected to have happened between redshifts 3 and 5 in high density and between redshifts 1 and 2 in low density environments. We conclude that at least 50 per cent of the total stellar mass density must have already formed at z 1, in good agreement with observational estimates of the total stellar mass density as a function of redshift. Our results suggest that significant mass growth in the early-type galaxy population below z 1 must be restricted to less massive objects, and a significant increase of the stellar mass density between redshifts 1 and 2 should be present caused mainly by the field galaxy population. The results of this paper further imply vigorous star formation episodes in massive objects at z 2-5 and the presence of evolved ellipticals around z 1, both observationally identified as SCUBA galaxies and EROs.

1,498 citations

Posted Content
TL;DR: The Javalambre-Physics of the Accelerated Universe Astrophysical Survey (J-PAS) as discussed by the authors is a very large-scale cosmological survey with a 2.5m telescope and a 4.7 sq.deg camera with 1.2Gpix.
Abstract: The Javalambre-Physics of the Accelerated Universe Astrophysical Survey (J-PAS) is a narrow band, very wide field Cosmological Survey to be carried out from the Javalambre Observatory in Spain with a purpose-built, dedicated 2.5m telescope and a 4.7 sq.deg. camera with 1.2Gpix. Starting in late 2015, J-PAS will observe 8500sq.deg. of Northern Sky and measure $0.003(1+z)$ photo-z for $9\times10^7$ LRG and ELG galaxies plus several million QSOs, sampling an effective volume of $\sim 14$ Gpc$^3$ up to $z=1.3$ and becoming the first radial BAO experiment to reach Stage IV. J-PAS will detect $7\times 10^5$ galaxy clusters and groups, setting constrains on Dark Energy which rival those obtained from its BAO measurements. Thanks to the superb characteristics of the site (seeing ~0.7 arcsec), J-PAS is expected to obtain a deep, sub-arcsec image of the Northern sky, which combined with its unique photo-z precision will produce one of the most powerful cosmological lensing surveys before the arrival of Euclid. J-PAS unprecedented spectral time domain information will enable a self-contained SN survey that, without the need for external spectroscopic follow-up, will detect, classify and measure $\sigma_z\sim 0.5\%$ redshifts for $\sim 4000$ SNeIa and $\sim 900$ core-collapse SNe. The key to the J-PAS potential is its innovative approach: a contiguous system of 54 filters with $145\AA$ width, placed $100\AA$ apart over a multi-degree FoV is a powerful "redshift machine", with the survey speed of a 4000 multiplexing low resolution spectrograph, but many times cheaper and much faster to build. The J-PAS camera is equivalent to a 4.7 sq.deg. "IFU" and it will produce a time-resolved, 3D image of the Northern Sky with a very wide range of Astrophysical applications in Galaxy Evolution, the nearby Universe and the study of resolved stellar populations.

219 citations

Journal ArticleDOI
TL;DR: In this paper, the authors report on the results of intensive ultraviolet spectral monitoring of the Seyfert 1 galaxy NGC 3783, which was observed with the International Ultraviolet Explorer satellite on a regular basis for a total of 7 months, once every 4 days for the first 172 days and once every other day for the final 50 days.
Abstract: We report on the results of intensive ultraviolet spectral monitoring of the Seyfert 1 galaxy NGC 3783. The nucleus of NGC 3783 was observed with the International Ultraviolet Explorer satellite on a regular basis for a total of 7 months, once every 4 days for the first 172 days and once every other day for the final 50 days. Significant variability was observed in both continuum and emission-line fluxes. The light curves for the continuum fluxes exhibited two well-defined local minima or 'dips,' the first lasting is less than or approximately 20 days and the second is less than or approximately 4 days, with additional episodes of relatively rapid flickering of approximately the same amplitude. As in the case of NGC 5548 (the only other Seyfert galaxy that has been the subject of such an intensive, sustained monitoring effort), the largest continuum variations were seen at the shortest wavelengths, so that the continuum became 'harder' when brighter. The variations in the continuum occurred simultaneously at all wavelengths (delta(t) is less than 2 days). Generally, the amplitude of variability of the emission lines was lower than (or comparable to) that of the continuum. Apart from Mg II (which varied little) and N V (which is relatively weak and badly blended with Ly(alpha), the light curves of the emission lines are very similar to the continuum light curves, in each case with a small systematic delay or 'lag.' As for NGC 5548, the highest ionization lines seem to respond with shorter lags than the lower ionization lines. The lags found for NGC 3783 are considerably shorter than those obtained for NGC 5548, with values of (formally) approximately 0 days for He II + O III), and approximately 4 days for Ly(alpha) and C IV. The data further suggest lags of approximately 4 days for Si IV + O IV) and 8-30 days for Si III + C III). Mg II lagged the 1460 A continuum by approximately 9 days, although this result depends on the method of measuring the line flux and may in fact be due to variability of the underlying Fe II lines. Correlation analysis further shows that the power density spectrum contains substantial unresolved power over timescales of is less than or approximately 2 days, and that the character of the continuum variability may change with time.

155 citations

Journal ArticleDOI
TL;DR: In this paper, the properties of the early-type dwarf galaxy population (MV > −17 mag) in the Hydra I cluster were analyzed using the galaxy luminosity function (LF), the colour-magnitude relation (CMR), and the magnitude-surface brightness relation down to MV ∼− 10 mag.
Abstract: Aims. We analyse the properties of the early-type dwarf galaxy population (MV > −17 mag) in the Hydra I cluster. We investigate the galaxy luminosity function (LF), the colour-magnitude relation (CMR), and the magnitude-surface brightness relation down to MV ∼− 10 mag. Another goal of this study is to find candidates for ultra-compact dwarf galaxies (UCDs) in Hydra I. Methods. Two spectroscopic surveys performed with Magellan I/LDSS2 at Las Campanas Observatory and VLT/VIMOS, as well as deep VLT/FORS1 images in V and I bands, covering the central parts of the cluster, were examined. We identify cluster members by radial velocity measurements and select other cluster galaxy candidates by their morphology and low surface brightness. The candidates’ total magnitudes and central surface brightnesses were derived from the analysis of their surface brightness profiles. To determine the faint-end slope of the LF, the galaxy number counts are completeness corrected. Results. We obtain radial velocities for 126 objects and identify 32 cluster members, of which 5 are previously uncatalogued dwarf galaxies. One possible UCD candidate with MV = −13.26 mag is found. Our sample of � 100 morphologically selected dwarf galaxies with MV > −17 mag defines a CMR that extends the CMR of the giant cluster galaxies to the magnitude limit of our survey (MV ∼ −10 mag). It matches the relations found for the Local Group (LG) and the Fornax cluster dwarf galaxies almost perfectly. The Hydra I dwarf galaxies also follow a magnitude-surface brightness relation that is very similar to that of the LG dwarf galaxies. Moreover, we observe a continuous relation for dwarf galaxies and giant early-type galaxies when plotting the central surface brightness μ0 of a Sersic model vs. the galaxy magnitude. The effective radius is found to be largely independent of the luminosity for MV > −18 mag. It is consistent with a constant value of Re ∼ 0.8 kpc. We present the photometric parameters of the galaxies as the Hydra I Cluster Catalogue (HCC). By fitting a Schechter function to the luminosity distribution, we derive a very flat faint-end slope of the LF (α = −1.13 ± 0.04), whereas fitting a power law for MV > −14 mag gives α = −1.40 ± 0.18. Conclusions. Our findings of a continuous CMR and μ0 − MV relation for dwarf and giant early-type galaxies suggests that they are the same class of objects. The similarity of those relations to other environments like the LG implies that internal processes could be more important for their global photometric properties than external influences.

128 citations

Journal ArticleDOI
A. J. Cenarro1, Mariano Moles, David Cristóbal-Hornillos1, Antonio Marín-Franch1, Alessandro Ederoclite1, Jesús A. Varela1, Carlos López-Sanjuan1, C. Hernández-Monteagudo1, Raul E. Angulo, H. Vázquez Ramió, Kerttu Viironen1, S. Bonoli1, Alvaro Orsi, G. Hurier, I. San Roman, N. Greisel, G. Vilella-Rojo, L. A. Díaz-García, R. Logroño-García, Siddhartha Gurung-López, D. Spinoso, David Izquierdo-Villalba, J. A. L. Aguerri1, J. A. L. Aguerri2, C. Allende Prieto2, C. Allende Prieto1, C. Bonatto3, J. M. Carvano, Ana L. Chies-Santos3, Simone Daflon, R. A. Dupke4, R. A. Dupke5, Jesús Falcón-Barroso1, Jesús Falcón-Barroso2, Denise R. Gonçalves6, Y. Jimenez-Teja, Alberto Molino7, Vinicius M. Placco8, Enrique Solano1, Devin D. Whitten8, J. Abril, Jordi Anton, R. Bello, S. Bielsa de Toledo, J. Castillo-Ramirez, Sergio Chueca, T. Civera, M. C. Díaz-Martín, M. Dominguez-Martinez, J. Garzaran-Calderaro, J. Hernández-Fuertes, R. Iglesias-Marzoa, C. Íniguez, J. M. Jimenez Ruiz, K. Kruuse, J. L. Lamadrid, N. M. Lasso-Cabrera, G. López-Alegre, A. López-Sainz, N. Maicas, A. Moreno-Signes, D. Muniesa, S. Rodríguez-Llano, F. Rueda-Teruel, S. Rueda-Teruel, I. Soriano-Laguia, V. Tilve, L. Valdivielso, A. Yanes-Díaz, Jailson S. Alcaniz9, C. Mendes de Oliveira7, Laerte Sodré7, Paula Coelho7, R. Lopes de Oliveira, Antti Tamm10, H. S. Xavier7, Luis Raul Weber Abramo7, Stavros Akras, Emilio J. Alfaro1, Alvaro Alvarez-Candal, B. Ascaso, Michael A. Beasley1, Michael A. Beasley2, Timothy C. Beers8, M. Borges Fernandes, G. R. Bruzual11, M. L. Buzzo7, J. M. Carrasco12, J. Cepa1, J. Cepa2, Arianna Cortesi7, M. V. Costa-Duarte7, M. De Prá, Ginevra Favole, A. Galarza, Lluís Galbany13, K. Garcia6, R. M. González Delgado1, José Ignacio González-Serrano1, L. A. Gutiérrez-Soto6, J. A. Hernandez-Jimenez7, Antonio Kanaan, Hanindyo Kuncarayakti14, Ricardo G. Landim7, J. Laur10, Javier Licandro2, Javier Licandro1, G. B. Lima Neto7, J. D. Lyman15, J. Maíz Apellániz1, Jordi Miralda-Escudé16, Jordi Miralda-Escudé12, D. Morate1, J. P. Nogueira-Cavalcante, P. M. Novais7, M. Oncins12, Ivan Oteo17, Ivan Oteo18, Roderik Overzier, C. B. Pereira, Alberto Rebassa-Mansergas19, Ribamar R. R. Reis6, Fernando Roig, M. Sako20, N. Salvador-Rusinol2, N. Salvador-Rusinol1, L. Sampedro7, Patricia Sanchez-Blazquez21, W. A. Santos7, Linda Schmidtobreick17, Beatriz B. Siffert6, Eduardo Telles, José M. Vílchez1 
TL;DR: The Javalambre Photometric Local Universe Survey (J-PLUS) as mentioned in this paper is an ongoing 12-band photometric optical survey, observing thousands of square degrees of the Northern Hemisphere from the dedicated JAST/T80 telescope at the OAS.
Abstract: The Javalambre Photometric Local Universe Survey (J-PLUS) is an ongoing 12-band photometric optical survey, observing thousands of square degrees of the Northern Hemisphere from the dedicated JAST/T80 telescope at the Observatorio Astrofisico de Javalambre (OAJ). The T80Cam is a camera with a field of view of 2 deg 2 mounted on a telescope with a diameter of 83 cm, and is equipped with a unique system of filters spanning the entire optical range (3500-10 000 A). This filter system is a combination of broad-, medium-, and narrow-band filters, optimally designed to extract the rest-frame spectral features (the 3700-4000 A Balmer break region, Hδ, Ca H+K, the G band, and the Mg b and Ca triplets) that are key to characterizing stellar types and delivering a low-resolution photospectrum for each pixel of the observed sky. With a typical depth of AB ∼21.25 mag per band, this filter set thus allows for an unbiased and accurate characterization of the stellar population in our Galaxy, it provides an unprecedented 2D photospectral information for all resolved galaxies in the local Universe, as well as accurate photo-z estimates (at the δ z/(1 + z)∼0.005-0.03 precision level) for moderately bright (up to r∼20 mag) extragalactic sources. While some narrow-band filters are designed for the study of particular emission features ([O II]/λ3727, Hα/λ6563) up to z< 0.017, they also provide well-defined windows for the analysis of other emission lines at higher redshifts. As a result, J-PLUS has the potential to contribute to a wide range of fields in Astrophysics, both in the nearby Universe (Milky Way structure, globular clusters, 2D IFU-like studies, stellar populations of nearby and moderate-redshift galaxies, clusters of galaxies) and at high redshifts (emission-line galaxies at z≈0.77, 2.2, and 4.4, quasi-stellar objects, etc.). With this paper, we release the first ∼1000 deg 2 of J-PLUS data, containing about 4.3 million stars and 3.0 million galaxies at r< 21 mag. With a goal of 8500 deg 2 for the total J-PLUS footprint, these numbers are expected to rise to about 35 million stars and 24 million galaxies by the end of the survey.

118 citations


Cited by
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01 Jan 2016
TL;DR: The modern applied statistics with s is universally compatible with any devices to read, and is available in the digital library an online access to it is set as public so you can download it instantly.
Abstract: Thank you very much for downloading modern applied statistics with s. As you may know, people have search hundreds times for their favorite readings like this modern applied statistics with s, but end up in harmful downloads. Rather than reading a good book with a cup of coffee in the afternoon, instead they cope with some harmful virus inside their laptop. modern applied statistics with s is available in our digital library an online access to it is set as public so you can download it instantly. Our digital library saves in multiple countries, allowing you to get the most less latency time to download any of our books like this one. Kindly say, the modern applied statistics with s is universally compatible with any devices to read.

5,249 citations

Journal Article
TL;DR: The first direct detection of gravitational waves and the first observation of a binary black hole merger were reported in this paper, with a false alarm rate estimated to be less than 1 event per 203,000 years, equivalent to a significance greater than 5.1σ.
Abstract: On September 14, 2015 at 09:50:45 UTC the two detectors of the Laser Interferometer Gravitational-Wave Observatory simultaneously observed a transient gravitational-wave signal. The signal sweeps upwards in frequency from 35 to 250 Hz with a peak gravitational-wave strain of 1.0×10(-21). It matches the waveform predicted by general relativity for the inspiral and merger of a pair of black holes and the ringdown of the resulting single black hole. The signal was observed with a matched-filter signal-to-noise ratio of 24 and a false alarm rate estimated to be less than 1 event per 203,000 years, equivalent to a significance greater than 5.1σ. The source lies at a luminosity distance of 410(-180)(+160) Mpc corresponding to a redshift z=0.09(-0.04)(+0.03). In the source frame, the initial black hole masses are 36(-4)(+5)M⊙ and 29(-4)(+4)M⊙, and the final black hole mass is 62(-4)(+4)M⊙, with 3.0(-0.5)(+0.5)M⊙c(2) radiated in gravitational waves. All uncertainties define 90% credible intervals. These observations demonstrate the existence of binary stellar-mass black hole systems. This is the first direct detection of gravitational waves and the first observation of a binary black hole merger.

4,375 citations

Journal ArticleDOI
TL;DR: In this article, the authors present a comprehensive study of the physical properties of ∼ 10 5 galaxies with measurable star formation in the Sloan Digital Sky Survey (SDSS) by comparing physical information extracted from the emission lines with continuum properties, and build up a picture of the nature of star-forming galaxies at z < 0.2.
Abstract: We present a comprehensive study of the physical properties of ∼ 10 5 galaxies with measurable star formation in the Sloan Digital Sky Survey (SDSS). By comparing physical information extracted from the emission lines with continuum properties, we build up a picture of the nature of star-forming galaxies at z < 0.2. We develop a method for aperture correction using resolved imaging and show that our method takes out essentially all aperture bias in the star formation rate (SFR) estimates, allowing an accurate estimate of the total SFRs in galaxies. We determine the SFR density to be 1.915 +0.02 −0.01 (random) +0.14

3,262 citations

Journal ArticleDOI
TL;DR: In this paper, supermassive black holes (BHs) have been found in 85 galaxies by dynamical modeling of spatially resolved kinematics, and it has been shown that BHs and bulges coevolve by regulating each other's growth.
Abstract: Supermassive black holes (BHs) have been found in 85 galaxies by dynamical modeling of spatially resolved kinematics. The Hubble Space Telescope revolutionized BH research by advancing the subject from its proof-of-concept phase into quantitative studies of BH demographics. Most influential was the discovery of a tight correlation between BH mass and the velocity dispersion σ of the bulge component of the host galaxy. Together with similar correlations with bulge luminosity and mass, this led to the widespread belief that BHs and bulges coevolve by regulating each other's growth. Conclusions based on one set of correlations from in brightest cluster ellipticals to in the smallest galaxies dominated BH work for more than a decade. New results are now replacing this simple story with a richer and more plausible picture in which BHs correlate differently with different galaxy components. A reasonable aim is to use this progress to refine our understanding of BH-galaxy coevolution. BHs with masses of 105−106M...

2,804 citations

01 Jan 2005
TL;DR: The Monthly Notices as mentioned in this paper is one of the three largest general primary astronomical research publications in the world, published by the Royal Astronomical Society (RAE), and it is the most widely cited journal in astronomy.
Abstract: Monthly Notices is one of the three largest general primary astronomical research publications. It is an international journal, published by the Royal Astronomical Society. This article 1 describes its publication policy and practice.

2,091 citations